COLUMBrA LIBRARIES OFFSITE HEALTH SCIENCES STANDARD F HX64074676 RA644.T8 W57 1 908 Typhoid fever; its c RECAP Kj-U'^ .GE C.WHIPPLift mSmmBmm B. LOGIN & SON, Medical Book Dealers & Binders 1328 THIRD AVENUE, IN EW YORK. College of ^fjpsicianjf anb ^urgeoni 3^ef erente l^ibrarp I TYPHOID FEVER ITS CAUSATION, TRANSMISSION AND PREVENTION WORKS OF G. C. WHIPPLE PUBLISHED BY JOHN WILEY & SONS. The Microscopy of Drinking=water. Second edition, revised. 8vo, xii + 338 pages, figures in the text and ig full-page half-tones. Cloth, $3.50. The Value of Pure Water, Large i2mo, viii+ 84 pages. Cloth, $1.00. Typhoid Fever — Its Causation, Transmission and Prevention. Introduction by William T. Sedgwick, Ph.D. Large i2ino, xxxvi -1- 407 pages, 50 figures. Cloth, ^3.00 net. Digitized by the Internet Arciiive in 2010 witii funding from Open Knowledge Commons http://www.archive.org/details/typhoidfeveritscOOwhip o > LU X h- o I- z o w CO CO z < DC H DC LU > LU O I Q. >- I- z: UJ < Q_ X I- o 01 z o H O UJ I- o DC a. o CO z < UJ TYPHOID FEVER ITS CAUSATION, TRANSMISSION AND PREVENTION BY GEORGE C. WHIPPLE CONSULTING ENGINEER WITH AN INTRODUCTORY ESSAY BY WILLIAM T. SEDGWICK PROFESSOR OF BIOLOGY, MASSACHUSETTS INSTITUTE OF TECHNOLOGY FIRST EDITION FIRST THOUSAND NEW YORK JOHN WILEY & SONS London: CHAPMAN & HALL, Limited 1908 Copyright, 1908, DY GEORGE C. WHIPPLE Stanbope ipresa F. H. GILSON COMPANY BOSTON. U.S.A. To THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY My Alma Mater A Piont;er in Sanitary Education ENTITLED TO THE GRATITUDE OF EVERY ONE WHO VALUES THE PUBLIC HEALTH K PREFACE. Few people, according to vital statistics, die of old age; almost every one dies of disease; and when your turn and mine shall come to shuffle off this mortal coil, we shall have the unwelcome and involuntary lot of more than two hundred different diseases. The human body is a machine. Occasionally it is put together wrong; the various parts do not work in harmony. More often the machine is improperly operated; it is driven too fast, or it is given too much fuel, or not enough. Derangements due to these internal causes are termed "constitutional" and "local" diseases. There is another group of diseases which attack the body from without. They are the infectious diseases, or contagious diseases, parasitic diseases, zymotic diseases, as they are variously called. Alike in the fact that they are all caused by living organisms, they differ in many ways. The organisms themselves are different. Each has an individuality of its own, which the bacteriologist has come to recognize and to understand. There are differences in biological character, in habitat, in mode of development, in means of trans- mission, in the manner of attacking the body, in viru- lence, in longevity, in powers of resistance against remedial measures. ix X PREFACE. But the human body is more than a machine; it is an organism of living cells, each a living entity, and each working for the good of all. Invaded by cells from with- out, a mortal struggle takes place within the body. The enemy, though microscopic in size, and fighting with the aid of insidious toxins, has often been the victor; but, thanks to the science of bacteriology and its influences in the arts of healing and of public sanitation, the terrible ravages of the infectious diseases known in former days have been checked, and all along the line there has been marked progress in combating the bac- terial foes. How great the value of the modern sanitary arts is to the welfare of the human race is seldom realized, yet the vital statistics published year after year are filled with proofs that diseases are gradually lessening and that the span of human life is lengthening. Among the infectious diseases few are more dreaded by the general public than typhoid fever. Although less common and less dangerous than many diseases, yet because of its insidious invasion, its prolonged run of fever and prostration, its frequent epidemic character, and its too frequent fatal ending, typhoid fever has come to occupy almost the first place in popular thought among the diseases of mankind. People have come to recognize, too, that it is one of the preventable diseases, and that whenever a case of typhoid fever occurs some- body has been at fault somewhere. All this has naturally given rise to many misconceptions, — not only among the laity, but, unfortunately, among members of the medical profession. Many true theories have been over- worked, many accurate bits of bacteriological evidence PREFACE. XI have been unduly exaggerated, unproven statements have been given currency, while some of the less tech- nical but more practical matters have been undervalued or almost entirely overlooked. As an illustration of this situation we may take the current opinion of the nature of the disease, — its infectious character has been so much emphasized that the fact that it is contagious as well as infectious has been quite neglected. The fight against typhoid fever must be made largely by men of two professions, by physicians and engineers. Differences in temperament, in training, and in the nature of their work have prevented these two profes- sions from cooperating as closely as they must if typhoid fever is to be relegated to the class of infrequent diseases. The doctor naturally thinks of men as individuals; he is not accustomed to think of men in masses. The sanitary engineer, with his genius for mathematics and statistics, studies communities at large, and is in danger of neglect- ing to study the details of particular cases. The two professions admirably supplement each other. The engineer is by training the best fitted to control the measures which are instrumental in warding off the disease, to deal with matters of water-supply, sewage disposal, and the other sanitary arts; while the physician is best fitted to attack the disease in the household. The object of this book is to furnish to the members of these two professions a condensed summary of the most important facts that have been learned regarding typhoid fever, so far as they relate to the prevention and spread of the disease; to furnish to the student of sani- tary science a group of illustrations of some of the leading xii PREFACE. principles of epidemiology; and to give to the general reader a simple and, it is hoped, a clear and correct account of the causation, transmission and prevention of the disease, and his own responsibility in helping to bring about such conditions of cleanliness that typhoid fever shall soon cease to be a national disgrace. New York, April., 1908. ACKNOWLEDGMENTS. The author, being more familiar with the engineering side of his subject than its other phases, has been compelled to invoke the aid of his many friends in the medical profession in the preparation of this book. To all of them he wishes to express his thanks, and in particular to Dr. Herbert D. Pease, Director of the State Hygienic Laboratory of the New York State Department of Health ; Dr. E. C. Levy, Chief Health Officer, Richmond, Va. ; Mr. Francis F. Longley, Chief Chemist and Assistant Superintendent of the Washington Aqueduct Filtra- tion Plant ; and to his own family physician, Dr. A. Ross Matheson, of Brooklyn, N.Y. He is also under obligations to many others, who, because they are many, must here be nameless, — to authors of various memoirs from which quotations have been freely made, some- times, perhaps, with too scant acknowledgment; to health officers in many cities both in this country and abroad, who have contributed typhoid statistics; and to his nearer pro- fessional friends and associates who have given advice and assistance in many ways. And, finally, to Prof. WiUiam T. Sedgwick, of the Massa- chusetts Institute of Technology, from whom the author received his first lessons and acquired his first interest in the science of epidemiology. zui CONTENTS. CHAPTER I. TYPHOID FEVER. PAGE Typhoid Fever. — Symptoms. — Tj'pical Case. — Treatment. — Complications. — "Walking" Cases. — Allied Diseases i CHAPTER II. BACTERIOLOGY OF TYPHOID FEVER. The Typhoid Bacillus. — Specific Cause of the Disease. — Portals of EntT}'. — • Multiplication in the Body. — Typho-toxin. — Natural Defenses of the Body. — Widal Test. — Blood Tests. — Modes of Exit. — Typhoid Carriers 8 CHAPTER III. THE TYPHOID PATIENT AS A FOCUS OF INFECTION. The Endless Chain. — Barriers Against the Spread of the Disease. — Vehicles of Infection. — Contagion. — Duty of the Physician. — Duty of the Nurse. — Disinfection. — Report to Board of Health. — Duty of the Household. — Disinfectants. — Dis- posal of Fecal Matter. — Cleanliness. — Isolation. — Children. — Dut^' of Public Authorities. — System of Reporting Cases. — Blood Tests. — Supervision over Disinfection. — Sewage Dis- posal. — Disposal of Fecal Matter on Boats and Trains. — Care of Toilet Rooms. — Flies 21 xvi CONTENTS. CHAPTER IV. THE TYPHOID BACILLUS AT LARGEo PAGE The Typhoid Bacillus Outside the Body. — Requirements for Growth. — Moisture. — Sunlight. — Temperature. — Food. — Longevity in Water. — Decrease of Bacilli in Water. — The Resistant Minority. — Longevity in Sewage. — Decrease of Bacilli in Sewage. — Fate of Bacilli in Cesspools. — Efficiency of Sewage Purification. — Self Purification of Streams. — Effect of Dilution. — Sedimentation. — Time. — Aeration and Oxida- tion. — Present Status of Theory of Self Purification of Streams. — Self Purification of Lakes and Reservoirs. — Dispersion. — Sedimentation. — Beneficial Influence of Storage. — Antagon- ism of Microscopic Organisms. — Dangers of Depending upon Storage Alone. — Self Purification in Conduits and Pipes. — Dead Ends. — Longevity in Ice. — Natural Ice. — Artificial Ice. — Handling of Ice. — Longevity in the Soil. — Longevity in Milk. — Longevity in Oysters. — Longevity in Flies. — Longevity on Fabrics 41 CHAPTER V. LINES OF DEFENSE AGAINST THE TYPHOID BACILLUS Co-operative Work Necessary. — Public Responsibility. — Value of Statistics. — Public Water Supplies. — Filtration Increasing. — Standards of Purity Rising. — Safety of Ground Waters. — Dangers from Surface Waters. — Sanitary Supervision of Water- sheds. — Effect of Filtration. — Vended Waters. — Dangers from Dirty Milk. — Certified Milk. — Pasteurized Milk. — Regulation of Oyster Culture. — Supervision of Food Supplies. — Educational Work. — Household Responsibility. — • The Country Well. — Boiling the Water. — House Filters. — Pas- teurization of Milk. — Screening the Windows. — Personal Responsibility. — The Health Tone. — Risks of Traveling. — Nostrums 69 CHAPTER VI. TYPHOID FEVER STATISTICS. Nature of Statistics. — Death Rates. — Sources of Error. — Morbidity Statistics. — ■ Sources of Information 92 CONTENTS. xvii CHAPTER VII. DISTRIBUTION OF TYPHOID FEVER. PAGE Age. — Sex. — Racial. — Occupation. — Rural and Urban. — Climatic. — Geographical. — Geological. — Hydrographic. — Seasonal. — Vacation Typhoid. — Chronological. — Spanish War. — Causes 103 CHAPTER VIII. TYPHOID FEVER EPIDEMICS. Classification of Epidemics. — Plymouth. — New Haven. — Ithaca. — Scranton. — Lowell and Lawrence. — Waterville and Augusta. — Pittsburg and Allegheny. — Chicago. — Cleveland. — Burlington. — Butler. — Lowell, 1902. — Milli- nocket. — Baraboo. — Great Lakes Steamer. — Lausen. — Basingstoke. — Newport. — Auxerre. — Trenton. — Mount Savage. — New Haven Jail. — Winnipeg. — Military Camps. — Japanese- Russian War. — Somerville. — Springfield. — Stam- ford. — Marlborough. — Waterbury. — Montclair. — Wesleyan. — Winchester. — Southampton. — Lawrence. — Springfield, 1 905 , — Ogdensburg. — Special Characteristics. — Warnings. — In- fection Widespread. — Epidemics as Life Savers 134 CHAPTER IX. INVESTIGATION AND CONTROL OF TYPHOID FEVER EPIDEMICS. Collection of Data. — Study of Data. — Control of Epidemics . 216 CHAPTER X. INFLUENCE OF PUBLIC WATER SUPPLIES ON THE TYPHOID FEVER DEATH RATES OF CITIES. Frankfort-on-the-Main. — Newark. — Jersey City. — Cleveland. — Lowell. — Zurich. — Hamburg. — Lawrence. — Albany. — Binghamton. — Watertown. — Paterson. — Paris. — St. Louis. — Philadelphia. — Benefits of Filtration. — Youngstown. — Washington. — Boston. — New York. — Brooklyn. — Balti- more. — Lorain. — Stream Pollution 228 xviii CONTENTS. CHAPTER XI. EFFECT OF MILK SUPPLIES ON THE TYPHOID FEVER DEATH RATES OF CITIES. PAGE Glasgbw. — Liverpool. — Washington. — ■ German Cities . . . . 267 CHAPTER XII. THE FmANCLA.L ASPECT. Financial Value of Life. — Cost of Typhoid Fever to txie Country. — Effect of Filtration. — Effect of Contamination. — Con- clusion 273 APPENDICES. Appendix I. Appendix II. Appendix III. Appendix I^'. Appendix A'. Appendix \1. Appendix \11. Appendix \111. Appendix IX. Appendix X. Appendix XI. Appendix XII. Appendix : xin. Appendix XIV. Appendix XV. Appendix '. X\1. FACE The Use of Disinfectants 287 House Flies. From paper of Dr. L. O. Howard . 296 The Estimation of Population 303 Corrected Death-rates 307 Bacteriological Description of B. tj'phi 314 Tests for Diagnosis of Typhoid Fever. (Circular of Information of Department of Health, Cit}' of New York.) 317 Bacteriology of the Blood. By Dr. Warren Coleman and Dr. B. H. Buxton 322 Examination of Water for B. t}'phi 332 Water Analysis and Investigations of T}^hoid Epidemics. By Dr. E. C. Le^y 337 ViabiUty of the T}-phoid Bacillus Under Natural Conditions. By Dr. H. D. Pease 344 Typhoid Fever in United States Army Camps . . 356 Extract from President Roosevelt's Message . . 361 }vledicine in Peace and War. By Dr. L. L. Seaman 362 Economic Statistics, Pittsburg, Pa 367 T}'phoid Fever Literature. 368 Tables of Typhoid Fever Statistics 372 LIST OF ILLUSTRATIONS. PAGE Frontispiece. Diagram Illustrating Transmission of Typhoid Fever iv Fig. I. Diagram Showing Temperature of the Body in Typhoid Fever 4 Fig. 2. The Typhoid Bacillus 9 Fig. 3. Diagram Illustrating Longevity of the Typhoid Bacillus in Water 48 Fig. 4. Diagram Showing Typhoid Fever in St. Louis loi Fig. 5. Diagram Showing Age Distribution of Typhoid Fever . . 107 Fig. 6. Map of United States Showing Distribution of Typhoid Fever 114 Fig. 7. Diagram Illustrating Seasonal Distribution of Typhoid Fever 121 Fig. 8, Diagram Illustrating Seasonal Distribution of Typhoid Fever in Cities .' 122 Fig. 9. Diagram Illustrating Seasonal Distribution of Typhoid Fever in Albany, N. Y 123 Fig. ID. Diagram Showing Relation Between Atmospheric Tem- perature and Typhoid Fever 124 Fig. II. Diagram Showing Decrease in Typhoid Fever since 1880, 130 Fig. 12. Diagram Showing Typhoid Fever Epidemic in Gelsen- kichen, Germany 148 Fig. 13. Diagram Showing Typhoid Fever in Lowell and Law- rence, Mass 153 Fig. 14. Diagram Showing Typhoid Fever in Waterville and Augusta, Me 156 Fig. 15. Diagram Showing Typhoid Fever in Pittsburg, Pa. ... 160 Fig. 16. Diagram Showing Typhoid Fever in Chicago, 111. ... 164 Fig. 17. Diagram Showing Typhoid Fever in Cleveland, Ohio . . 168 Fig. 18. Diagram Showing Typhoid Fever in Cleveland, Ohio . . 169 Fig. 19. Diagram Showing Typhoid Fever in Burlington, Vt. . . 1 72 XX LIST OF ILLUSTRATIONS. xxi PAGE Fig. 20. Sketch of Brickyard Spring, Mount Savage, Md. . . . 189 Fig. 21. Map of Winnipeg, Manitoba 192 Fig. 22. Map of Winnipeg, Manitoba 194 Fig. 23. Diagram Showing Types of Epidemics 210 Fig. 24. Diagram Showing Relation Between Water Supplies and Tj'phoid Fever 229 Fig. 25. Diagram Sho^\'ing Relation Between Water Supplies and Typhoid Fever 230 Fig. 26. Diagram Showing Typhoid Fever in Frankfort-on-the- Main 231 Fig. 27. Diagram Showing Typhoid Fever in Newark, N. J. . . . 232 Fig. 28. Diagram Showing Typhoid Fever in Jersey City, N. J. . 233 Fig. 29. Diagram Showing Typhoid Fever in Lowell, Mass. . . 234 Fig. 30. Diagram Showing Typhoid Fever in Zurich, Switzerland . 236 Fig. 31. Diagram Showing Typhoid Fever in Hamburg, Germany 237 Fig. 32. Diagram Showing Typhoid Fever in Lawrence, Mass. . . 237 Fig. 33. Diagram Showing Typhoid Fever in Albany, N. Y. . . . 239 Fig. 34. Diagram Showing Typhoid Fever in Binghampton, N. Y. 240 Fig. 35. Diagram Showing Typhoid Fever in Watertown, N. Y. . 241 Fig. 36. Diagram Sho\^T[ng Typhoid Fever in Paterson, N. J. . . 243 Fig. 37. Diagram Showing Typhoid Fever in Paris, France . . , 244 Fig. 38. Diagram Sho\\ang Typhoid Fever in St. Louis, Mo. . . 245 Fig. 39. Diagram Shomng Typhoid Fever in Philadelphia, Pa. . 246 Fig. 40. Diagram Showing Typhoid Fever in Youngstown, Ohio . 249 Fig. 41. Diagram Showing Typhoid Fever in Washington, D. C 250 Fig. 42. Diagram Showing Typhoid Fever in Boston, Mass. ... 253 Fig. 43. Diagram Showing Typhoid Fever in New York City . . 255 Fig. 44. Diagram Showing Typhoid Fever in Brooklyn, N. Y. . . 257 Fig. 45. Diagram Showing Typhoid Fever in Baltimore, Md. . . 259 Fig. 46. Diagram Sho\ving Typhoid Fever in Lorain, Ohio . . . 262 Fig. 47. Diagram Showing Typhoid Fever in Hudson Valley . . . 264 Fig. 48. Diagram Showing Typhoid Fever in Glasgow, Liverpool and London 269 Fig. 49. Common Species of Flies " 297 Fig. 50. Diagram Illustrating Methods of Estimating Population . 304 INTRODUCTORY ESSAY TYPHOID FEVER: A DISEASE OF DEFECTIVE CIVILIZATION. By WILLIAM T. SEDGWICK TYPHOID FE\^R is a discovery of modern civiliza- tion. WTien Queen Victoria was born, in 1819, typhoid fever was unknown. \Mien she was ten years old it was just beginning to be recognized by a few pioneers as something different from tophus ("ship" or "jail" or "camp" or "spotted") fever, with which it had hitherto been everwhere confounded. TNTien she ascended the throne, in 1837, it was still generally unrecognized, even by progressive physicians. In a report on the Boston census of 18-45, published in 1846 by Lemuel Shattuck, an early and a singularly careful student of vital statistics, no mention is made of t\'phoid fever, but only of typhus; and it was not until after the middle of the nineteenth century that the disease became widely kno-mi in the United ^States, even to the medical profession. Its dis- covery, its name, its natural history, and the general recog- nition of its sanitary and economic significance, thus virtually coincide with the Victorian era, — a high tide in the history of civilization. It is still of frequent occur- rence in large civilized communities as widely separated as xxiv A DISEASE OF DEFECTIVE CIVILIZATION. Paris and Pittsburg, as well as in a host of smaller but no less civilized places. It caused in 1906, for example, 253 deaths in London, 639 in New York, 370 in Chicago, 122 in Boston, 161 in Washington. But while it is true both historically and as a fact of to-day, that typhoid fever is a disease of civilization, it ought to be clearly understood that it is only a disease of defective civilization, for it has gradually become notorious that the widespread or frequent occurrence of typhoid fever in any community must be due, somehow, to defective sanita- tion; and defective sanitation means defective civilization. It is also now generally believed that this disease, though specifically unknown, was really much more common and a much greater scourge of mankind before the Victorian era than it is to-day. The broad outlines of the natural history of typhoid fever have now been known for more than three quarters of a century. The particular parasite or microbe which causes it has been well known since 1884, that is to say, for almost a quarter of a century, and the principal habits, habitats, and means and modes of transmission of the microbe, nearly as long. The experience of various com- munities, some large and some small, in first extermina- ting and then for the most part keeping off the disease, has demonstrated the possibility of its control. It is therefore impossible to avoid the conclusion that communities in which typhoid fever abounds are either ignorant or care- INTRODUCTORY ESSAY. xxv less; and ignorance and carelessness are the ear marks of a defective civilization. And what is here true of cities, towns and other large communities, is equally true of the smallest, which is the family. The appearance of typhoid fever in any family, even in one member of it, is likewise evidence of defective sanitation, although, unhappily, the insanitation which thus shows its dangerous effects may have existed, not in the household or the family affected, nor even in the city, town or village of which it is a part, but on some remote and lonely farm, or some distant fruit ranch, or at the bottom of some quiet harbor planted with oysters but polluted with sewage. There is a fascination, a dramatic interest, in working out, even in imagination, the dark and devious paths and bypaths along which the microscopic parasites that afflict the human race travel to their appointed victims. Only the epidemiologist realizes the full meaning of the phrase, "the pestilence that walketh in darkness." All the skill of an expert detective is often required, — and often fails, — to discover the exact manner and the exact route by which typhoid fever was actually conveyed from one person to another; for while in some cases the way is clear and short, in others it is obscure and long. Those who read Mr. Whipple's account of various epidemics, notably that at Plymouth, Penn., in 1885, will perhaps realize in some measure what is meant by these statements. xxvi A DISEASE OF DEFECTIVE CIVILIZATION. It will be clear from what has already been said that typhoid fever is to-day universally regarded as a parasitic disease. A case of typhoid fever is probably as truly a case of parasitism as is a case of the itch, or of trichinosis, or of tape- worm; and the phenomena of the disease, or the sickness of the patient, are as truly the reaction of the organism to the attack of the parasite as are the galls of oak trees to the poison introduced by the gall fly, or the redness, pain and swelling which follow a mosquito bite to an attack by a mosquito, — that most familiar of parasites. In other words and from one point of view there is no longer any mystery about a case of typhoid fever. Each and every case comes somehow from some previous case. Whatever mystery there may be about it concerns the mode of transmission, — not the character of the causative agent. And yet, in common with other contagious and infectious diseases typhoid fever was for a long time thought to arise spontaneously. Trousseau, for example, said " La spontaneite est done un fait incontestable dans le developpment des maladies, mgme les plus contagieuses." Murchison went further and in his popular "pythogenic" theory assumed that typhoid fever " may be generated independently of a previous case by fermentation of fecal and perhaps other forms of organic matter ... it is developed by the decomposition of the excreta after their discharge." INTRODUCTORY ESSAY. xxvii To this last Dr. William Budd, of whom and of whose work more will be said beyond, pungently replied, " To conclude, on the evidence usually assigned for such a belief, that a poison, of whose growth this is the history, is bred in every cesspool or ditch in which there may chance to be a heap of seething rottenness, is precisely on a par with the philosophy which led the ancients to believe that mushrooms are bred of cow-dung, alligators of the mud of the Nile, and that bees, as Virgil sang, may be engendered in the entrails of a putrid ox." The rise of the germ theory of zymotic diseases and the discovery of specific parasites for the principal infec- tions laid to rest the time-worn theory of the spontane- ous generation of the poisons of the infectious diseases, and to-day the Eberth-Koch-Gaffky bacillus is everywhere regarded as the true parasite and sole exciting cause of typhoid fever. Contrary to the views of some, the parasite which pro- duces in its host what we call typhoid fever does not appear to be widely distributed in nature, if indeed it thrives at all "wild" outside the bodies of its hosts. The best proof of this is the fact that typhoid fever during an epidemic attacks very readily persons in poor health, the over- worked, those who are run down and the like; and yet persons of this sort may and do abound in any given community for years without suffering from typhoid fever, while on the arrival of some traceable infection of food or drink by typhoid parasites they speedily take and suffer from the disease. xxviii A DISEASE OF DEFECTIVE CIVILIZATION. The parasite of typhoid fever also seems to be com- paratively hardy. This at least is indicated by its frequent survival in water and milk, and its occasional occurrence in oysters, ice, air, sewage and elsewhere outside of the human body, which must probably be regarded as its most favorable habitat. For this reason it offers special advantages as a sanitary test or "sanitary index" of the general purity of food and drink as regards infectious microbes; the argument being that if this comparatively hardy parasite is absent, other infectious micro-organisms are probably absent also. If this one is present, it obviously matters comparatively little about others, since typhoid fever alone is sufficiently alarming. It is, of course, easy to show the inadequacy of this or any other single " sanitary index," since, for example, a milk free from typhoid has been known to cause hundreds of cases of scarlet fever. And yet it is roughly true that for any community which has constantly, year after year, a good record in respect to typhoid fever, the presumption is that sanitary con- ditions are at least fair. Strictly speaking, however, no such conclusion is justified, unless for the water supply, which, as far as is now known, is not, like milk, a ready vehicle of other infections. One of the most striking and important of recent ad- vances in our knowledge of the typhoid parasite is the fact that it appears to linger in the body of its recovered host, sometimes for months and even years, passing off INTRODUCTORY ESSAY. xxix from time to time in the excreta and infecting, or tending to infect, fresh victims. Every host is, of course, strictly speaking, during his ilhiess a "typhoid carrier," but by common consent this term is now reserved for survivors from the disease and others who in complete health con- tinue unwittingly to be a breeding ground for the bacilli and to discharge the typhoid parasites into their environ- ment. There is nothing unlikely or unprecedented about all this, for we already have in fact though not in name, diphtheria "carriers," i.e., persons who have, or even have not, had diphtheria, and yet show its germs in cultures taken from the throat. If the time ever comes, as seems likely will be the case, when a determination of the presence or absence of the typhoid parasite in the body can be made as easily, and as accurately, as is now done for diphtheria, a great step forward will have been taken. One of the first questions that arises when a case of typhoid fever appears in a family is whether or not the disease is contagious, and too often the family physician replies, "No: it is not contagious: it is only infectious." But in point of fact this question is as old as our knowledge of the fever itself, and has probably been the subject of more controversy than any other problem relating to the disease. When, for example, in 1829 typhoid was first clearly differentiated by Louis from typhus fever through the fact that the former alone is characterized by localized ulcers in the small intestine, that investigator noted XXX A DISEASE OF DEFECTIVE CIVILIZATION. that typhoid was contagious, though less so than typhus fever. Other workers alleged that one of the most dis- tinctive differences between the two was that typhus was, and typhoid was not, contagious. The two diseases were so much alike that many denied that they really differed, and apparently the desire to prove them different led to an exaggeration of the difference in respect to their con- tagiousness. However this may be, the truth is that the contagiousness of typhoid has been almost always under- estimated, and this in spite of the fact that Louis, who established the specific character of typhoid fever, Chomel, wh© gave to it its name, Bretonneau and Trousseau, in France, and Murchison and Sir William Jenner, in Eng- land, all asserted clearly and positively that it is a conta- gious disease. Chomel for example, observes (in 1834) that " there is a great difference of opinion among medical men, — the majority in France denying every kind of contagion in this disease," — their principal reason being, apparently, that of those surrounding the patient only a few take the disease. Chomel concludes that though plainly contagious it must be less contagious than many other diseases. Sir William Jenner, about 1850, after a careful study of typhus and typhoid fevers wrote : — " If typhoid fever be contagious it is infinitely less so than typhus. My experience leads me to regard it as contagious." Dr. Murchison, in 1858, gave it as his opinion that " typhus fever is eminently contagious. Typhoid fever is also contagious but in a more limited degree and possibly through a different medium." INTRODUCTORY ESSAY. .. xxxi Four years later he affirmed: " It may be communicated by the sick to persons in health, but even then the poison is not like that of smallpox given off from the body in a viru- lent form, but is developed by the decomposition of the excreta after their discharge. Consequently an outbreak . . . implies poisoning of air, drinking water or other ingesta, with decomposing excrement." Thus matters stood when, in 1873, the splendid and convincing work of Dr. Willliam Budd, an English physician, appeared, and proved beyond the shadow of a doubt that typhoid fever is a decidedly contagious disease. No student of typhoid fever should fail to read this remarkable volume and to make thereby the acquaintance of a master of keen and minute analysis and vigorous inductive reasoning. Tyndall has referred to Budd as " a man of genius withdrawn from the stimulus of the Metropolis and working alone at a time when the whole medical profession in England entertained views opposed to his." Budd's position was so strong that Professor Tyndall, whose ability to weigh evidence will hardly be questioned, was fully convinced and in 1874 wrote a strong letter to the London Times, saying, " How could a disease whose characteristics are so severely demonstrable have ever been imagined to be non-contagious ? How could such a doc- trine be followed out, as it has been, to the destruction of human life .-'" Dr. W. H. Corfield in 1874 went further, declared typhoid to be "virulently" contagious, and explained the differences of the contagionists and the anti-contagionists as follows : — " That it is contagious, and most virulently so, I have not the slightest doubt; but I quite imderstand what those mean who say it is not; they xxxii A DISEASE OF DEFECTIVE CIVILIZATION. mean that if you attend upon a patient suffering from typhoid fever you are not Hkely to get it, while if you attend on one suffering from typhus or scarlet fever you are very likely to do so, unless you have had the disease before ; they do not consider that this fact is not due to a difference in the contagious nature of the disease but to a difference in the form in which the poison is excreted from the patient, most of it being in the one case given out into the air which the attendants breathe, while in the other most of it is swamped in a mass of liquid which is removed as soon as possible. Those accustomed to smallpox, scarlet fever and the like, of course, said that typhoid fever was not contagious, when it was first brought to their notice, and there is no doubt that it is, under ordinary circumstances, very slightly so in their limited sense of the word ; but that is not what is meant by those who now deny that, except under certain circumstances, it is not communicable from one person to another." I have dwelt upon this matter at some length because the true contagiousness of typhoid fever is, even to-day, not recognized or taught as fully as it should be. No one pretends that typhoid fever is as contagious as small- pox or scarlet fever, or perhaps even as diphtheria. Doctor Corfield in the quotation just given has well stated the reasons why; reasons which, though formulated before the germ theory had been proven or the microbic parasite of typhoid fever discovered, are no less sound to-day. With the rise of that theory and the discovery of the parasites of the principal infections; with the brilliant achievements of epidemiology and the novel and startling discoveries of the role played by polluted water, polluted milk and other food materials, such as shellfish; with the astounding revelations of the damage done by insects as car- riers of malaria and yellow fever and plague ; the humbler, more insidious, and less spectacular part played by dirty INTRODUCTORY ESSAY. xxxiii hands, soiled linen, dirty bedding, dirty towels, dirty dishes, dirty forks and knives and spoons, dirty toys or playthings, dirty pencils, dirty candy or similar objects, handled or mouthed or kissed or sucked or spit upon, by persons having typhoid fever, have attracted but small attention. Yet it is to direct infection of this sort (which is what we mean by "contagion") that We probably have to look for a large part of that residual typhoid which still clings to many communities even after the water supply has been purified, the milk supply cared for and the various other public supplies controlled. There may have been a time previous to 1873 when a well informed physician in order to calm the fears of a family having a case of typhoid fever could have said conscientiously," You need have no apprehensions for the rest of the family; typhoid is not contagious, it is only infectious." But since Budd's great work, no scientific man, at least, would have dared to say as much. Those who depend on any such statement are living in a fool's paradise, for to-day it is a well known fact that even trained nurses in attendance on hospital cases where safeguards abound are often unable to escape an infection which is practically contagion; and this in spite of abundant knowledge, frequent warnings, and some painstaking. They may not have caught the parasites by touching their patients. They may have touched the patient's contaminated clothing, or bedding, or food, or utensils, or excreta. But between an infection so direct xxxiv A DISEASE OF DEFECTIVE CIVILIZATION. and so short-circuited and that which comes from actual contact with the person of the patient, there is no essen- tial or important difference ; and it is a satisfaction to one who, following William Budd, for years, and sometimes in the face of adverse criticism, has taught that typhoid fever is a contagious disease, to find that fact now more generally admitted, and even made popular among physi- cians by so good an authority as Conradi. " Twenty years ago I received letters describing to me the grief and ruin introduced into families through the notion, then prevalent, that typhoid fever is non-contagious. When Dr. William Budd published his researches on this subject, showing by facts and reasonings, as cogent as it was in the power of science to supply, the infectiousness of the fever, certain writers discerned in that important work a proof of the decadence of Budd's intellect and gave the public the benefit of their conclusions." (Professor Tyndall, New Fragments, p. 428.) One very disagreeable fact about typhoid fever is that it is intimately associated with human excrements. Diphtheria parasites are probably cast off chiefly in the sputum. Bacillus tuberculosis, according to some recent ideas, is given off freely by tuberculous cows in their milk, their sputum and their excrement. But since the lower animals do not have typhoid fever, man is the only source of the peculiar parasites of this disease, and though the germs may occur in the spit and sweat it is believed that they occur most often and most abundantly in the urine and feces of typhoid fever patients. Hence it follows that if water, milk, oysters, etc., convey these germs, they have probably been contaminated by human excrement. Such INTRODUCTORY ESSAY. ^xxv contamination often arises by the way of sewage pollution of foods and drinking water supplies. But if the recent discoveries relating to typhoid " carriers " are correct and logically interpreted, they indicate a more direct, more personal and more disgusting contamination of food and drink by servants and others of unclean habits, and compel us to assume an easy transfer of filth from one person to another through contact of excrements with food or drink. To overcome this disgusting condition, which is far too common, nothing will suffice except education in personal hygiene or, what ought to include this, careful home train- ing. Sanitation can effect the purification of public water supplies, but it cannot either induce or compel waitresses to wash their hands before passing from the water closet to the china closet. This, only education or training can do, and until they have done it, unclean ser- vants will continue to be what they are to-day, a serious menace to personal and family, as well as public, health. The statement is often made that " for every case / typhoid fever some one ought to be hanged." j. • „ striking saying and worth remembering, because-. . .i responsibility for this disease where it be! ^ i„ ^ "^ -ongs, namely, upon mankind, and not upon fate or the g^ i -p . „j,iggg hanging is to be introduced as a penalty ^^^ j^^^^^^ce and neglect, it is not often true. What ; ^^^^ j^ ^^^^ ^^^^y case of typhoid fever comes from so^^^^^^^,^ ignorance or neglect. And here also the reme^.^^ ^^^ education and xxxvi A DISEASE OF DEFECTIVE CIVILIZATION. training, with penalties only for criminal negligence. We might more truly say that for every case of typhoid fever some one ought to be educated. And just here Mr. Whipple's work is certain to do great good. Itself a remarkable witness to the variety of inter- ests concerned with or affected by typhoid fever, it is important also as a demonstration of the intimate relations already established and to-day rapidly increasing between sanitary biology, preventive medicine and sanitary engi- neering. " For we are not dealing here with questions of which the interest is absti-act only . . . but with a matter which, take the world over, for every year that passes is life or death to myriads of men. . . . " And let no one suppose that this is a matter in which he has no personal interest. This disease not seldom attacks the rich, though it thrives most among the poor. But by reason of our common humanity we are all, whether rich or poor, more nearly related here than we are apt to think. The members of the great human family are bound together by a thousand secret ties of whose existence the world in gen- eral little dreams. And he that was never yet connected with his poorer neighbour by deeds of charity or love, may one day find, when it is too late, that he is connected with him by a bond which may bring them both to a common grave." (William Budd, Typhoid Fever. London, 1873.) \ \ TYPHOID FEVER. CHAPTER I. TYPHOID FEVER. Typhoid fever, or enteric fever, is an intestinal disease, caused by a microbe kno^^^l as "Bacillus ty- phosus," or more commonly as "B. typhi," or "the typhoid bacillus. " Through the multiplication of this germ within the body, with the consequent production of a poisonous substance, which, for want of a better understanding, may be termed typhotoxin, morbid con- ditions are produced in various parts which give rise to the characteristic symptoms of the disease. Ulcer- ations of the intestines and enlargements of the mesen- teric glands and spleen are the most pronounced of these lesions; but being transported by the blood the bacilli often invade other organs of the body, — the kidneys, the liver, the lungs, the bone-marrow. Symptoms. The symptoms of a typical case of typhoid fever are well defined, but so many exceptional or atypical cases occur, and the early symptoms are so often indistinct, that errors in diagnosis are not uncom- mon. The most characteristic symptoms are a gradually increasing and regularly fluctuating temperature, general 2 TYPHOID FEVER. prostration, diarrhea (or perhaps constipation), frontal headache, nose-bleed, dry cough, enlarged spleen, rose- rash over the abdomen and sometimes elsewhere, gas- eous distension of the intestines, emaciation, and, in severe cases, intestinal hemorrhages, and delirium. These symptoms cover an average period of four or five weeks, but they may be preceded by a week or two of general malaise, and are followed by a rather long period of convalescence, during which relapses are not infrequent. Fatal cases usually terminate during the fourth or fifth week of the disease, or after a relapse. Diagnosis of typhoid fever cannot often be made within four or five days after the onset, as many of the symptoms may be wanting in any particular case. The presence of the rose-rash or a positive bacteriological test of the blood are usually necessary to make the diagnosis certain. A Typical Case. A typical case of typhoid fever is likely to give the following medical history: Between the time when the typhoid bacillus enters the body and the time when the patient realizes that he is seriously ill, there is a so-called incubation period, or prodromal period, which usually lasts about two weeks, but which may vary from one week to three. During this time the health may be apparently unaffected, but more often the patient feels played out, loses appetite, and "aches all over." The true onset is generally accompanied by symptoms which compel the patient to take his bed and call his physician. There may be shivering, or perhaps a chill, headache, a coated tongue; perhaps nose-bleed or a bronchial cough; fever, rest- TYPHOID FEVER. 3 lessness and insomnia, muscular weariness, thirst, nausea; there may be either diarrhea or constipation. These symptoms continue during the first week, the tempera- ture gradually rising to 103 or 104 degrees at night, with a corresponding increase in the morning tempera- ture, which is lower than at night, the pulse also show- ing a slight elevation. During the second week most of the symptoms become worse, but headache and nausea disappear. The temperature rises to 104 or 105 degrees, w^ith morning remissions of one or two degrees; the pulse rises to 100 or no and becomes weaker. Prostration and apathy become great, the voice feeble, the tongue dry and brown. The bowel discharges are frequent and loose, pale yellowish brown in color, and more or less lumpy. About the eighth or tenth day rose-spots about one-eighth of an inch in diameter appear on the abdomen, coming and going in successive crops, lasting only a few days each, and disappearing altogether during the third week. Nervous tremors become conspicuous, and there may be some delirium. During the third week the night temperatures continue high, but the morning remissions may be somewhat lower. The patient becomes emaciated, semi-conscious, and perhaps delirious. The stools may become tinged with blood, the urine lessened in amount. During this week, pulmonary complications are most likely to develop, — sometimes pneumonia. During the fourth week night temperatures slowly fall to 102 or loi degrees, while the morning tempera- tures begin to approach normal, even becoming sub- TYPHOID FEVER. 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CO 'Wd .rr IM 'Wd cc:] ■H -WW tj' tu W 'Wd i 3 O 'Wd < r-l -W V Pi. -i-iS _;.-. . 'W*d *^^ZX. ^ 'WV 1 ' ' ' ^?'' ~ ^ 'Wd ■«;' HI ■" -WV 1 p ' H Jd ^ *Wd T? n I- -ws 1 > ^ .^ 'Wd i ■s. ■"■'' h 'V -Wd c- 1 1 1 1 ' CO .„., i'— ;^s-n ' ■ C5 ■"■'' -'-^•' 1 ; '■ ' r 1 " "i^ ' rt "Wd 1 ij \\-^X. t^ S EC °t- ^«0 °»C °-*l °CO °<3 O O C5 O O 2i § ("aHVd )'3anj.va3dW3i TYPHOID FEVER. 5 normal in some instances. With lower temperatures all the symptoms tend to improve, the pulse grows stronger, the mind becomes clear, the tongue becomes moist, and the patient begins to desire food. The fever sometimes persists for a few weeks longer, but usually the fifth week begins the period of convales- cence, which may last anywhere from two or three weeks to as many months, and if no complication sets in the patient recovers. Indiscretions in eating, in exercise, or exposure, however, may cause a dangerous relapse, during which there is a repetition of the original symp- toms. The second attack is seldom as severe as the original one; but, on the other hand, the reserve strength of the patient is correspondingly less, so that relapses are always to be dreaded. Treatment. Good nursing, proper diet and hygiene, and the free use of the cold bath, effect a cure in from 90 to 95 per cent of the cases. Medicinal treatment aimed directly at the disease counts for little, and thus far no antitoxin has been found to counteract the effect of the bacterial poison similar to those which have ac- complished such marvelous results with diphtheria and tetanus. Medical treatment is devoted rather to assist- ing the various organs of the body to perform their normal functions under the unusual conditions, to prevent any overstrain on any weak organs, and to ward off, as well as possible, any unusual complications. Nature practically cures the disease, and both nursing and medical treatment are adjusted so as to give Nature as free a hand as possible in doing so. Complications. It is said that not over a third of 6 TYPHOID FEVER. the deaths from typhoid fever are due directly to the effects of the disease, i.e., to the effects of the typho- toxin. Two-thirds of the deaths are due to the numerous compHcations, among which pneumonia and tuberculosis are prominent. This is a most important matter to sanitarians in connection with death certificates. " Walking " Cases. Some cases are so mild that they are not recognized as typhoid fever at all. The patient, though not feeling well, remains up and goes about his usual pursuits. Ultimately he may recover without knowing he has had the disease, or he may suddenly become seriously ill. Such cases are called "walking" cases, and for obvious reasons they are especially dan- gerous to the public. Children, particularly, are liable to have mild attacks of typhoid fever which go unrec- ognized. It seems probable also that a person may harbor the typhoid bacillus without having the disease at all. Reference to the so-called "typhoid carriers" is given on a later page. Details of the various symptoms, methods of treat- ment, studies of exceptional cases, complications and after-effects, are important matters to be considered from the standpoint of the patient and of the physician, but less so from that of the sanitarian, whose interest lies chiefly in those things which concern the transmis- sion of the disease or which affect the vital statistics. So far as the disease itself is concerned the most impor- tant facts for him are those which throw light upon the probable date of the infection and the duration of any particular case. Allied Diseases. There are several intestinal diseases TYPHOID FEVER. 7 closely allied to typhoid fever, milder in character, and not as definite, either in their pathology or bacteriology. That which is most like the typical disease is knowoi as parat}'phoid fever. This term has not vet come into common use among practicing physicians, and its systematic position is not \vell established. Many bac- teriologists, however, recognize the paratyphoid bacillus as distinct from bacillus typhosus. Then there is a certain t}'pe of dysentery caused by the Shiga bacillus, — in fact there are several varieties of this bacillus. These dysenteries are sometimes termed '"'infantile cholera," " "winter cholera," "summer complaint," etc. Then there is, of course, the true Asiatic cholera, which is similar to typhoid fever in its modes of transmission. If this were a medical book it would be appropriate to discuss these allied diseases, but as the factors that influence their transmission are very largely the same as in the case of typhoid fever, and as the bacteriology of the diarrheal diseases is in an uncertain and con- troversial state, no further reference to them will be made. CHAPTER 11. BACTERIOLOGY OF TYPHOID FEVER. The typhoid bacillus was discovered by Eberth in 1880, and soon afterward was isolated and studied in pure culture by Koch, Gaffky, and others. It has been known to science only a quarter of a century, yet in that time it has been the subject of research by hundreds of investigators working in many lands. A mere list of the titles of the papers which have been written about typhoid fever would fill a volume of considerable size. Yet with all this study we know but little about the inner structure of the organism, little about its physiology, and little about the conditions which affect its behavior inside, or its longevity outside the human body. The little that we do know, however, is of great practical importance, and, considering the difficulties involved, is most creditable to the new science of bacteriology. The Typhoid Bacillus. ' The typhoid bacillus is a minute vegetable cell, cylindrical in shape, with rounded ends, one to four microns long (o.ooi to 0.004 mm.), or, say, 10,000 to 25,000 to the inch, and per- haps a third as wide as it is long; with no characteristic interior structure, no indication of spores, but covered on the outside with numerous long, undulating flagella which. give the cell powers of lively motion in liquid BACTERIOLOGY OF T^THOID FEVER. 9 media. The germs multiply by fission, — that is, by cross splitting, — each cell becoming two, and each two, four. Ordinary Appearance. Stained to show the Flagella. Growth of the Bacilli in the Spleen. Appearance of the Bacilli in the Widal Test, before and after " clumping." Fig. 2. THE TYPHOID FEVER BACILLUS. Magnified about i,ooo Diameters. and so on. Under the microscope, cells may be often seen in the act of dividing, — some with an elongation. lO TYPHOID FEVER. some with a slight constriction, and some appearing as two cells attached; occasionally chains of divided cells may be seen, looking like links of microscopic sausages, but moving with a serpentine motion. So minute that half a million would scarcely cover the head of a pin, they have enormous vital power, and they increase so " rapidly in certain artificial culture media that in two or three days a hundred may become a billion, and form colonies, or masses, visible to the naked eye. It is more by the study of these mass cultures and by the effect which their growth produces on the culture media than by the study of the individual cells, that the germs are identified. Without entering into the details of bacte- riological technique, suffice it to say that by the com- bined study of morphology, physiology, and cultural characteristics, the typhoid bacillus can be recognized in the laboratory, isolated in pure culture, and submitted to various tests as to virulence, and longevity in various environments. Specific Cause of the Disease. The question is often asked, How do we know that the so-called typhoid bacillus is the specific cause of the disease? It must be admitted that the direct proof is not as complete as in the case of some infectious diseases, for the reason that the lower animals are not, so far as known, susceptible to the disease. Horses, dogs, cats, guinea pigs, rabbits, etc., do not have typhoid fever. This closes the door on a most important field of research. The proof, there- fore, must be of necessity circumstantial in character, except as accident has resulted in the direct infection of human beings with pure cultures of the organisms BACTERIOLOGY OF TYPHOID FEVER. II isolated and cultivated from a previous case of typhoid. But, though largely circumstantial, the evidence is never- theless of the very strongest kind. The Eberth bacillus can be isolated from persons sick or who have been sick with typhoid fever, and from those persons only. It is present in the blood and is found in enormous numbers in the urine and feces of typhoid patients. Water infected with such discharges has repeatedly been found to cause the disease in others. Peculiar and intimate relations have been established between the blood serum of typhoid patients, or of those who have recently had the disease; and pure cul- tures of the Eberth bacilli. Such blood, when added to broth cultures of the bacilli, causes a cessation of motility and a clumping, or agglutination, of the organ- isms not produced by the blood of a person who has not had the disease. (Fig. 2.) Although animals do not suffer from the disease of typhoid fever, laboratory experiments have demon- strated that cultures of highly virulent typhoid bacilli introduced into rabbits and guinea-pigs have produced some of the symptoms of the disease and have caused death. In these experiments the most pronounced pathological conditions have been in the region of the intestines, and in some cases the bacilli have been recovered from the affected parts. In general, however, animal experimentation has given negative rather than positive results. There are, however, a few cases on record where typhoid fever has been contracted by workers in the laboratory who accidentally became infected with cultures of the bacillus. 12 TYPHOID FEVER, In spite of lack of direct experimental proof that the bacillus of Eberth is the specific inciting cause of typhoid fever, the circumstantial evidence is so strong that bac- teriologists and sanitarians are satisfied that this bacillus is the true and only cause of the disease. Portals of Entry. The typhoid bacillus enters the body through the mouth, by ways hereafter described, and passes through the stomach into the intestines. That the germ can enter the body through any other portal than the mouth and intestinal tract is doubtful, although some pathologists have claimed that in rare cases it enters 'through the lungs. The gastric juice, because of its acid character, tends to destroy the bacillus, and this, no doubt, prevents many a case of the fever. There would seem to be some advantage, then, in drinking water, if its quality is suspicious, at the close of a meal rather than before or between meals. Typhoid bacilli taken into the stomach at a time when there is a vigorous secretion of the gastric juice probably stand less chance of reaching the intestines alive than if swallowed at times when the stomach is riot performing its digestive functions. Multiplication in the Body. Having arrived in the intestines the bacilli find conditions more favorable for growth, and especially so in the lower third of the small intestines, where the inflammation and ulceration are most conspicuous. Just what occurs is not known, but it is thought that they force their way through the enfeebled membranes, enter the lymph and blood- channels, and are swept on through them to the spleen and other parts of the body. Multiplying in the so- BACTERIOLOGY OF TYPHOID FEVER. 13 called Peyer's patches and the glands of the intestines, the bacilli produce the characteristic ulcers. They accumulate in the spleen in enormous numbers, giving rise to a characteristic congestion of that organ; they may also accumulate in the liver, the gall bladder, the kidneys, the bladder; they have been found even in the lungs, the meninges, the saliva, the rose-spots, the mar- row of the bones, and, what is of great importance, the blood. It is even believed by some that gall stones are of typhoidal origin. Recent studies have shown that the germs are present in the blood in practically all cases during the entire course of the disease, but they are especially evident during the early stages. In fact some pathologists go so far as to state that during the first week of the disease typhoid fever is a septicaemia. Coleman and Buxton, who have made a careful investigation of this subject, have given data showing that in over a thousand cases in which the blood was examined, 89 per cent were found to have the germ in the blood during the first week, 73 per cent during the second week, 60 per cent during the third, 38 per cent during the fourth, and 26 per cent after the fourth week. They found that the period during which the germ was present in the blood corre- sponded to the duration of the fever symptoms. The appearance of the germs in the blood marks the onset of the disease, while their disappearance from the blood marks the beginning of convalescence. Some think, however, that the bacilli do not multiply in the blood, but that on the contrary, they " overflow " from the spleen and other organs into the blood and 14 TYPHOID FEVER. there die and liberate the toxin against which the body reacts. Just how the typhoid bacilli penetrate the tissues of the intestines and get into the lymphatic system is not well known. That many persons take the germs into their system without succumbing to the dis- ease seems certain. That persons whose systems are run down or enfeebled from overwork or exposure take the disease easier than persons in robust health is also certain; but that persons in robust health do not contract the disease is far from being the case. A recent theory which has been accepted by some German pathologists is that the invasion of the intestinal walls by the typhoid bacillus is due to the presence of certain intestinal parasites, or worms, which penetrate the walls and thus allow the bacilli to enter. American patholo- gists have not as yet accepted this theory, and the weight of evidence appears to be against it. Another theory that is attracting the attention of pathologists is that much of the so-called summer typhoid is due to the occurrence of other intestinal disorders which act as exciting causes, rendering the intestines more susceptible to the inva- sion of the typhoid bacilli than at other times. Another theory is that improper diet, giving rise to a congestion of the liver, may reduce the secretion of bile and thus deprive the intestinal tract of a natural disinfectant which tends to prevent adventitious bacteria from caus- ing trouble. Others believe that the white blood cor- puscles act as carriers of the bacilli from the intestines into the lymphatic system. Still another idea is that a first infection predisposes a person to acquire the disease BACTERIOLOGY OF TYPHOID FEVER. 1 5 after a subsequent infection and that this "hypersensi- tiveness" has much to do with the incubation period of the disease, — the original attack rendering the blood susceptible to its greater infection when the bacteria "overflow" from the spleen. These and similar theories have yet to be proved. They may be more or less true, and some of them certainly seem reasonable; but it is hardly necessary to resort to them, in view of the kno^Mi ability of the tubercle bacillus to pass through the intestinal mem- branes, and of the demonstrated ability of the typhoid bacillus to pass through parchment and collodion mem- branes. Typho-toxin. During their growth the typhoid bacilli are active in producing a specific toxin which is liberated in the blood, and it is the reaction of the body against this which, in great measure, is responsible for the well- known symptoms of the disease. Depressing the powers of vital resistance, various organs become affected, and bronchitis or pneumonia may become established, the heart action may be weakened, and the nervous system deranged. Typhoid fever is therefore a disease which operates partly by the direct influence of the bacteria, and partly by the indirect influence of the poison which they produce. Natural Defenses of the Body. As a natural defensive reaction against further invasion of the typhoid bacilli, there is to be found in the blood-serum of typhoid patients a bacterioh-tic substance which is inimical to the growth of the organism. The nature of this substance is still shrouded in mystery, just as is the nature of typho- 1 6 TYPHOID FEVER. toxin itself, but that it tends to destroy the typhoid bacilli seems certain; though whether it neutralizes the effect of the poison which they produce, is less certain. It, no doubt, plays an important part in checking the disease and in rendering patients immune from a second attack. Attempts have been made to take advantage of this "antibody " to effect both prevention and cure of the disease, but thus far with little or no success. It has proved very useful, however, in diagnosing cases of typhoid fever by means of the so-called Widal test, often referred to as the "blood test for typhoid fever." Widal Test. If a drop of blood from a person who has, or who has recently had, typhoid fever be mixed with 30 drops of sterile distilled water, and a drop of this mix- ture added to a drop of a broth culture of typhoid bacilli, and examined under the microscope, it will be noticed that after a few minutes the bacilli, which at first are motile and are uniformly scattered over the field of view, gradually become motionless, and then aggregate themselves into compact masses. This is known as the phenomenon of agglutination, or "clumping." This will not happen with the blood of a person not ill with the disease, or one who has not recently had it; nor will it ordinarily happen during the first few days of the dis- ease. Neither will it happen if the blood of a typhoid patient is mixed with a culture of some other organism. ^ A positive Widal test obtained on the blood of a sus- pected case — that is, one in which clumping is observed — is therefore practically conclusive evidence that the ' There are some exceptions to these general statements, but they do not militate against the main propositions. BACTERIOLOGY OF TYPHOID FEVER; 1/ disease is typhoid fever. Conversely, the blood-serum of a person known to have had typhoid fever, or of an animal which has been rendered immune to the effect of injected cultures of the organisms, may be used to establish the identity of an unknown culture of bacteria, although this test is less definite in its results than the other. Various modifications of the original Widal test are now practiced. Dead cultures are used instead of the living typhoid bacilli, and the precipitation of the clumped bacteria in mass is substituted for the microscopical examination, thus simplifying the test, though probably at the sacrifice of accuracy. Blood Tests. Perhaps a better test than the Widal reaction is the direct examination of the blood for the presence of the typhoid bacillus. This is accomplished by drawing a small quantity of blood from the ear or from a vein at the bend of the elbow into an all-glass syringe, and putting from i to 3 cubic centimeters of it into a flask containing 20 cubic centimeters of sterile ox-bile culture medium, and, after cultivation, examin- ing this for the presence of the typhoid bacillus accord- ing to the method described on page 322. Modes of Exit. That the typhoid bacilli are present in the body of every patient has been firmly established. How do they leave the body? In what numbers? In what condition ? How long do they persist ? These and similar questions are of great importance in considering the spread of the disease. As typhoid fever is very largely a disease of the intes- tines, the bacilli ought obviously to be found in the dis- charges of the bowels. Bacteriological studies have 1 8 TYPHOID FEVER. shown that they are so found. They are especially abundant during the earher stages of the disease, but decrease in numbers as the patient convalesces. They are more numerous in diarrheal discharges than in the more solid lumps of fecal matter. How long they persist in the bowel discharges after the patient is well, is not known, and the period naturally varies greatly in dif- ferent individuals. In most cases no danger is to be feared after the patient has recovered; but it is the part of wisdom to consider the stools as suspicious, and to maintain disinfection, for at least two weeks after apparent recovery. In the "typhoid carriers" the feces may be infected for months and even for years. No reliable figures are to be obtained for the number of bacilli in the bowel discharges, but the numbers for a single evacuation may easily exceed one billion; and there is ample reason to believe that the bacilli leave the body in a living and virulent condition. The presence of the bacilli in the kidneys and bladder of many patients naturally causes the urine to become infected. Until within a few years this was overlooked, and the disinfection of urine was not considered as of great importance. Although the urine is not infected in all cases, it is now considered that its disinfection is even more important than that of the feces. Whenever the urine is infected, the numbers of typhoid fever bacilli found in it are enormous. Sternberg cites a case where each cubic centimeter of a patient's urine contained 175,000,000 bacilli. This would amount to approxi- mately 200,000,000,000 a day. Furthermore, the bacilli frequently persist in the urine for several weeks after BACTERIOLOGY OF TYPHOID FEVER. 1 9 convalescence and after the practice of disinfection is ordinarily discontinued. For these reasons urinary infection is more to be feared than fecal infection. In some cases the bacilli are found in the mouth and throat. Consequently the saliva may contain them. This condition may be infrequent, but it is always liable to occur. There is practically no danger to be feared from the quietly exhaled breath, as bacteria do not readily leave a moist surface; but coughing or sneezing may cause the expulsion of the bacilli into the atmosphere, with conse- quent dangers to persons in the room who may inhale them. The sputum of a typhoid patient is likewise a possible source of infection, especially in those cases where pneumonic symptoms are prominent. The bacilli have been found in the perspiration; and although the danger from this source is probably quite remote, it is one that ought not to be overlooked. Generally speaking, it may be said that it is chiefly in the urine and the bowel discharges that the typhoid bacilli leave the body of the patient, but in some cases they may leave by way of the nose and mouth, or by even the perspiration. Typhoid Carriers. While it seems generally true that the body becomes quite free of typhoid bacilli within a comparatively short time after recovery, recent studies have shown that in a very small percentage of cases the germs may persist for months and even years. Such persons become "typhoid carriers." They may be in good health, and yet be a constant source of danger to others — all the more dangerous because unsuspected. 20 TYPHOID FEVER. European observers found that about 3 per cent of 1782 cases examined by them became typhoid carriers, and a few cases of this kind are on record in this country. One of the best known is that of "Typhoid Mary," a cook in New York City, who, in good heakh, and changing from place to place, left a trail of at least twenty-eight typhoid cases in the houses where she had served, until the facts were finally found out. • Bacteriological studies made by the health department showed that she was a "typhoid carrier." Typhoid fever bacilli were found in her feces. To prevent her from being a further menace to the community, the department of health placed her in a hospital and are endeavoring to effect a permanent cure. There is reason to believe that typhoid carriers may develop from "walking cases" and even from those who are not cognizant of having had the disease. Such cases are probably quite rare, but they are especially danger- ous, and no doubt account for some of the "sporadic " outbreaks, that is, for the sudden occurrence of the disease in places where it was never before known to occur and where there was no apparent cause. CHAPTER III. THE TYPHOID PATIENT AS A FOCUS OF INFECTION. Modern sanitary science declares that every case of typhoid fever is caused by an infection with bacilli derived from some previous case of typhoid fever. Sometimes there is direct contact between patient and victim; but more often the victim is unknown to the patient, and far removed in time and space. The modes of conveyance of the bacilli may not always be known, but the "bactenotogyn^f - to-day~ir[Slslf°llmt~there--m«&t_be 'some mode of conveyance, and that the disease cannot be produced by bad air, bad water, bad food, faulty plumb- ing, or by climatic conditions, however unfavorable, -4h^4:yphoidJ)acillus is involved. The Endless Chain. Sanitary science declares further that every case of typhoid fever is potentially a focus of infection; that virulent bacilli may and do leave the patient's body; and that unless proper precautions are taken, these bacilli may become scattered in various ways, and ultimately give rise to new cases. In former days the spread of typhoid fever went on as an endless chain, like the mailing schemes in which one sends a begging letter to five persons, and each of these sends a similar letter to five other persons, and so on. To break this chain as near as possible to the original 22 TYPHOID FEVER. link is the aim of modern sanitary science. It is a task which cannot be accomplished single-handed; it requires the cooperation of the patient, the attending physician, the nurse, the members of the household of the patient, and the public health authorities. Each has a responsi- bility which cannot be shifted to others. Barriers against Spread of the Disease. Every typhoid case should be surrounded, as it were, by a series of barriers, through which, in order to escape, the typhoid germs must pass. Should the germs pass the first line of inclosure, they should be held by the second; and should they pass the second, they should be retained by the third. If these barriers could be faithfully maintained the -ravages of the disease would soon be checked ; but through mischance or ignorance, or more often through negligence, some bacilli do escape through all the barriers and become scattered at large. Vehicles of Infection. Through various agencies the vagrant germs are carried to their victims. Some of these agencies are well known; but there are, no doubt, others not yet brought to light. Carriage by water is one of the most important modes of transmission, and the one which, by reason of the magnitude of its effects in large communities and the spectacular character of frequent epidemics, has most attracted the attention of the public. Transmission by flies from infectious matter in the privy to food in the kitchen, i.e., from improperly guarded fecal discharges to unscreened houses, is probably of common occur- rence, especially in summer and in rural districts, and may be one of the chief causes of the summer and FOCUS OF INFECTION. 23 autumnal typhoid. It has come to be well recognized also that milk, oysters and other shell-fish, raw fruits and vegetables from gardens fertilized by human ex- crement or handled by persons sick of typhoid, may carry the bacilli. Contagion. Nor must transmission by contact, that is, by contagion, be overlooked. A patient who sneezes into his nurse's face; a convalescent who handles a piece of cake or some dainty and passes it to another member of the family, or who shakes hands with a visiting friend, or who uses the " family towel," may unwittingly spread the disease. Typhoid fever is both contagious and infectious. For the sake of clearness and emphasis, these various modes of transmission are expressed diagrammatically in the frontispiece, together with the barriers which should surround the patient, and certain lines of defense which should be established to protect other individuals from the typhoid bacilli at large. First Barrier. The first fight against the spread of typhoid bacilli must be made in the sick-room. It may be fairly as- sumed that the patient is ignorant of the nature of his disease until he calls the doctor, and the family physician is ordinarily the first to diagnose the case. The initial responsibility for preventing the scat- tering of the bacilli, therefore, rests with him. Duty of the Physician. The first duty of the physician is, of course, towards his patient; but his second is towards the other members of the household, and his 24 TYPHOID FEVER. third to the community; and the physician who neglects the last two should be considered guilty of malpractice as truly as he who neglects the first. The conscientious physician acts in a dual capacity, — as medical adviser and as sanitary guardian ex-oficio. Modern medical treatment of typhoid fever does not aim directly at destroying the bacilli in the body, but rather towards the maintenance of normal functions in order that the body may protect itself. From the stand- point of the patient this is doubtless the proper policy; but there is good reason to believe that without injury to the patient, physicians can do much more than they ordinarily do to reduce the number of bacilli discharged from the body. Intestinal disinfectants have little or no value in controlling the disease, but disinfection of the bladder and the urinary tract by the use of urotropin and similar drugs is a pronounced success, and its prac- tice ought to become more common in typhoid cases. With proper precautions the danger of spreading typhoid fever by infected urine could be largely eliminated. Disinfecting washes for the mouth might also be of some use, but in most cases the condition of the patient is such that they could not be used. Although the physician can do much to prevent the typhoid bacilli from leaving the body of the patient, it cannot be expected that any treatment will be wholly effective. Disinfection of the discharges is therefore always necessary, and, all in all, it is the most important sanitary precaution to be taken. Duty of the Nurse. Disinfection must usually be done by the nurse or attending member of the family, FOCUS OF INFECTION. 2$ but it should be ordered by the physician according to regulations established by the board of health. The original responsibility is with the physician. As soon as it is even suspected that a case is one of typhoid fever, disinfection should be prescribed. If the physician assumes that the members of the household are ignorant of the subject, he will be right in nine cases out of ten. He ought therefore to give most explicit directions as to what disinfectants to use and how to use them. Too often the physician's directions are given in an indefinite and perfunctory manner, and are carried out in the same spirit. Suppose "chloride of lime is ordered": the well-meaning but inefficient attendant sprinkles a Ifttle of this substance around, keeps it up as long as the patient is in bed, and then everybody forgets about it. Suppose he "orders corrosive sublimate," and cautions against its poisonous character: the result is that the attendant is either too much scared to use it in a proper manner, or is so reckless that there is danger of poisoning the whole family. He may "order the bedding to be disinfected": and this may be done a few times; but if the laundress finds that the chemicals are rotting the clothes or turning them dark, as will doubtless happen, the practice is very likely to be given up. Disinfection. People do not like the smell of chloride of lime or carbolic acid, and in consequence too little of these chemicals is used, and the period of contact with the matter being disinfected is insufficient. In some places the chemicals recommended by physicians can- not be easily obtained. The writer recently investi- gated an epidemic in a town where neither chloride of 26 TYPHOID FEVER. lime, formaldehyde, or even corrosive sublimate could be obtained, even though the town had a drug-store. The question of expense also enters into the problem in some cases. The result of this is that in the majority of typhoid cases which occur among the poorer classes, disinfection as now conducted by the "doctor's orders" is a mere farce, while among the more intelligent people it is often insufficient. Few indeed are the physicians who closely follow up their first instructions and personally see that they are carried out. Nor ought they to be required to do so outside of the house. The disinfection and disposal of typhoid excreta is a matter of public concern, and should be supervised by the local board of health, just as much as rooms in which diphtheria and scarlet fever cases have been confined are disinfected. It cannot be expected that the actual work be done by a public health agent, as it is something which requires attention several times a day; but the board of health should furnish the chemicals, and see that they are used in a proper manner. In this matter physicians and the board of health should act in harmony. The board of health should prescribe the method to be used, and the physician should act as its agent in instructing the family of the patient as to the necessity of disinfection and as to the modes of procedure. Report to Board of Health. If the responsibility for the disposal of infectious matter is to rest with the pub- lic authorities, they must be promptly informed as to the occurrence of the disease. In many states and in most cities the sanitary regulations require physicians to report FOCUS OF INFECTION. 27 cases of typhoid fever as they occur; but there is an almost universal carelessness among physicians in report- ing cases, which is most discreditable to the profession, as it shows not only a lack of appreciation of the value of public sanitation, but an utter disregard for law. Study of statistics shows that very seldom are half the urban cases of typhoid fever reported to the board of health, while very often not one case in a dozen is turned in. Health officers who are responsible for the enforce- ment of the registration laws should be far more strict, and should not hesitate to exact full penalty from those physicians who fail to do their duty. The existence of an epidemic in a community is frequently not recognized until delayed reports accumulate in the office of the board of health, or until local gossip or the local press has called attention to it. Many days of valuable time which might have been used in searching for the cause of the disease, or in inaugurating a system of prophylactic measures, are thus lost, and it is no exaggeration to state that many lives have been needlessly lost because of the failure of physicians to report their cases promptly. One reason for greater slowness in the reporting of typhoid fever cases than those of other diseases is the uncertain character of the disease in the early stages and the lack of well-defined symptoms. Some allow- ance must be made for this; but if suspected cases were reported, the authorities could often be of assistance to the doctor by making blood tests and analyses of fecal matter to confirm or disprove the diagnosis. There are three things, therefore, which the physician 28 TYPHOID FEVER. can do to prevent the spread of typhoid bacilH: first, to adopt such measures with the patient as to reduce as far as possible the number of bacilli which leave the body; second, to order the disinfection of the feces, the urine, the sputum, the bedding, etc., according to the requirements of the board of health; and third, to report the case, as soon as suspected, to the board of health, in order that the public authorities may supply the needed disinfectants and superintend the disposal of infectious matter. This work, for which the physician is responsible, constitutes the first barrier against the spread of the disease. Second Barrier. Duty of the Household. If the walls of the sick- room mark the boundaries of the first barrier, the second line of inclosure is that which surrounds the premises in which the patient dwells. Some typhoid bacilli are sure to pass out of the sick-room, and upon the nurse and attending members of the family devolves the real task of extermination and control. The need of this task will be understood from what has been said regard- ing the exit of the typhoid germs from the body of the patient, and the various modes of conveyance of these germs to new victims; but for the sake of emphasis they may be listed as follows: 1. Disinfection of fecal matter. 2. Disinfection of urine. 3. Disinfection of sputum and vomited matter. 4. Disinfection of water used in bathing the patient. FOCUS OF IXFECTIOX. 29 5. Disinfection of bedding, clothing, towels, nap- kins, handkerchiefs, sponges, used about the patient. 6. Disinfection of knives, forks, spoons, cups, etc., used by the patient. 7. Disinfection of the hands of the attendants, 8. Proper disposal of feces, urine, etc., by burial in the ground, or in water-closet or privy, as occasion demands. 9. Disinfection of water-closet or privy seats, and privy vaults and cesspools. 10. Screening of privy vaults to prevent access of flies. They might be summed up, however, in two words, — disinfection and cleanliness. Disinfectants. The disinfection of infectious matter from typhoid patients is not at all difiicult. The typhoid bacilli do not form spores and are easily killed. The chemicals required are not expensive, and may be easily and safely manipulated. It is necessary, how- ever, to use the disinfectants in large enough quantities, to thoroughly mix them with the discharges, and to give them time enough to act. Many different disinfectants have been recom- mended, — chloride of lime, corrosive sublimate, carbolic acid, formaldehyde, copperas, blue vitriol, and others, — and all of these have certain special advantages in particular cases; but all in all, for common practical use, there is no better substance for the disinfection of fecal matter, urine, or sputa, or for use in privy vaults 30 TYPHOID FEVER. or cesspools, than slaked lime freely used. It has the important advantage of cheapness and availability; it is without odor, and is such a well-knovm substance that no one fears its use. It is conspicuously white, so that its use is evident to the inspector. Being cheap, it is naturally used in large quantities, and this insures a.' more intimate contact with the infected matter. The other disinfectants named are perhaps more active chemical agents than lime, and smaller amounts may be used; but chloride of lime and carbolic acid and for- maldehyde all have odors which people dislike, while corrosive sublimate is a powerful poison and has to be used with caution. For hospitals and for cases where trained nurses are employed, corrosive sublimate and carbolic acid are perhaps the most serviceable. So, too, for the cramped quarters of city apartments. But for use in isolated country houses, and among the more ignorant class of people, common lime is preferable. In disinfecting the typhoid discharges, especial attention should be given to the feces in the earlier stages of the disease, and to the urine in the later stages. Even after convalescence the urine she uld be disinfected for several weeks, or until a bacteriological examination has shown it to be unnecessary. Bedding and clothing soiled by the patient should be soaked for several hours in a solution of car- bolic acid or bichloride of mercury, and afterwards washed in boiling water. Handkerchiefs should be similarly treated, though, preferably, inexpensive cloths should be used for the sputa and afterwards burned. Spoons, cups, and other articles handled by the patient FOCUS OF INFECTION. ' 31 should be soaked in disinfectants before washing; and, as a further precaution, certain particular articles of this character should be set apart for the exclusive use of the patient. Detailed instructions for the use of disinfectants are given on page 287. Disposal of Fecal Matter. After two or three hours of contact with the disinfectants, the fecal matter, urine, etc., must be disposed of. WTiile standing they should be carefully covered to protect them from flies. In houses provided with water-closets connected with the public sewers this is the natural and proper place of disposal, but in country places burial in the earth is preferable to disposal in a privy or cesspool. The earth for a foot or more down from the surface is teeming with bacteria and other forms of life, and when typhoid bacilli are buried in the ground they are soon destroyed. Care should be taken in the selection of a spot. It should not be near a weU, nor in a garden where garden truck is raised. A convenient mode of burial is to dig a trench a foot deep, throwing the earth to one side and covering each deposit as soon as it has been placed in the ground. The urine, as well as the solid matter, should be poured into the trench and covered, and not poured on the top of the ground, as is too often done. During the winter, when the ground is frozen or covered with snow, burial in the earth should not be attempted. It is better to use the privy or cesspool, and thoroughly disinfect it and clean it as soon as there is opportunity. Above all things, the discharges should 32 TYPHOID FEVER. not be put on top of frozen ground. This procedure has been the cause of some of the most severe epidemics that have ever occurred in this country. If the discharges are thrown into a privy vault, this should be thoroughly disinfected with lime, and each new deposit should be immediately covered with lime. The back of the vault and the windows and ventilators of the privy house should be carefully protected from flies by means of screens; all cracks should be covered with paper pasted over them; a self-closing seat cover should be used, and a spring should be placed on the door to render it self-closing. If the discharges are thrown into a cesspool, or into a water-closet which connects with one, it should be dis- infected most thoroughly, and great care should be taken with the material removed at subsequent cleanings. In fact, to guard against future danger the cesspool should be emptied and disinfected as soon as the infected sewage has ceased to flow into it. Cleanliness. Above all things, scrupulous cleanli- ness is required on the part of the attendants, both in the interest of self-protection and that of preventing the spread of the disease to other members of the family. This is especially necessary in the sick-room. A drop of urine or a speck of fecal matter no larger than a pin-head may contain hundreds of thousands of bacilli; hence care against the spattering of such matter is important. In caring for a patient, the hands of the nurse are very likely to come in contact with infectious matter. Wash- ing and disinfecting the hands after leaving the bedside are therefore demanded. A careless attendant going FOCUS OF INFECTION. 33 from the bedside to the kitchen and there preparing the family meals may convey the disease to the whole household. Cases are on record where this has occurred. Isolation. The isolation of the patient is important. He should have a room by himself, or at the very least a bed by himself. In crowded quarters this is often difiicult of attainment. The author once saw a man sick with typhoid fever in a room occupied by fifteen others, there being four beds occupied by Hungarian laborers who worked in day and night shifts, and the woman who took care of the beds and tended the patient prepared the food for the sixteen men. In such a case the only recourse is to remove the patient to a hospital. While isolation of the patient is desirable, a strict "quarantine," in the sense in which the word is gen- erally used, is unnecessary. The sick-room should be thoroughly screened to prevent flies from carrying about the infection. Children. Children should not be permitted to run in and out of the sick-room, or to share with the patient the dainties which are so often furnished. Their inquisitiveness and their innocent desire to be of service to the sufferer often result most disastrously. The convalescing patient must remember that he is liable to be a focus of infection for a number of weeks after he leaves his bed, and should take unusual care not to infect other members of the family. The work of disinfection and the care exercised by the household of the typhoid patient thus constitute the second, and most important, barrier against the spread of the disease. 34 TYPHOID FEVER. Third Barrier. Duty of Public Authorities. The final responsibility for the prevention of the spread of typhoid fever rests with the public, acting through the board of health, or the health officer, or other properly constituted authority.- This demands the exercise of various activities, such as, — 1. Consideration of reports of physicians. 2. Diagnostic tests. 3. Supervision of the disposal of infectious matter. 4. Distribution of disinfectants. 5. Purification of sewage. Before the board of health can act in a case of typhoid fever, it must have a knowledge of the existence of the case, which should come to it from the physician. Stringent laws requiring doctors to report their cases promptly should be passed and rigidly enforced. Many doctors hesitate to report cases for fear that their reputation may suffer through an occasional faulty diagnosis. If, however, the law required suspected cases of typhoid fever to be reported, there would be no such feeling; and if a second report should reverse the decision of the first, or if the blood test should give a negative result, no harm would be done. The failure to report a case of real typhoid fever works far greater damage than the report of a suspected case which proves to be something else. System of Reporting. Everything should be done to make the work of reporting typhoid cases as easy and automatic as possible. Physicians are busy men, FOCUS OF INFECTION. ' 35 irregular in tlieir hours, and often away from home for a large part of the day. Suitable postal card blanks, stamped and addressed, should be freely supplied to the doctors, and arrangements should also be made for report by telephone. The nature of the physician's report is referred to on page 218. Blood Tests. The board of health, having received the report of a suspected case, should be prepared to verify the same. This involves the application of the Widal test to the blood of the patient, or some equivalent test, and requires the services of a bacteriologist and a laborator}^ equipment. Most of the large cities are now able to do this work; but in the case of small com- munities which cannot assume the entire expense, it should be done by the county or state, or conducted on some cooperative basis. Results of these tests would not only be of great assistance to the physician, but they would greatly strengthen the position of the board of health in the matter of disinfection. The board of health should also be prepared to make bacteriological examinations of the feces and urine of convalescing patients. These tests are coming to be regarded as quite as important as the "Widal test. Supervision over Disinfection. The board of health should maintain a general supervision over the dis- infection of typhoid excreta, and should establish regu- lations and secure the cooperation of the physicians in having them carried out. It should provide all needed disinfectants and distribute them in proper receptacles, accompanied by simple but full directions for use. The gain to .the community by this public 36 TYPHOID FEVER. distribution of disinfectants would more than justify its cost. Sewage Disposal. Leaving the household we now come to the larger question of the disposal of the sew- age and other wastes of the community. These are emphatically public matters, though they fall within the domain of the engineering departments of a city rather than that of the department of health as ordinarily constituted. A number of years ago, a sewerage system was con- sidered to be complete if it satisfactorily collected, with- out nuisance, the sewage from the houses and let it go somewhere, anywhere, into the harbor, into the lake, or into "the river, according to situation, — out of sight, out of mind. Sewer gas was regarded as dangerous; the sewer liquid was regarded merely as a nuisance. Now this is reversed, and the liquid sewage, germ-laden" and infected, is known to be the thing to be most feared. Sewage disposal is therefore now looked upon as quite as important as sewage collection. Recent years have seen some extraordinary developments in the art of sewage purification, and coming years are destined to see far greater advances. There is a good deal of misconception about the subject of sewage disposal. Sanitary problems are not necessarily involved, although they usually are to some extent. In some places it may be merely a question of nuisance, — and it must be remembered that a stream which has bad odors and which is offensive to the sight will not cause typhoid fever, unless the typhoid germs are in the water, and unless the water gets into the mouth. FOCUS OF INFECTION. 37 This is not the place to discuss the general subject of sewage disposal, but a few facts are worthy of notice at this point. There are various methods of sewage purification, some of them of modern date, involving septic tanks, chemical precipitation basins, contact beds, sprinkling filters, etc. These and similar agencies are usually installed for the purpose of improving the chemical character of the sewage, and to prevent its subsequent decomposition, with attendant nuisances. If properly built and properly operated, and enlarged from time to time according to need, they do in a satisfactory manner the work for which they were designed; they even do more, — they accomplish a marked bacterial purification of the sewage. But their chief function is to destroy dead organic matter, not living organisms, — although living organisms are concerned in the process. They do not render sewage fit to drink; and if the effluent is turned into a stream used for drinking, some danger of con- tamination still remains. Such systems reduce the danger of contamination, but they do not wholly remove it. In this respect the old systems of purifica- tion by intermittent filtration and broad irrigation are more to be depended on, but even these processes are not complete. There is a growing feeling among sanitarians that noth- ing less than a secondary filtration of a sewage effluent, carried out substantially on the lines of water purification, or a disinfection of the effluent by means of chemicals, is necessary in order to render sewage free from patho- genic bacteria. 38 TYPHOID FEVER. Whether or not the sewage of a city or town should be purified to such a degree as to destroy pathogenic bacteria, is a question which must depend upon the local surround- ings, and must be decided independently for each particu- lar case. If the sewage of a city flows into a stream used in its lower reaches for purposes of public water-supply, that city is at least morally bound to keep infectious matter out of the river. The courts are beginning to decide that where a city is supplied with public sewers the municipality is respon- sible for any damage occasioned by the pollution of a stream by this sewage. Although thus far this decision has been applied only to cases of nuisance, in time it may be extended to cover cases of infection. Disposal of Fecal Wastes on Boats and Trains. The disposal of water-closet wastes on steamboats and trains is something that demands serious consideration. The pollution of the water of lakes from steamboats pass- ing near a water-works intake, and the scattering of fecal matter along the road-bed of a railroad, passing over some water-shed used for public supply, are likely to bring disaster. Although the chance of danger may be small in comparison with other causes of typhoid fever, yet the practice is unsanitary and disgusting. In some places trains passing through territory tributary to a water-works reservoir are compelled to have their closet doors locked. While this prevents contamina- tion of the road-bed, the continual damage to the health and comfort of passengers by reason of deprivation of toilet privileges might easily be a more serious matter than the chancp of damage done to some water-supply. FOCUS OF INFECTION. 39 The practice is only to be tolerated as a temporary expedient. What is needed is some form of receptacle to be used on the train that will hold the urine and excreta until they can be safely removed at the end of the journey or at some intermediate point. There is cer- tainly ingenuity enough among our railroad men to provide some device that will do this without nuisance to the passengers. The present toilet-room arrange- ment in the ordinary day coaches is usually an abomi- nation. Care of Toilet-Rooms. The lack of care of the toilet- rooms in most railroad stations is another wrong that needs righting. Used promiscuously by the careless, the ignorant, the sick, they are seldom cleaned, and rarely or never disinfected, while flies swarm through the windows, and vermin crawl on the floor. This is more likely to be the case in small way stations than in the terminal stations of large cities. What is true of railroad toilet-rooms is true to some extent of factories, schoolhouses, and public buildings. All such toilet-rooms open to the public or used by large numbers of people should be under regular inspec- tion by the health authorities, and occasional disinfection should be required by law. Flies. The public authorities can help to prevent the spread of typhoid fever, as well as other diseases, by bringing about conditions of general cleanliness. "Dirt breeds disease." One cannot tell how far this trite saying extends, but every year bears new testi- mony to its truth. Flies, which may be often the means of transmitting typhoid fever germs, develop from eggs, 40 TYPHOID FEVER. and these eggs are very commonly laid in manure piles. Dr. L. O. Howard, the entomologist of the United States Department of Agriculture, states that the house-fly prefers horse-manure as a breeding-place, although it may breed in other fecal matter. Dangers may arise from the location of stables in crowded communities, and hence strict rules should be made in regard to the care and storage of manure. The disposal of garbage is also an important matter, as the common little fruit- fly is likely to be the means of conveying the typhoid bacillus. The war on flies has scarcely begun; when it does begin, it will involve many reforms. Among these will be cleaner streets, and especially the prompt removal of horse-manure, better care of stables, better care of vacant lots, better care of wharves and markets, better protection of garbage pails, and a general attempt to eliminate the breeding-places of flies and insects. More attention will be given to screening public build- ings, schoolhouses, hotels, restaurants, etc. In these various ways the public authorities, represent- ing the whole people, can establish a final and exceed- ingly important barrier against the spread of the typhoid bacillus. CHAPTER IV. THE TYPHOID BACE^LUS AT LARGE. It is easier to keep the pig from getting out of the pen than it is to catch him when he is out. It is easier to keep the sparks from scattering from the fireplace than it is to put out the conflagration that the sparks have kindled. So, also, it is easier to prevent the germs of typhoid fever from leaving the sick-room than it is to avoid them, or to discover and destroy them, after they are out of bounds. But, in spite of all precautions, sparks will sometimes scatter, pigs will get loose, and typhoid germs will escape through all the barriers. Our next study, therefore, must be the typhoid bacillus at large. The Typhoid Bacillus Outside the Body. Bacillus typhi is essentially a parasitic organism. A common habitat, and apparently its favorite one, is the human body. There it may find for a time conditions favorable for growth. Unfortunately, however, it does not die as soon as it leaves the body, but, unless destroyed, maintains a vagabond existence in various places and for various lengths of time, ultimately perishing of exposure or starving to death, or, with better luck, finding once more a temporary home in the intestines of a new human host. The whole story of the saprophytic existence of the 41 42 TYPHOID FEVER. typhoid bacillus — that is, its life outside of the body — is far from, being known, but much has been learned during the last ten or fifteen years regarding its longevity in different media, and the influence upon it of heat and cold, dryness, pressure, oxygen, food-supply, poisons, etc. How long will the typhoid fever bacillus live in water? How long in ice? How long in milk? In the soil? In ^oysters ? How does its vitality when it leaves the body affect longevity? And how does environment affect its virulence? These are some of the questions which the sanitarian needs to have answered, and they are among the most difficult and complicated problems which the bacteriologist is called upon, to solve. Little wonder that the experiments thus far made have not been in entire accord and that experts have sometimes disagreed on these important matters." Requirements for Growth. The three principal re- quirements for bacterial growth are food, moisture, and warmth, but many other factors affect longevity. Some of these are of a general character, but most of them may be most conveniently discussed under the heads of water, milk, ice, and the soil. Moisture. Moisture is essential to the growth of the typhoid bacillus, as it is to all vegetable life. Drying is for this organism more fatal than it is to many forms, and even a short period of desiccation results in death. Some bacteria, as, for instance, the bacillus of tetanus, form spores which are provided with a firm cell-wall that enables them to withstand drying. They are able to maintain a latent existence, as a seed does^ and then, after a period of inactivity, THE TYPHOID BACILLUS AT L.\RGE. 43 when the conditions become favorable, germinate and multiply once more. It is for this reason that the dried sputum of a consumptive is to be feared, and it is for this reason chiefly that dust is dangerous. But, so far as is now known, the typhoid bacillus does. not form spores, and there is little or no danger to be feared from dust or from the air, unless this dust or this air has had opportunity for recent infection. The danger from dust should not be wholly ignored, for, although no spores of the typhoid germ have ever been discovered, experiments have indicated that among the many individual cells of a culture, a few often seem to have powers of resistance against an unfavorable environment far above the gen- eral average. Furthermore, a particle of dust dried only on the outside may harbor living germs within. GeneraUy speaking, however, drj^ing kills the typhoid bacillus. Typhoid germs do not readily leave a moist surface. Sticky by nature, they adhere until desiccation loosens their dead cells. For this reason sewer air is not to be looked upon as a direct means of infection. Experi- ments have shown that the air of the Paris sewers con- tains fewer bacteria than the air in the streets above them. Laborers who work in sewers are not more afflicted with air-borne infectious diseases than other laborers. The exhaled breath is practically sterile. One may blow for some time through a tube into a sterile culture medium without contaminating it. But the constant breathing of sewer air, or "sewer gas" as it is often called, may have a depressing effect on the system, and render one less liable to resist infection. The 44 TYPHOID FEVER. exhaled breath during coughing and sneezing may con- tain a spray of saHva that may be dangerous. Sunlight. Sunlight is a strong germicide. It has been often shown by laboratory experiments that cul- tures of typhoid bacilli and other bacteria exposed to the direct rays of the sun in a window are quickly killed or their numbers greatly reduced. The solar energy is a powerful aid to desiccation in rendering dust in- nocuous. "Letting in the sunlight" is not merely a figure of speech, it is one of the most powerful and ben- eficial of sanitary measures. It is a common belief that sunlight exerts a potent influence in the purification of water in lakes and streams. To a certain extent this is true, but its effect is not as great as one might naturally expect, and often it is nil. The energy of the sun's rays penetrating a body of water is so rapidly absorbed in the upper strata that even at a few feet below the surface it has only a very small fraction of its value at the surface. This is the case in clear, colorless water: in waters which are muddy the absorption of light is even greater, and the sterilizing effect does not extend more than an inch or so below the surface. Many interesting experiments have been made to determine the intensity of the energy of the sun's rays as they pass downward into bodies of water. Photographic plates have been exposed at different depths; the decolorization of water has been studied; and sealed bottles of water containing known numbers of bacteria have been kept at different depths for equal intervals of time and the numbers of bacteria remaining ascertained. All of these experiments indicate that THE TYPHOID BACILLUS AT LARGE. 45 whatever sterilizing influence is possessed by the sun's rays is confined to a very thin layer, and that the more turbid or discolored a water is, the thinner is the stratum affected. Temperature. The temperature relations of the typhoid bacillus are very important. The most favorable temperature for its development is probably that of the human body, namely, about 98.6 degrees F., or 37 degrees C. At much higher temperatures, and at much lower temperatures, according to laboratory experi- ments, growth in culture media is less rapid. Above 50 degrees C. (122 degrees F.) no growth occurs, while at the pasteurizing temperature (60 to 65 degrees C, or 140 to 160 degrees F.) practically all germs are killed even with an exposure of a few minutes. Boiling is, of course, a fortiori fatal. Milk pasteurized for ten or twenty minutes, or water brought to the boiling-point, may be therefore considered as practically safe from typhoid infection. Typhoid bacilli grow luxuriantly in laboratory culture media at room temperature (20 degrees C, or 68 degrees F.). At lower temperatures their growth is checked, but is not entirely stopped even near the freezing-point. Freezing does not necessarily destroy bacterial life, though it has an important influence on longevity, as elsewhere mentioned. Food. Like other bacteria, the typhoid bacillus requires a food-supply of organic and mineral matter, but the exact nature of its requirements both as to quantity and quality has never been determined. It is known, however, that so small an amount as one part 46 TYPHOID FEVER. of organic matter in a million parts of distilled water will materially prolong its existence. This amount of organic matter would be obtained by putting about one drop of milk in a gallon of water. The Longevity of the Typhoid Bacillus in Water. The typhoid bacillus does not multiply in ordinary drinking-water, even though the water be polluted. On the contrary, natural water is an unfavorable medium, and from the time when the germs enter a stream or a lake or a well or the salt water of the ocean, there is a constant dying off of the bacilli. The weaker cells die first, and there is generally a rapid initial reduction in numbers, due perhaps to the effect of plasmolysis, that is, 'to osmosis. Later the decrease is less rapid, but continues until all but a few bacilli have disappeared: ultimately all the cells die. This is the present con- ception of sanitarians, reached after a great amount of experimentation and the study of many epidemics. Decrease of Typhoid Bacilli in Water. The rate at which the bacilli decrease in water varies very greatly, as might be naturally expected. Laboratory experi- ments are far from being in perfect agreement on this point. In some of the experiments almost all the bacilli have disappeared at the end of three to five days; in others ten per cent have lingered for a month. In very cold water the mortality is rather more rapid than in waters at summer temperature; in waters which are well oxygenated it is less rapid than in stagnant waters deficient in oxgyen; in waters rich in organic matter the longevity THE TYPHOID BACILLUS AT LARGE. 47 is greater than in distilled water, but in nature this is more than offset by the antagonistic influence of the more common water bacteria and of other organisms higher in the scale of life. If, for the purpose of illustration, one wished to use definite figures to show the rate of decrease of typhoid fever bacilli in ordinary drinking-water under ordinary conditions, it might be said that after a week the water may contain 30 per cent of the number added, after two weeks 10 per cent, after three weeks 3 per cent, and after a month or six weeks i per cent or less. A fairer method of presentation, however, and one which gives latitude for different conditions, is shown by the following diagram, in which the curve illustrating the percentage decrease in number would fall somewhere within the shaded area. Time is evidently a most important element. Age does as much for water as it does for wine. The Resistant Minority. It will be noticed that the curve in Fig. 3 does not fall quite to the zero line; in other words, the bacilli do not wholly disappear within the time indicated. This brings up a very interesting point, the importance of which is gradually impressing itself oh the minds of bacteriologists. In almost all of the recent experiments which have been made to deter- mine the longevity of typhoid bacilli exposed to unfavor- able influences, such as heat, cold, freezing, or the action of various disinfectants, it has been noticed that a few individual cells seem to have greater powers of resist- ance than the general mass of cells in the culture. For example, occasionally bacilli may be found alive in milk 48 TYPHOID FEVER. h5 _oo uj-< ^~ IjEO JC ujPb HZ I_ water or milk. :r ei: ::od the purity of which is open to question, at the ei. I : : i — eal rather than at the begiiming, or, as some onr Izi^ :i??tiously stated it, " Never eat on an empty stc ~ i : /. 7 h.e reason for this is that during digestion :Jie f ;~ :: zistric juice is in- creased; hence, typhoii zer-ii :i2rT. ir_:o the systein after digestion has beg".:-" 5:1^1 ieii ciiizie of mimina the gauntlet of its eneziie; in :i.e E::~i;ii ml n^rer in:r -in- than at tiie beginning :: ::-: meii. "rien the digesdve faculties are Irmin: n.e ;er~ i- n :re likely to find conditions fi :r^.ie :: ir ri::nnen:. Although httle has been said about it in the text-books^ aif d although it has not been scientifically demonstrated, many physiologists apparently believe that there is much truth in this theory. Risks of Trave ling . The individual can to some extent protect himself by the avoidance of known typhoid fever risks, especially when traveling. To drink tiie dty water at the present time in Philadelphia or HttsbuEg, or in any other city where the supply is notoriously polluted, is to take an unwarranted risk; to eat oysters in dieap restaurants in New York or Balti- — :re. where the supply is partly derived from contam- ini:el s'lrces, is also a risk; to drink milk at an ordi- nnr resrn-irant is a risk. Many traveling men have ccme :: jnierstand these dangers and to avoid them. Ti'e ri: i:e i -:raping celery before eating it; of re- m inr e " ei :r'~ apples; the custom of washing the iiinli -e:::-r i niei... and other matters of ordinary LEilS :? ZZ7Z2'SZ 91 I—&C130SL. :^T)ei' or to demanstri :ti ::z i_t : jdjumaiy way i.:r:-:L is ^— ^1- Im r-^sidiQial cdk amril about: CHAPTER VI. TYPHOID FEVER STATISTICS. We now come to the mathematics of typhoid fever, a subject interesting chiefly to the speciaHst, and naturally considered as dry; yet to one who takes pains to under- stand the statistics, and who has the imagination to look beyond the figures and see the facts for which they stand, these records of death tell a wonderful story. They measure the steady progress of sanitary science down the years, and foreshadow the coming of the day when the scourge of typhoid fever shall be all but swept away; they also reveal many a sad case of official ignorance and carelessness, and many an instance, besides, of patient and unrewarded public service. But, if the records of typhoid epidemics tell a story of shame in many an American city, they also show that our cities are learn- ing from their experiences, and that almost everywhere there is an increasing desire to provide good water, good milk, and generally improved sanitary conditions. The statistics afford also many illustrations of cause and effect in sanitary matters, and demonstrate in striking ways the soundness of the gospel of cleanliness. The histories of typhoid fever epidemics illustrate the brilliant detective work that has been done by our sanitary experts, and 92 TYPHOID FEVER STATISTICS. 93 show that the "bug catcher" has come to be a most important member of the community. In a volume of this size it is impossible to give more than a condensed summary of typhoid fever statistics, to describe in an elementary way what they mean, and to guide the reader where to look and what to look for in studying the subject more in detail. Nature of the Statistics. Typhoid fever statistics may be considered in two groups, — first, those which appertain to the individual case, and, second, those which refer to the community, the second being practically a general and condensed summary of the first. The unit data, show- ing when and where a patient was taken sick, and all the particulars relating to an individual case, are necessary in the study of particular epidemics, but they are of less general interest than the summarized statistics of the second group. The statistics for the community may be subdivided into two classes, — those which relate to sickness, and those which relate to death; that is, morbidity statistics and mortality statistics. For reasons already pointed out, the morbidity records are less likely to be accurate than the mortality records, the law^s regarding the filing of death certificates being much better lived up to than those requiring physicians to report their typhoid cases to the health authorities. Consequently our study will concern itself chiefly with the mortality statistics. Death-rates. One of the terms most commonly used in sanitary science is the "death-rate." By this is meant the ratio which the number of deaths in a com- munity in a given time bears to the living population. 94 TYPHOID FEVER. The unit of time is generally one year, while the unit of population is taken as looo, 10,000, or 100,000, accord- ing to custom or convenience. To illustrate the mean- ing of "death-rate": If twenty persons should die in one year in a town which has a population of 1000, the annual death-rate would be said to be " 20 per 1000"; if thirty persons died in one year in a town which has a population of 1500, the annual death-rate would again be "20 per 1000"; — in other words, the calculation of the death-rate is merely one of simple proportion. The object of using the term "death-rate" is to enable one to compare on the same basis the sanitary con- ditions in communities which differ in population, and in the same community at different times. When the term "death-rate" is used alone, it generally means the annual ratio of deaths from all causes to the living population. When specific diseases are in question it is customary to speak of the " typhoid fever death-rate," the "diphtheria death-rate, " etc. General death-rates are usually calculated on a basis of 1000 population, as the figures thus obtained are most convenient for tabulation. Death-rates for particular diseases are sometimes cal- culated on the same basis or on the basis of 10,000, but it is more common to calculate them on the basis of 100,000 population, as this tends to avoid the use of deci- mals, and simplifies tabulation. Thus, when the average annual typhoid fever death-rate for the United States is given as 35, it means that of every 100,000 of the popula- tion 35 persons die from typhoid fever each year. All the typhoid fever death-rates referred to in this volume have been calculated on this basis. TYPHOID FEVER STATISTICS. 95 Monthly death-rates could be calculated in a similar way, by finding the ratio between the number of deaths in the month and the living population, and expressing the result as so many per 1000, or 10,000, or 100,000. The sum of the monthly death-rates for the year would thus equal the annual death-rate, it being assumed that the population does not change. When, however, it is desired to compare the mortality in any month with the average mortality, the monthly death-rate for the month in question is multiplied by 12, so as to show what the annual death-rate would be if it were the same for the whole year as for this one month. This method is more commonly used, perhaps, than the other. It has the advantage of maintaining a single unit of comparison. Similarly death-rates may be calculated for weekly periods, and reduced to their equivalent annual death-rates. It will be seen that there are three elements involved in the calculation of typhoid fever death-rates, — first, the number of persons who died of the disease; second, the population of the community; and third, the period of time during which the deaths occurred, generally taken as one year. The accuracy of the death-rate depends, therefore, upon the correctness of the number of deaths reported, and the correctness of the estimate of population. In the study of typhoid statistics it is important to bear this fact in mind; and, as both quanti- ties are likely to be in error, too much attention must not be given to very slight differences in calculated death- rates. In order to avoid errors due to incorrect population returns, the typhoid fever statistics are often figured on 96 TYPHOID FEVER. the basis of total deaths; that is, instead of calculating the number of typhoid deaths per 100,000 population, the rate of the typhoid deaths to 100 deaths from all causes is found. This figure may be termed the "percentage of typhoid fever." The method is useful in comparing the relative importance of different diseases. It serves as a sort of check on the death-rate. Figures are given sometimes to show the fatality of the disease, — that is, the rate of deaths to cases. To illustrate the meaning of these different terms, we may assume that a certain community, which has a population of 20,000, had in one year 400 deaths from all causes, 15 deaths from typhoid, and 250 cases of typhoid; then: The total death-rate would be 20 per 1000; The typhoid fever death-rate, 75 per 100,000; The percentage of typhoid fever, 3.75 per cent, and The fatality of typhoid fever, 6 per cent. Sources of Error. One of the most important sources of error in typhoid statistics is the faulty diagnosis of the disease. The experience of the Spanish war taught that many so-called cases of malaria were really typhoid fever, while probably some cases were called typhoid fever that were really due to improper diet. Dr. Ful- ton, of Baltimore, has shown that this is true to-day of much of the malaria in the southern states. The cases are much fewer, however, where true malaria is diagnosed as typhoid fever. In the past, when diagnosis was based wholly on symptoms, there was some excuse for the con- founding of these two diseases; but now that we have TYPHOID FEVER STATISTICS. 97 the bacteriological tests for typhoid fever, and can detect the malarial parasite in the blood by microscopical examination, such errors are in most cases inexcusable. As a matter of fact, there has been a decided improve- ment in diagnosis in recent years. The tendency of this more exact diagnosis has been to increase the amount of typhoid fever given in the statistics; and this fact must be borne in mind in making chronological comparison, and in comparing the typhoid fever death-rates in malarial and non-malarial regions. Another source of error in the statistics is due to the confusion resulting from complications in the disease. It was said above that less than half of the typhoid patients who die, succumb from the direct effects of the disease; more die from the effect of the comphcating, or secondary diseases. Thus, a person may get typhoid fever, and before this disease has run its course pneu- monia may set in, and the patient may die from the latter cause. The physician should, of course, report this as a case of typhoid fever; but he may report the death as due to typhoid fever or to pneumonia, or he may call it, as he often does, typhoid-pneumonia. Sanitarians are at variance as to the proper course to be pursued in this case. If the pneumonia was due to an invasion of the lungs by the typhoid bacillus, the death should unquestionably be reported as typhoid fever; but if the pneumonia was due to the pneumococcus, there is more reason for calling it pneumonia, and whether it were called typhoid fever or pneumonia would probably be determined in the mind of the physician by the time that elapsed before the secondary infection took place. 98 TYPHOID FEVER. It would appear to be logical to report such a case as typhoid-pneumonia, or typho-pneumonia; but this term has been so much abused, and has been so much used to describe severe cases of pneumonia where there was no typhoid infection at all, that sanitarians are now almost unanimous in condemning the use of the double term. Physicians are sometimes too explicit in reporting causes of death. For example, a lady in Maine, accord- ing to an old record in a city clerk's office, is said to have died from "typhoid fever, bronchitis, pneumonia, and a miscarriage." From the standpoint of epidemiol- ogy, it would be preferable to classify cases according to the first infection; but as the vital statistics are not to be used alone for a study of epidemics, there is some objec- tion to this course. In important investigations it is always advisable to refer back to the original death certificates. Greater uniformity is desired in these •matters, and the uncertainties are here mentioned merely to warn the reader to be on his guard in studying typhoid statistics, and not to give too much weight to published records. There has been recently organized in the American Public Health Association, a Section of Vital Statistics for the purpose of considering all questions relating to this subject. TJie old records of typhoid fever in many places are liable to be in error by reason of incompleteness, and in studying the statistics it is wise to take into account the date when adequate registration laws were put in force. In generalized statistics minor errors became less prominent, so that in spite of all the inaccuracies which the typhoid fever records of the country contain, they TYPHOID FEVER STATISTICS. 99 are sufficiently exact to show the main facts in regard to the relative abundance of the disease in different places and at different times. Morbidity Statistics. The incompleteness of morbidity statistics of typhoid fever based on physicians' reports, is usually so great as to make them practically useless. A few examples will suffice to illustrate this : In Brooklyn, N.Y., in 1904 there were 1050 reported cases of typhoid fever and 303 deaths, indicating a fatality of 29 per cent; in New York City (borough of Manhattan) in the same year there were 2136 cases and 309 deaths, indicating a fatality of 14.5 per cent. When complete statistics are obtained, the percentage fatality in typhoid fever almost never exceeds 10 per cent. In Waterville and Augusta, Me., where in 1902-3 statistics were obtained by a house-to-house canvass, the fatality was 8.6 per cent; in Ithaca in 1903 it was 6.1 per cent; in the United States military camps during the Spanish war it was 7.6. The fatality varies according to age, as referred to elsewhere. When an epidemic occurs, physicians are more likely to report cases of typhoid fever than at other times when there is no excitement. Thus, in Cleveland, the ratio of typhoid deaths to reported cases in 1902 was 27 per cent; during the epidemic years of 1903-4 it was 14.5 per cent; in 1905, after the excitement had subsided, it rose to ^^ per cent. It is not infrequent that health department records will show a larger number of deaths from typhoid fever than there were cases reported. For this reason, in the study of epidemics it is necessary to take special steps to secure accurate data. lOO TYPHOID FEVER. Sources of Information. Those who desire to know the typhoid fever situation in their own town or city or state, should consult the reports of the local board of health or the reports of the state board of health, if they are published; and if they are not, they should then seek the original authorities, by going to the officials charged with keeping the records of death certificates. The United States Bureau of the Census published in 1900 a rather complete series of statistics for that year for a portion of the United States known as the "regis- tration area," and the same bureau now publishes annually the typhoid fever death-rates for the principal cities of the country. These data are issued in the form of bulletins, which can be obtained by writing to the Director of the Census, Washington, D.C. From the same source can also be obtained a table of the esti- mated populations of the principal cities for each year since the last census. For the convenience of the reader, there is given in Appendix X a table of typhoid fever death-rates for the principal cities of the country for each year since 1898, compiled from the records of the Census Bureau and the Bureau of Labor. Comparison of these figures with those obtained from local sources do not always show an exact agreement, yet for the most part the figures may be taken as substantially correct. There is also a table giving the number of deaths in the larger cities of the country for a longer term of years, and still other tables for certain cities where the data are of especial interest. It is common to compare death-rates by the use of DISTRIBUTION OF TYPHOID FEVER. lOI NOaVTOdOd H3A3d QIOHdAX WOaS SHXVBQ dO UaakMON Fig. 4. Diagram Showing the Xumber of Typhoid Fever Deaths and the Corre- sponding Death-rates in St. Louis, Mo. I02 TYPHOID FEVER STATISTICS. diagrams. These are usually simple and self-explana- tory. A very convenient form, but one little used, is shown on page loi. Here the population, the number of deaths, and the death-rate are given on the same diagram. The first two are read from the horizontal lines, the reference numbers being on the left and right of the diagrams; the third is read by using the inclined lines upon which the reference figures are marked and noting the relation of the broken profile to these lines. CHAPTER VIL DISTRIBUTION OF TYPHOID FEVER. It will be of interest to consider briefly what the statis- tics show as to the distribution of typhoid fever among persons of different age, sex, race, occupation, etc., and the variations in the death-rates in different parts of the country. These topics cannot be discussed in detail, but the figures given are sufficient to show what are the main factors concerned in the distribution of this disease. Age Distribution. Typhoid fever is essentially a disease of youth and middle age. Deaths from it are comparatively rare in childhood and in old age. At the time of the last United States census, in 1900, it was found that more than one-third of the deaths from typhoid fever occurred among persons between 15 and 30 years of age; only 10 per cent among children under 5 years of age, and 10 per cent among persons over 50 years of age. These are average figures, and do not hold at all times for every community. Thus, in a city where the drinking-water of a school has been contaminated, or where there has been an epidemic caused by milk, the proportion of deaths may be especially high among the children. 103 104 TYPHOID FEVER. g< t^ invO M oo •* Tf O CT - O ro 00 OMO On 0 ro On r^ \0 ro U-) Tt ro vo O ■* O^ On Tl- t^ N t^ Ti- N N On w O On On 00 r^NO vo •& CO O W H M O ffi rD t^oo ro O On N lO M NO woo rf n 00 NO Tt w H M Tj- lO lo vn 't ^ ro fO « M M H H o O O o POOO On •* OnOO VO Tt -rj- rJ-00 ^ ^ ro fO O ^ M fO M C< lO N On H w 6 NO ro M odd ^^ o o o DISTRIBUTION OF TYPHOID FEVER. 105 It is generally taken for granted that the figures which show the age distribution of typhoid fever mean that people are more susceptible to the disease in middle life than in youth or old age. This, however, is not a true explanation. A better reason would be that per- sons in middle life are subjected to greater exposure. In the first place it should be noted that the figures in the seventh column of the table on page 104 show a too great disparity between persons of different age, for the reason that they take no account of the age distribution of the population. It is fairer, therefore, to consider the age distribution of typhoid fever on the basis of death- rates per 100,000 persons of the specified age, as is done in the last column. From this it will be seen that the death-rate in middle life is only about twice what it is in old age, and only about three times what it is in childhood. Age Groups. Under 5 years . 5 to 10 . . . . 10 to 15 . . . . 15 to 25 . . . . 25 to 35 . . . . 35 to 45 • • • • 45 and upwards Total . . . Number of Persons Attacked. 84 154 161 281 169 91 1008 Num- ber of Deaths. 5 13 32 26 17 24 119 Ratio of Percentage Number of Fatality. Cases to Deatlis. II. 81 38 42 25 30 07 12 35 8 3« 6 68 5 29 2 A study of the relative fatality of the disease at different ages also tends to show that the middle-age maximum as ordinarily stated is too much exaggerated. The per- I06 TYPHOID FEVER. centage of children who recover from the disease is far greater than in the case of older people. This is well shown by the figures on page 105 taken from Dr. Reece's report on the epidemic which occurred in Lincoln, England, in 1905. It will be seen that in this case the fatality of the disease increased almost directly with the age. Now, if an accurate and extended series of figures of this character could be obtained for a very large number of cases, and applied to an equally accurate and extended table showing the death-rates at different ages, it seems probable that the calculated rate per 100,000 of persons attacked at the different ages would be greatest in child- hood and decrease toward old age. Unfortunately, the data for an exact calculation are not now at hand. Fig. 5 shows diagrammatically some of these facts regarding age distribution. The lines for percent- age fatality and case-rate (rate of attack) are based on inadequate data and are to be regarded merely as illustrative. A further study of this subject would prove very instructive. The fact that so few children die of typhoid fever, then, does not show that the disease is not acquired at that age. There are doubtless many more "walking cases" among children than among adults. This helps to explain why children are such an important factor in the spread of the disease. Infants and very young children are in general less exposed to typhoid infection than persons in middle life; their diet is much simpler, and their environment is more limited. Yet typhoid fever is by no means DISTRIBUTION OF TYPHOID FEVER. 107 unknown among the very young, as the diagram shows, and physicians are coming to believe that it is more prevalent than has been generally supposed, many cases in the past having been set aside merely as infantile diarrhea, summer complaint, and other dis- COO 40 Fig. s. Diagram Illustrating the Age Distribution of Typhoid Fever. eases of an indefinite character. It is at the age when young men and women come to maturity, and when they are likely to change their environment in many ways, that there is a sudden increase in the typhoid death-rate. Between the ages of 20 and 25 it reaches its highest point. It then declines gradually until about the age of fifty, after which it remains nearly constant io8 TYPHOID FEVER. until the age of 75, when it drops again to the same rate as that of infancy. How much these changes are due to relative suscepti- bility at different ages, how much to acquired immunity and how much to environment, cannot be told. All of these factors are probably involved, but it is quite as likely that the maximum number of typhoid deaths at the age of about 25 years results from certain mathe- matical relations of the curves for age distribution of population, percentage fatality, and rate of attack than from any particular susceptibility at that age. A study of age distribution in certain milk epi- demics shows, as one would expect, that children are , Per Cent of Typhoid Cases at Specified Age. Age in Years. Water ville. (Epidemic Caused by Water,) Stamford. (Outbreak Caused by Milk.) •-^0 to 10 17 38 26 10 4 5 35 24 23 12 5 I 10 to 20 20 to 30 . 30 to 40 40 to 50 50 to 70 Total 100 100 more liable to be affected than older people. The Stamford outbreak is an extreme instance of this. For comparison, the age distribution there obtained is placed beside the age distribution obtained during the epidemic at Waterville, Maine, which was due to water. To a very great extent a person who has had typhoid DISTRIBUTION OF TYPHOID FEVER. 109 fever is immune from subsequent attacks, consequently in the case of older people a substantial percentage may be considered as non-susceptible; otherwise the death- rates at the older ages would be higher than are given in the table. Sex Distribution. Typhoid fever is more common among males than among females, as may be seen from the following figures, and from those given in the table of age distribution. Year. 1899 1890 1900 1890 1900 1900 1900 1900 1900 1900 1900 1900 Community. England and \\'ales .... U. S. Registration Area . . . Do U. S. Cities Do U. S. Cities (colored popula- lation) U. S. Cities: Under 15 years of age . . Age 15 to 24 Age 25 to 34 Age 35 to 44 Age 45 and over U. S. Registration Area (Rural Districts) : Under 15 years of age . . 15 to 24 25 to 34 35 to 44 45 and over Typhoid Fever Death-rate per 100,000. Males. Females. 23.2 16.8 52-4 27.4 57-4 38- 1 40.8 28.8 58.1 41-5 80.1 58.0 21.0 23.0 67.4 46.3 60.6 32-4 42.2 27.4 351 24-3 12.9 15-9 47.2 37-5 40.3 26.8 30.8 21.3 21.8 19.7 Percentage Excess of Death-rate Among Males. Per Cent. 38 37 36 41 40 40 45 87 54 44 -23 26 44 10 The death-rate is about 35 to 40 per cent higher among males than females, but this percentage varies at different no TYPHOID FEVER. ages. Girls acquire the disease at an earlier age than boys, so that in the case of children less than 15 years old the death-rate is greater, but only slightly greater, among females than among males. As age increases, this changes until at the age of 25 or 30 years the death-rate may be 50 to 80 per cent higher among males than among females. It seems reasonable to suppose that these differences are due to differences in exposure. In childhood the dif- ference between the environment of the two sexes is not material; but in middle life, when the activities of life are greatest, it may be supposed to be at its maximum; while in old age the environments again tend to become similar. Again, it is likely to be the case that in rural districts the environment of men and women in middle life is more nearly the same than in the case of cities; and the preceding table shows that it is in the cities that the greatest differences between the occurrence of typhoid fever in the two sexes are most marked. Racial Distribution. The data for determining the distribution of typhoid fever among the different races are altogether too imperfect to enable any general con- clusion to be drawn. The records of the last United States census show that the death-rate among the Scandinavian-bom population is high, and among the Russian-bom low, but such figures as these probably show the effects of environment more than the suscepti- bility of the races. Racial differences in diet may have some influence in the occurrence of the disease. There is some reason for thinking that a vegetable diet is less conducive to abnormal intestinal conditions than a meat diet, and it has been often remarked that the amount of DISTRIBUTIOX OF TYPHOID FEVER. Ill typhoid fever among Italian laborers living in close quarters under poor sanitary conditions is much less than would naturally be expected. The diet of Ameri- cans, as a nation, contains a larger percentage of meat than that of European nations. This idea, however, has little or no statistical basis, and must not be too seriously considered. As to the colored race in this country, environment seems to count for more than racial susceptibility. In the cities of the United States in 1900 the typhoid death-rate among the male white population was 34.8 per 100,000, and among the colored population, 68.8, - or about twice as much. The corresponding figures for females were 29.8 for the white population, and 70.0 for the colored. This difference is general throughout the southern states, where the colored population lives under much more unfavorable sanitary conditions than the whites. It is not so, however, among the colored people of the northern states, where the sanitar}' con- ditions of the two races are more nearly equal, — as, for instance, in the rural districts of the registration area, where in 1900 the typhoid death-rate among the white population was 25.5, and among the colored population 26.5 per 100,000. It is interesting to note in this connection that between 1890 and 1900 the typhoid fever death-rate among the white population of American cities decreased from 49.8 to 34.8 per 100,000, or 30 per cent, while the death- rate of the colored population decreased from 70.0 to 68.8, or less than 2 per cent. In the registration area, — New York and parts of New England, — the reduction 112 TYPHOID FEVER. in the death-rate among the colored population was fully as great, both in the cities and in the rural districts, as among the white population. In the cities outside the registration area the death-rate among the colored population increased during the decade from 67.2 to 72.7 per 100,000, although the death-rate among the white population decreased from 61.5 to 44.6 per 100,000. These facts all tend to show that environment rather than susceptibility is the controlling factor in the dis- tribution of typhoid fever among the races. Occupation Distribution. From the nature of the case, there are no general tendencies showing that typhoid fever is more closely associated with one occupation than another, except in so far as occupation is related to" sex, age, local conditions, etc. Yet a study of the distribution of typhoid cases by occupation in the case of any particular locality, or at the time of an epidemic, often gives a clew to the source of the disease. In Washington, D.C., during the summer of 1906 (June 11- Nov. i), the morbidity rate among school children was 500 per 100,000, and this included 27 per cent of all the cases; while among very young children the morbidity rate was 185; among housewives, 223; servants, 212; laborers, 259; clerks, 193, etc. A high morbidity rate among children suggests the probability of milk infec- tion. Rural and Urban Distribution. Contrary to what many people suppose, typhoid fever is more largely a rural disease than an urban disease, meaning by rural small communities in distinction from large commun- DISTRIBUTION OF TYPHOID FEVER. 113 ities. In cities, great epidemics occur at intervals; but in the small settlements of the country, the disease is present year after year, with here a victim and there a victim, and this inconspicuous but constant succession of cases counts far more than the spectacular epidemics which startle the readers of our daily papers. Dr. John S. Fulton, in 1903, presented to the American Medical Association some striking figures illustrating this rela- tion between urban and rural typhoid, which may be summarized as follows: Five states in which the urban population was more than 60% of the total Six states in which the urban population was be- tween 40% and 60% Seven states in which the urban population was between 30% and 40% Eight states in which the urban population was between 20% and 30% Twelve states in which the urban population was between 10% and 20% Twelve states in which the urban population was between o and 10% Average Per Cent of Rural Population, 30 49 67 75 87 95 Average Tjrphoid Fever Death-rate per 100,000. 42 38 46 62 67 Comparisons made between the city and country dis- tricts of the different states show the same relation, although in some years exceptions to the rule may be found. The figures given under climatic distribution sufficiently illustrate this point. The subject of rural typhoid fever needs far more 114 TYPHOID FEVER. attention than has ever been given to it, especially in the southern states. The smaller communities have not done their duty in stamping out the disease. It has been said that it is easier to save dollars than to save dimes; in the same way it is easier to reduce the typhoid fever death-rate of a great city by building filters and sewerage works than to give attention to the thousand foci of infection scattered through the villages of New England, the plantations of the South, and the lumber camps of the Northwest. Climatic Distribution. Typhoid fever is more abun- dant in warm climates than in cold climates; but to what extent this is due to the effect of temperature, and what to the nature of the environment, it is difficult to say. There is reason to believe that the latter is the more important factor. In the United States typhoid fever increases consider- ably from north to south. If the Atlantic coast and Gulf coast regions are followed from Maine to Texas, this increase is very evident, as the following census figures show: Region. Per Cent which the Typhoid Deaths in 1900 were of the Total Deaths. Rural. Cities. North Atlantic Coast Region Middle Atlantic Coast Region South Atlantic Coast Region Gulf Coast Region 1. 17 2-54 4-95 6.16 1.29 115 2.31 2.38 DISTRIBUTION OF TYPHOID FEVER. 115 It will be noticed that the increase in the rural districts is considerably greater than in the cities, — presumably because the general sanitary conditions, the quality of the drinking-water, etc., are better in the cities than in the country, especially in the South. If a line be taken down the hilly and mountainous regions in the general direction of the Appalachian Mountains, or down through the middle West, the same distribution will be seen. Region. Per Cent which the Typhoid Deaths in 1900 were of the TotaJ Deaths. Rural. Cities. Northern Hills and Plateaus Central Appalachian 1. 81 2-57 6-45 7.61 215 3-59 7.06 I. 81 1.92 4. 16 3.10 3-35 3-87 Southern Appalachian Southern Interior Plateaus Heavily Timbered Region of the North- west ■ Prairie Region Southwest Central There are some exceptions to this regular increase of typhoid fever southward. For example, in 1900 the death-rate was higher in certain parts of the state of Washington than in Florida. The city of Winnipeg, Manitoba, has a high death-rate, and the rates in many other parts of Canada are high. Geographical Distribution. Typhoid fever is much more abundant in the United States than in most for- ii6 TYPHOID FEVER. eign countries. This is shown by the following data, taken from the Mortality Statistics of the Bureau of the Census for 1905. Date. 1900 1900 1900-1904 1902 1900-1904 1902 Country. United States United States, Registration Area . United States, Registration Area . Norway Switzerland Germany Holland Sweden Scotland England and Wales Ireland Belgium Hungary Italy Spain Typhoid Death- rate per 100,000. 47-3 33-8 33-7 6.2 6.5 8.5 8.6 12.2 12. 7 12.9 14. 2 20.2 28.3 37-8 45-8 The following figures show the typhoid death-rates in various European cities about the year 1903: — Berlin, Germany . . Vienna, Austria . . . Hague, Holland . . . Berne, Switzerland . . Copenhagen, Denmark London, England . . Brussels, Belgium . . Paris, France .... Lisbon, Portugal . . Madrid, Spain . . . St. Petersburg, Russia Typhoid Death- rate per 100,000. 5-0 5 I 5 I 7 13 3 14 4 17 2 21 7 29 4 50 80 7 DISTRIBUTION OF TYPHOID FEVER. I17 The question naturally arises, "Why is the typhoid death-rate so much lower in Western Europe than in the United States?" There are many reasons for it. Surface waters used without filtration are less frequent abroad. In Germany, for instance, the filtration of surface waters is required by law, and rigid restrictions are in force as to the efficiency necessary to be obtained by the filters. Probably, too, less water is used there as a beverage. In Europe, milk is more often boiled before using, and oysters are not as much eaten as with us. Better water and safer milk having materially reduced the disease, the secondary causes, such as contagion and carriage by flies, decrease as a matter of course. It is possible that differences in ' the classification of disease and incompleteness of records may influence the figures given above, but they do not materially affect the com- parison. A generation ago the waters of Northern Europe were far less safe than they are to-day, and there was then good reason for travelers refraining from drinking the public supplies, just as there is to-day in Southern Europe and in the Orient. The movement for obtaining pure water-supplies is, however, world-wide, and at the pres- ent time the average water-supphes in England and in Northern Europe are quite as safe to drink as the average supplies of America. In Japan the water-supplies of most of the large cities have been subjected to filtration for a number of years. It is said that typhoid fever is an infrequent disease in the Philippine Islands, and that it was practically ii8 TYPHOID FEVER. unknown before the time of the American occupation, thus illustrating Professor Sedgwick's statement that typhoid fever is a disease of civilization. Since then, to quote from a report to the Philippine Commission, "the disease has made its appearance from time to time in various parts of the islands, especially at places at which troops were stationed. " At Baguio it was said that the near approach of the new road, with its swarms of workmen and its attendant swarms of flies, led to the temporary introduction of several diseases which had not been previously present. There was a slight epidemic of typhoid fever, which was spread by flies, but which was promptly controlled with a total of only seven cases. In the city of Manila itself typhoid fever has been by ho means absent, as the following figures show. During the year ending Sept. i, 1905, there were 122 deaths, and during the following year, 45. During the year ending June 30, 1905, there were 23 cases and 5 deaths among the United States troops. MANILA, PHILIPPINE ISLANDS, SEPT. i, 1904, TO SEPT. i, 1905. Race. Popula- tion Deaths from All Death-rate per 1000. All Causes. Typhoid Fever Typhoid Death-rate (1903). Causes. Deaths. per 100,000. Americans . . . 4,389 39 8.88 I 25.6 Philippines . . 189,782 8,453 44 54 no 58.2 Spaniards . . . 2,528 51 20 17 } ^ J 160.5 Other Europeans 1,117 14 12 53 Chinese .... 21,230 343 16 15 5 23.6 All others . . . 26 29 05 Total . . . 219,941 8,926 40 58 122 55-7 DISTRIBUTION OF TYPHOID FEVER. 119 Apparently these figures overstate the amount of typhoid present, for recent studies carried on in the government laboratory have shown that a large pro- portion of the so-called typhoid fever cases fail to respond to the Widal test. In one of the surgeon's reports to the Commission it is stated that "with the rapid increase in the use of milk in the city of Manila and because of the thickly populated watershed from which the city obtains its water-supply, it is rather probable that Manila is in considerable danger of becoming thoroughly infected with typhoid fever unless the greatest precautions are taken to prevent its gaining a foothold. " During 1 898-1 902 the average death-rate for typhoid fever in various cities of the West Indies and South America were as follows : — Rate per 100,000. Havana, Cuba . . . San Jose, Costa Rica Santiago de Chile . . Rio Janeiro Buenos Aires . . . . 39-3 74-9 48.3 15-9 22.0 Geological Distribution. Studies of the distribution of typhoid fever along east and west lines of the United States do not reveal any changes that can be attributed to altitude, to rainfall, or to any geographical or climatic influence. There does seem to be, however, some coinci- dence of high typhoid fever rates and the presence of a clayey soil. Within the area of the glacial drift, and 120 TYPHOID FEVER. along the eastern sea-coast, the disease is somewhat less abundant than in the alluvial regions of the southern and central states. This area is so largely coincident with the presence of the negro race, however, that no sweeping generalization can be made; yet it is evident that with an impervious soil, the opportunities for surface contamination of streams, springs, and wells are greater than in a sandy region where the natural purification of the soil plays a larger part. The soil factor must not be given too much weight, however; for it is to be remembered that in England, where the soil is heavy, the typhoid rate is comparatively low. The opportunities for the pollution of wells are some- what increased in a limestone region, where cracks and crevices in the rocks may exist, but this factor does not manifest itself in looking at the distribution of the disease over large areas. Hydrographic Distribution. Typhoid fever is often abundant along the courses of streams, especially where the streams are used both for the disposal of sewage and for the supply of drinking-water to the cities along the shores. Examples of this condition along the Penobscot River, the Merrimac, the Hudson, and other streams are referred to elsewhere. It is said that all through the Potomac and Shenan- doah valleys typhoid fever has been constantly prevalent ever since the Civil War, and no doubt much of the typhoid fever in the South to-day represents a legacy left by the armies engaged in that conflict. The disease is sometimes abundant at sea beaches and along the shores of bodies of water into which sewage is DISTRIBUTION OF TYPHOID FEVER. 121 discharged. Epidemics of some magnitude have resulted from bathing in infected waters; and it has been sug- gested that along water-fronts where sewage is discharged under the wharves, flies may act as carriers of the bacilli Fig. 7. Diagram Showing the Seasonal Distribution of Typhoid Fever in the United States. (From the U. S. Census Bureau of 1900.) from the deposits left by the tides to persons dwelling or working near the shores. Mr. D. D. Jackson in a report to the Merchants' Association has recently empha- sized the importance of this factor in New York City. 122 TYPHOID FEVER. Fig. 8. Diagram Showing the Seasonal Distribution of Typhoid Fever in Certain Cities of the United States. DISTRIBUTION OF TYPHOID FEVER. 123 Seasonal Distribution. In the United States the normal seasonal distribution of typhoid fever is shown by Fig. 7. June is the month when the disease is usually least abundant. During the summer, it increases gradually until it attains a maximum in October, then 180 160 O140 °130 Eloo 40 20 / _^ / / '^c P, / \ / / F?°. ^^ N, / s J \ \ J / ^ ' ' y V y AF ■ER / ^^ V "^ *^-^ ^ TION ^ "^ "^ 2 CD Fig. 9. Diagram Showing the Seasonal Distribution of Typhoid Fever in Albany, N. Y., before and after the Fihration of the Public Water-Supply. it gradually decreases, though with some slight fluctua- tions during the winter and spring months. This normal curve holds approximately for most rural sections and for cities which are provided with good, or fairly good, water-supplies. Thus the sea- sonal distribution of typhoid fever in New York City follows the normal curve. In cities which have polluted water-supplies there is likely to be a more irregular occurrence of the disease, with maxima, or sub-maxima, 124 TYPHOID FEVER. in the colder part of the year. The occurrence of an epidemic is likely to abnormally affect the shape of the 80 "] — — — — "1 1 — — 1 ~ 20 -15 -10 -5 20 ■15 -10 -5 20 -15 ■10 -5 70 .-i ^,- ""'V v ^ VN / > 60 Q / \ ^ / / s \ $l{ I / y\ / / \ \ 50 "1 "/ \ : / / \ 'v fl \ 1 J r \ \ 40 1 1 * / ^;n \ / / \ \ I ^ — " r\ r- N ti.. ^^ i-' ^ f- 1- zq: 30, / p OS ro N V. ^.* r' ^_Ew ^ 'O >v 'N M^ -^ -1-5 88 ■^ 1 T^ 20 qUJ UJH ■5 70 J \ XO 1 \ 560 ^ ... , t ^ N V / / Su • \ I OS a. =50 tr ui40 S Ui H30 t — . / \ > s , i \ k \ Q-_i f / KN s / 1 \ k _. -' 1 '^^ ^ / \ Ov "^ ■— — ' '-S -i. ' N ^ LUm ■~ -Bf 1 1 "l^/1 nR F ^\-y-r 20 70 ZUJ \ 1 IT 60 .._^ *> ^^ _,« '-•'■' -- .— "> .^ \ ,^ V \^ Q. 50 _^ — -' '' \ s \ ,' j \ / ^ \ s ^> ^.. -' I 40 - - / \ ^ \, J ^ 1 " — 30 SA N I ■RANGIS CO SA NT lAGO D = GH LE 1888-1897 1886 -1^95 20 z < 1 1 1 CO ■u u. a. < •z. a. a < > < z -3 > -3 < Q. UJ > z d UJ z < z < d UJ u. a. < q: a. < ^ Z UJ z > -i < UJ 8 > z d UJ z < Fig. 10. Diagram Showing the Relation between Atmospheric Temperature and Seasonal Distribution of Typhoid Fever. (After Sedgwick and Winslow.) DISTRIBUTION OF TYPHOID FEVER. 125 curve. The diagram on page 122 shows the seasonal distribution of the disease in cities where the pubHc water-supply is of fairly good sanitary quality, and in cities where it is polluted. It will be seen from these curves that the character of the water-suppHes is best indicated by the typhoid fever records during the winter and spring months. Of the three largest cities, New York has the best water, Chicago next, and Philadelphia next; and this is the order of the typhoid curves during the first half of the year. Not so, during the summer and autumn. Here the differences between the three are much less, and the rate at Chicago is highest. There • is reason to believe that during this season of the year the effect of the quality of the milk-supply, and the influences of flies and general sanitation, exert a preponderating influence on the height of the curve. Even more striking, perhaps, is the change in the seasonal distribution of typhoid fever after a city has changed its source of water-supply from bad to good, or has improved the character of its supply by filtration. Albany is a good illustration of this. Many theories have been advanced to account for the greater general prevalence of typhoid fever in the autumn than at other seasons of the year. That it is in some way related to temperature can scarcely be questioned. Sedgwick and Winslow have illustrated this by a beautiful series of diagrams for various cities in different parts of the world. Some of these are reproduced in Fig. 10. The way in which the typhoid curves follow the 126 TYPHOID FEVER. temperature curves is very striking. In order to better show the correspondence, the typhoid fever curves have been set back two months, — thus allowing for the period elapsing between the date of infection and the date of death. Sedgwick and Winslow explain this correspondence between temperature and typhoid by the general unfavorable influence which cold exerts on the persistence of the typhoid bacillus outside the body. It is held that during warm weather trans- mission by contact is more frequent, and infection by other methods rendered more likely by reason of an increased longevity of the bacilli. Other reasons for the greater prevalence of typhoid fever in warm weather will naturally suggest themselves. Flies and other insects are more abundant and more active in summer; bacteria multiply faster in milk; fruits, berries, and uncooked foods are more commonly used; more water is drunk, and ice is put into it; wells are lower, and the danger of contamination is thereby in- creased; traveling is more common, and opportuni- ties for transmission by contagion are thus greater. The consumption of oysters, on the other hand, is less in summer than in winter. The idea has been recently suggested by a number of sanitarians, that the greater prevalence of diarrheal diseases of a mild type and of various intestinal disorders during the hot weather, due to bad milk, unripe fruit, etc., may act as exciting causes, and, by reducing a per- son's vitality and by irritating the intestinal walls, may increase the chance of infection among those who are exposed. The somewhat greater proportion DISTRIBUTION OF TYPHOID FEVER. 127 of typhoid cases among young people during the sum mer than during the winter lends countenance to this theory, as well as the fact that typhoid epidemics are quite frequently preceded or accompanied by an unusual amount of diarrhea. On the other hand, the testimony of the commission that studied the occurrence of typhoid fever in our army during the Spanish War is to the contrary. Vacation Typhoid. The autumnal increase of typhoid fever in cities is sometimes referred to as "vacation typhoid," — the idea being that it is due to patients returning sick from the country. This theory is based on the fact that typhoid fever is at present chiefly a rural disease, and so far as this goes it is correct. But the notion of "vacation typhoid" has been very much overworked, and, as a matter of fact, it does not to any very material extent account for the summer and autumnal increase of typhoid fever in the large cities. In Washington it was estimated that during the summer and autumn of 1906, 85 per cent of the cases were contracted within the city, and studies of imported cases in other cities have given similar figures. Cities which have polluted water-supplies generally show this fact by an unusual prevalence of typhoid fever at other seasons than the summer and autumn, and most of the severe epidemics due to infected water have occurred during the late autumn, winter, or spring; but in the cases of cities supplied with water from impounding reservoirs located on watersheds more or less polluted, opportunities for the transmission of infection may be increased during the late summer. The reservoirs are then likely to be drawn down, so that 128 TYPHOID FEVER. a hard rain may carry infection rapidly through them to the city. It seems to be a fact that in such cities the amount of typhoid fever is greater during years of dry summers. Chronological Distribution. Typhoid fever is grad- ually becoming less frequent as a cause of death. This is due partly to a reduction in fatality through better medical treatment, but is chiefly due to a reduction of infection by reason of better water-supplies and a more logical sanitary regime based on the germ theory of disease. The chronological distribution of the disease will be repeatedly referred to in other places, but at this point it may be sufficiently illustrated by the following average figures for twelve states, including all the New England states and New York and New Jersey, Mary- land, California, Minnesota, and Michigan. Year. Average Typhoid Fever Death-rate per 100,000. Year. Average Typhoid Fever Death-rate per 100,000. 1880 1885 1890 55 46 36 189s 1900 1905 28 23 21 A generation ago, about one person in every five or six in the United States was bound to have the typhoid fever at some time in his life, and one person in every fifteen or twenty died in an uphill fight against this insidious enemy. To-day, under the average conditions in the United States, the chance of having the typhoid fever at some time between the cradle and the grave is only about one in ten. What is the future to be ? The DISTRIBUTION OF TYPHOID FEVER. 129 prospect is bright. The indications are that the disease is soon to become much less prevalent than it is to-day. In another generation the death-rate ought not to be over a third or a quarter of what it nov^ is, — and who can say that the disease will not be all but obliterated, just as smallpox has almost vanished from our midst ? Typhoid fever has been decreasing in foreign countries. The following figures show this decrease for England and Wales: Year. Typhoid Death-rate Year Typhoid Death-rate per 100,000. per 100,000. 1870 1875 1880 38 37 26 1890 1895 1900 17 17 17 1885 17 1905 9 Effect of Spanish War. The Spanish War caused something of a set-back to the gradual decrease of typhoid fever in America. The enormous number of cases that TABLE SHOWING THE TYPHOID FEVER DEATH-RATE FOR NINE STATES. Year. Death-rate per 100,000. Year. Death-rate per 100,000. 1895 1896 1898 30-5 27.7 21-5 25.2 1899 1900 1901 1902 235 27.9 25.2 20. 2 occurred in the military camps caused the disease to be quite generally scattered through the country, and these I30 TYPHOID FEVER. new foci gave rise to various outbreaks, with the resuk that the general death-rate temporarily increased. Men- tion is made elsewhere of the fact that in New York City and in Brooklyn the typhoid fever rate in 1898 increased Fig. II. on account of the soldiers returning from the war. A simi- lar increase occurred in many other cities ; for instance, in Portland, Maine, the death-rate rose from 24 to 76 per 100,000. Statistics collected for nine states showed a decided increase during the same year. For instance, the DISTRIBUTION OF TYPHOID FEVER. 13 1 average death-rate had been 21.5 in 1897, but rose to 25.2 in 1898, falling again to 23.5 in 1899. The amount of typhoid fever in 1899 was unexpectedly low, but in 1900 it again rose, and was even higher than in 1898. Whether or not this increase was due to the spread of infectious matter by the soldiers, cannot be said. It may have been; but if this were so the question comes. Why was not the rate high in 1899 ? Since 1900 there has been a general reduction in the prevalence of typhoid fever, but 1904 was another bad year. During this year the great epidemics occurred in Ithaca, Butler, and else- where. There are no data for explaining these waves of typhoid which sometimes sweep over the country. Distribution by Causes. To state, with any degree of exactness, the proportion of cases of typhoid fever due to different causes, is absolutely impossible from such data as now exist, and yet this is a question often asked. Even if the data were at hand, it could be answered only in a very general way, for the relative effects of different causes are not the same at all times and in all places. From a study of the statistics, however, a rough approximation can be made of the more important causes, though the results are hardly more valuable than a shrewd guess. When a contaminated public water-supply is suddenly improved in quality by the installation of a filter plant, there is nearly always a decided fall in the typhoid fever death-rate. Cities which have pure water have a gen- erally lower death-rate than those which have an impure supply. These differences may serve as a rough measure of the amount of typhoid fever due to impure public 132 TYPHOID FEVER. water-supplies. The average typhoid death-rate in American cities is about 35 per 100,000. The cities in the north which have safe water-suppHes have lower rates, — usually as low as 20, and frequently as low as 15 or even 10. Taking the country over, perhaps 20 may be taken as an average figure. The difference between 20 and 35 may be considered, therefore, as being due to infected public water-supplies. Of the "residual typhoid," the most potent causes are probably infected milk, and direct infection by contagion, by flies, etc. Oysters, vegetables, and other foods really play a very insignificant part in the general typhoid death-rate. A number of years ago infected water probably caused more typhoid fever than all the other causes combined. That is not the case to-day when the country as a whole is considered, although it is still the most important cause, and m some cities, as in Pittsburgh and Philadelphia, it still overshadows all other causes. The long-continued struggle for pure water is bearing fruit, and to-day in many American cities, and even in entire states, where the public water-supplies are well guarded from pollution, infection by water has come to be a secondary cause of the disease. In a general sort of way it may be said that in the cities of the United States, at the present time, about 40 per cent of the typhoid fever is due to water, 25 per cent to milk, 30 per cent to ordinary contagion (including fly transmission), and only about 5 per cent to all other causes. In cities supplied with pure well water or fil- tered water, the effect of water is negligible; where the water is impure, it is still the most important cause of the DISTRIBUTIOX OF TYPHOID FEVER. 1 33 disease. In the case of rural districts there are no data to show the relative eflFect of infected wells, infected milk, and direct infection, but, in all probability, the "honors are about even." ^^^lile the care of water-supplies cannot be in any degree relaxed, efforts for further reducing the disease must be directed to causes other than water. It is the realization of this fact that explains in part the present strenuous struggle which is being made in our large cities to improve the milk-supply. In many ways the milk problem is more difficult than the water problem, as the sources of supply are so numerous, the commodity is such a delicate one to handle, and its distribution so complicated. When one considers the difl&culties of the milk situation, and the large percentage of the disease due to personal contact, that is to contagion, the wisdom of stamping out the disease at the bedside must be evident to every one. CHAPTER VIII. TYPHOID FEVER EPIDEMICS. From time to time, in one place or another, typhoid fever suddenly increases until it is said to be epidemic. If the increase is confined to a small portion of the com- munity and is more or less localized, it is usually termed a "local outbreak," or a "sporadic outbreak;" but if it is widely spread and can be attributed to some general cause, as the water-supply, or the supply of some large milk dealer, it may be fairly termed an epidemic. There is no necessity, however, for drawing a fine distinction between the two, as the difference is merely one of mag- nitude; but it will often be wise to use the term "out- break " rather than " epidemic," in order to prevent undue excitement and avoid the opprobrium attached to the larger word. A study of typhoid fever epidemics forms a necessary part of the history of our subject, and from them many lessons in sanitary science may be learned. It will be instructive to consider in some detail a few of the more important epidemics of typhoid fever which have been traced to different causes. Those chosen for illustration have been selected either by reason of their magnitude, or because they illustrate some new or interesting case of infection. The data given are taken from well-known •34 TYPHOID FEVER EPIDEMICS. 1 35 authorities, and references to more detailed accounts are given in the appendix. Classification of Epidemics. The epidemics and out- brealis of typhoid fever to be described may be classified according to their suspected causes as follows : I. Epidemics due to infected water: 1. Epidemics caused by the sudden infection of a water- supply popularly supposed to be of good quality. PhTnouth, Pa. Xew Haven, Conn. Ithaca, X. JA Scranton, Pa. \ 2. Epidemics caused by water constantly subject to con- tamination. a. River water. Lowell and Lawrence, Mass. Watenille and Augusta, ^Maine. Pittsburgh and Allegheny, Pa. v/'6. Lake water. Chicago, ni. Cleveland, Ohio. Burlington, Vt. 3. Epidemics caused by water accidentally infected. Butler, Pa". Lowell, Mass. Millinocket, Maine. Baraboo, Wis. Steamer "Northwest." 4. Epidemics and outbreaks caused by infected ground water. Lausen, S\^"itzerland. Basingstoke, England. Newport, R.I. Auxerre, France. Trenton, N.J. !Mount Savage, Md. //. Epidemics and outbreaks due to contagion, flies, and general uncleanliness : New Haven County Jail. Winnipeg, Manitoba. United States ^Slilitar}- Camps during the Spanish War. 136 TYPHOID FEVER. III. Outbreaks due to injected milk: Somerville, Mass. Springfield, Mass. Stamford, Conn. Marlborougli, Mass. Waterbury, Conn. Montclair, N.J. IV. Outbreaks due to infected oysters and other shell-fish: Wesleyan University, Middletown, Conn. Winchester-Southampton, England. Lawrence, Long Island. V. Outbreaks due to infected fruit and vegetables: Springfield (1905). VI. Outbreaks due to infected ice: Ogdensburg, N.Y. VII. Outbreaks due to other causes, such as cream, ice-cream, various foods: No specific examples described. Epidemics Due to Injected Water. ■ The Pljmiouth Epidemic. Among the typhoid fever epidemics which have occurred in America that at Plymouth, Pa., deserves first mention, partly for the reason that it was one of the first large epidemics where the cause was definitely ascertained, and partly because of the influence which the lessons taught by it have had on sanitary science in this country. The epidemic occurred in the spring of 1885. Plym- outh at that time was a mining town of about 8000 inhabitants. It had a public water-supply derived from a stream which drained an almost uninhabited water- shed, and the water was stored in a series of four small reservoirs. The highest of these reservoirs had a capacity of 5,000,000 gallons; the next, 3,000,000; the next, 1,700,000; and the lowest, nearest the city and TYPHOID FEVER EPIDEMICS. 1 37 used as a distributing reservoir, 300,000 gallons. This water-supply, though apparently satisfactory in quality, was not sufficient at all times for the needs of the city, and occasionally it was necessary to supplement it by pumping from the Susquehanna River. Well waters were also used by some of the inhabitants. As it turned out, neither the well water nor the polluted Susque- hanna water played any part in the epidemic, which, through the efforts of Dr. L. H. Taylor of Wilkesbarre, and others, was found to have been caused by the "pure mountain stream" supply of the Plymouth Water Company. It is unnecessary to follow here all the steps by which the epidemic was traced to its origin; it will be simpler to recite the pertinent events chronologically, and this will also indicate more clearly the relation between cause and effect. In an open clearing near the banks of the stream and just below the upper reservoir, there existed one of the few houses on the watershed. The man who occupied this house went to Philadelphia on Dec. 24, 1884, and on Jan. 2, 1885, returned home ill with typhoid fever. It was a severe case. The patient was in bed for many weeks. By the first of March he was convalescent, but a relapse occurred, and it was the middle of April before the physician's visits were discontinued. "During the course of his illness, his night dejecta were thrown without disinfection upon the snow and frozen ground, toward and within a few feet of the edge of the high bank which sloped precipitously down to the stream supplying the town with water." "The dejecta passed during the 138 TYPHOID FEVER. day were emptied into a privy a little farther back, the contents of which laid almost upon the surface of the ground, so that at the first thaw or rain they too would pass down the sloping bank and into the stream." Until the latter part of March the ground remained frozen and covered with snow, and under these con- ditions it is improbable that the dejecta reached the water of the stream. But during the last week in March there was a thaw, the air temperature increased rapidly until, on April 4, the maximum was 70 degrees. During these few days of warm weather the accumulated dejecta of many weeks probably found their way into the stream which supplied the town with water. On the evening of March 26, the superintendent of the water company visited the reservoirs and found that the two lower ones were almost empty, while the one just below the house where the typhoid patient lived, was filling rapidly. He found, however, that the short pipe which allowed the water to discharge from the bottom of this reservoir into the stream leading to the reservoir below it was frozen, and he caused a fire to be built to melt the ice in the pipe. This done, the water flowed from the bottom of this reservoir down through the two reservoirs below it, and thence into the town, where in all probability it first arrived some time between March 28 and April 4 or 5, — that is, from two days to a week after it was let down from the third reservoir. The first case of typhoid fever in the town occurred on April 9, and from this time on the disease spread rapidly. During the week beginning April 12, from TYPHOID FEVER EPIDEMICS. 1 39 50 to 100 new cases appeared daily, and it is said that on one day 200 new cases were reported. All classes of people were attacked in all parts of the town, until, before the epidemic ceased, out of the 8000 inhabitants, 1104 contracted the disease, and 114 died. This epidemic, as Dr. Taylor said in his report, "was one of the most remarkable ones in the history of typhoid fever, and taught important lessons, though at a fearful cost. One is, that in any case of typhoid fever, no matter how mild, or how far removed from the haunts of men, the greatest possible care should be exercised in thoroughly disinfecting the poisonous stools. The origin of all this sorrow and desolation occurred miles away on the mountain side, far removed from the populous town, and in a solitary house situated upon the banks of a swift-running stream. The attending physician did not know that this stream supplied the reservoirs with drinking-water. Here, if at any place, it might seem excusable to take less than ordinary precautions; but the sequel shows that in every case the most rigid attention to detail in destroying these poison- ous germs should be enjoined upon nurses and others in charge of typhoid fever patients, while the history of this epidemic will but add another to the list of such histories which should serve to impress medical men, at least, with the great necessity for perfect cleanli- ness, — a lesson which mankind at large is slow to learn." The epidemic is interesting to bacteriologists from the fact that it throws some light upon the ability of the typhoid bacillus to survive the apparently unfavor- 140 TYPHOID FEVER. able conditions of winter. Some of the bacilli at least must have lived and retained their virulence in the frozen fecal matter for many weeks. The New Haven Epidemic. In the early spring of 1901 an epidemic of typhoid fever occurred in New Haven, Conn,, which was similar in many ways to that which occurred in Plymouth in 1885. During April, May, and June, 514 cases occurred, resulting in 73 deaths. The epidemic began about the middle of March, and increased as shown by the following figures : Period. Number of Cases. Period. Number of Cases. March 20-26, 1901 . . March 27-31, 1901 . . April 1-5, 1901 . . . April 6-10, 1901 . . . 36 99 195 58 April 11-15, 1901 . . April 16-20, 1901 . . April 21-25, 1901 . . April 26-30, 1901 . . . 38 9 3 3 Professor Herbert E. Smith made a careful study of this epidemic, and found that it was unquestionably due to an infection of one of their sources of public water- supply. The water-supply of New Haven was drawn from five distinct systems. It was all surface water, and was used without filtration. One of these sources was known as the Dawson supply. Dawson Lake was a storage reservoir located on West River in Woodbridge, five miles from the city. It had an area of 60 acres, and a capacity of 300,000,000 gallons. The watershed tributary to the lake had an area of 13.6 square miles, upon which there was no direct sewage pollution. TYPHOID FEVER EPIDEMICS. 14I while the rural population amounted to only 25 per square mile. A mile and a half above the Dawson dam a small stream flowed into the river, and about half a mile up this stream there was a farmhouse situated at an elevation of about 180 feet above the water in the lake. During January and February, 1901, several cases of typhoid fever occurred in this house. The excreta were thrown into a shallow privy vault without disinfection (for the reason that typhoid fever was not at first recog- nized), where they must have accumulated and remained more or less frozen for six weeks or more. This privy was 325 feet from the brook and 40 feet above it. Dur- ing February and the first part of March, the weather was steadily cold; but on March 10 and 11 there was a heavy rainfall, during which the precipitation was 2.46 inches. The flow was so large that in spite of the inter- vention of the storage reservoir, the water in the city was in a turbid condition on the afternoon of March 11, As the typhoid fever outbreak began about ten days later, there seems to be little doubt that the infection took place at this time. Professor Smith found that 96 per cent of the cases that occurred were in the district supplied with water from Dawson Lake. In the course of his studies he made some interesting comparisons of the distribution of the cases by ages, which were in striking contrast to those found in the Stamford epidemic of 1895, which was attributed to infected milk. The following table shows these percentages. 142 TYPHOID FEVER. PER CENTS WHICH THE NUMBERS OF CASES AT CERTAIN AGES WERE OF THE TOTAL NUMBER OF CASES. Ages. 0-5- 6-15. 16-30. 31-45. Over 45. Stamford Epidemic .... New Haven Epidemic . . % 16.95 8.10 % 48.19 36-73 % 32.90 49.66 % 14.76 10-43 % 4-15 3-i8 The Ithaca Epidemic. In ihe winter of 1903, Ithaca, N.Y., the seat of Cornell University, was visited by a severe epidemic, in the course of which 1350 cases of typhoid fever occurred, in a population of about 13,156. More than 500 homes were visited, and there were 82 deaths. The epidemic covered a period of about three months, and extended from about the nth of January, 1903, to the first of April, although for several months before the epidemic began, typhoid fever had been unduly prevalent. This epidemic was carefully studied by Dr. George A. Soper, in the interest of the New York State Department of Health. The original case, or cases, which gave rise to the epidemic were not ascertained, but that the disease was due to the public water-supply was made certain by the investigations carried on. Ithaca had at that time three separate sources of water-supply, two of these being owned by the Ithaca Water Company, and the third by Cornell University. The latter supply, however, probably had little or nothing to do with the epidemic. Of the other two supplies, the larger one was derived from Six-mile Creek, which had a drainage area of about 46 square miles. The water was taken from a TYPHOID FEVER EPIDEMICS. 1 43 small reservoir formed by damming this stream below the intake crib, and pumped into a reservoir and stand- pipe, from whence it flowed by gravity to the consumers. The second supply was taken from Buttermilk Creek, a stream which drained about 12 square miles. The conditions on the two streams were similar. On both the run-off was rapid, and the flow was subject to violent fluctuations. The river beds were deeply eroded through the soil, and at times of flood the water carried a large amount of silt in suspension. Both streams were considerably polluted. On the drainage area of Six-mile Creek there dwelt a population of more than 2000, about forty per cent of which lived in vil- lages bordering on the creek. The nearest of these villages to the waterworks was Brookton, five miles above the intake. The inspection of the watershed showed that there were numerous sources of contami- nation, and that even in the city of Ithaca, a few rods above the intake of the waterworks, there were no less than seventeen privies located on the precipitous banks of the creek. It is known, furthermore, that during the year previous to the epidemic, there had been at least six cases of typhoid fever on the watershed. At the time of the epidemic, a new dam was being constructed on Six-mile Creek, a short distance above the water works intake. One theory advanced was that the excreta from a possible case of typhoid fever among these laborers may have caused the epidemic. No proof of the existence of such a case, however, was found. Another possible source was a gang of laborers working 144 TYPHOID FEVER. near the stream three miles above the intake, where one of the party was known to have had the disease. Whether some one of these cases or some unknown case was the active agent in causing the epidemic was not determined, but that the water was in some way infected cannot be doubted. As in the cases of Plymouth and New Haven, the typhoid epidemic in Ithaca followed a flood in the river. During the month of December, 1902, the precipitation had been unusually heavy. General rains occurred be- tween the 19th and 2 2d, and there were heavy rainfalls on the 13th, i6th, and 21st. The epidemic began about the nth of January, and gradually increased in severity during the rest of the month. On some days more than 30 new cases were reported. The following figures show the progress of the epidemic by weeks: New Cases New Cases Week Ending — Reported by Week Ending — Reported by the Physicians.' the Physicians.' January 17, 1902 21 February 28, 1902 59 January 24, 1902 54 March 7, 1902 31 January 31, 1902 105 March 14, 1902 18 February 7, 1902 170 March 21, 1902 3 February 14, 1902 137 March 28, 1902 3 February 21, 1902 102 ' The actual number of cases was larger than these figures would indicate, as not all were reported. This epidemic occasioned an unusual amount of interest by reason of the fact that the town included about 3000 students in Cornell University. Hundreds of TYPHOID FEVER EPIDEMICS. 145 the students left town, some of them ill with the disease. Some of them probably scattered the disease elsewhere. The effect of such an epidemic is far-reaching. One episode of the epidemic is worthy of special mention, namely^ a secondary outbreak which resulted from the infection of a well. This well had become popular among the residents of a certain district at the time when the public supply came to be distrusted, and its good quality was taken for granted. But the wife of the owner was taken sick with typhoid fever during the epidemic, and her dejecta passed without disinfection through the water-closet, and into a drain-pipe which ran within three or four feet of the well. The joints of the drain -pipe were insecure; and the well water, which had probably been for some time grossly contaminated, finally became infected. As a result, about fifty cases of typhoid fever and five deaths were traced to people who used this well water. The Scranton Epidemic. Scranton is a coal-mining and manufacturing city of about 119,000 inhabitants in the eastern part of Pennsylvania. Until December, 1906, it had had a fairly satisfactory typhoid fever record. The water-supply of the city was taken chiefly from impounding reservoirs on Roaring Brook, south of the city, and delivered to the city by gravity. The main storage basin, known as Elmhurst Reservoir, had a capacity of about 1400 million gallons, or nearly 50 days' supply. From it the water flowed through an open stream several miles long, to what is known as No. 7 Reservoir, the starting-point of the city mains. No. 7 Reservoir had a capacity of about 100,000,000 gallons. 146 TYPHOID FEVER. and the distance from inlet to outlet was only about 2000 feet. Provision was made for carrying the water direct from the Elmhurst Reservoir to the city, if desired, without passing through No. 7 Reservoir, and the pipes were so arranged that any excess of water in Roaring Brook could be diverted and stored in Scranton Lake, on a neighboring watershed, for use during the summer. The Roaring Brook supply in 1906 furnished the greater part of the 30 million gallons per day used by the city. The other supplies, also impounded surface waters, were not concerned in the epidemic, and need not be considered. Until the last of October, 1906, the Roaring Brook water was delivered to the city by allowing it to flow through the No. 7 Reservoir, but at that time this reservoir was cut off, and the water was furnished direct from Elmhurst, being taken from a point near the bottom. Although thought to be of good quality, the water- supply was open to contamination at various points. Roaring Brook flowed through the center of Moscow, a village of about eight hundred people, only a mile above Elmhurst Reservoir, and the borough of Elmhurst bordered the brook below the reservoir. The main lines of the Delaware, Lackawanna & Western Railroad crossed and recrossed the brook, thus offering oppor- tunities for contamination with excrement dropped from the passenger coaches or deposited by laborers along the track. In some way or other the Elmhurst Reservoir became infected with typhoid bacilli during the latter part of November, 1906, but, although diligent search was made TYPHOID FEVER EPIDEMICS. 147 by the State Department of Health, the origin of the infection was not discovered. But that the water was infected was made clear by the statistics of the epidemic and by the analyses which were made of the water. ^ The use of this infected water gave rise to an epidemic which extended over the months of December, January, and February, and which resulted in 1155 reported cases and iii deaths during this time. The progress of the epidemic is shown by the following figures: , Week Ending — Reported Typhoid Cases. Week Ending — Reported Typhoid Cases. December 8, 1906 December 15, 1906 December 22, 1906 December 29, 1906 January 5, 1907 14 70 368 269 189 January 12, 1907 January 19, 1907 January 26, 1907 February 2, 1907 74 45 36 II The epidemic began the first week in December, 1906. On November 15, there had been a heavy snow-storm, and this was followed by rains on the i8th and 21st, and on December 3, 6, 10, and 15, one or more of which may have been the means of washing the infectious matter into the reservoir. The Elmhurst water was shut off on December 15, and the city supplied from Lake Scranton; and soon after, the epidemic began to subside. The typhoid fever in the city occurred almost exclusively among the users of Elmhurst water. Dr. Wainright, in commenting on the Scranton ^ It is believed that in at least one sample of this water, the typhoid bacillus was positively identified. 148 TYPHOID FEVER. epidemic, refers to a subject which is too often over- looked. He says : — "One point which I had not fully appreciated, and which, I think, most fail to appreciate, is that typhoid is to a certain extent a directly communicable disease. The Scranton experience has impressed this on me forcibly. Thus, there were 54 families in which there were two cases, and in at least 22 of these the second 110 • 100 90 CO 80 u S70 ^60 UJ |50 Z4O 30 20 10 1 1 '1 !: Mi iiii 1 1 j 1 lilii, 1 i i'l 1 \<'f i»liii Hi vli |i r ''' i^l 1 1 '' I'l I'l M% ^v. Ai J^ "• V^. ^J'f^^-^A A-AA A LJG. SEPT. OCT. NOV. DEC. JAN. DOTTED LINE REPRESENTS CASES DUE TO WATER INFECTION FULL LINE REPRESENTS CASES DUE TO CONTAGION Fig. 12. Diagram Showing the Progress of the Typhoid Epidemic in Gelsenkir- chen, Germany. person aflflicted was definitely found to be the attendant to the patient. There were 7 families which had three cases, and 9 families which had four cases. Among these 16 families having three and four cases, in 8 the TYPHOID FEVER EPIDEMICS. 1 49 attendant was definitely known to have been one of the secondary cases. An interesting fact is that in the families where more than one case occurred, unusual numbers of the secondary cases were children. For example, in the three- and four-case families, out of 35 cases for which I have data as to age, sixty per cent were children." In further emphasis of this point, reference may be made to an epidemic of typhoid fever in Gelsenkirchen, Germany, where a separation of the contact cases from those due to water infection was carefully made. The relative effect of the secondary cases and their tardy occurrence in the epidemic is shown by Fig. 12. One discouraging feature of the Scranton epidemic was the fact that its existence was not recognized by the health department until it was well under way. Wain- right says that "it was the chance finding of a reporter and the recognition of its seriousness by an editor that prevented further fatal delay." From a strictly scientific standpoint, perhaps the most interesting fact about this epidemic is the demonstration that a great reservoir holding nearly a billion and a half gallons of water can become so thoroughly infected with typhoid bacilli as to cause an epidemic that ex- tended over a period of several weeks. The Epidemics of Lowell and Lawrence. During the years 1 890-1 891 a typhoid fever epidemic occurred in Lowell and Lawrence, Mass. As this epidemic illus- trates better than almost any other what occurs on streams which are used both as sources of water-supply and as receptacles for sewage, it deserves more than ISO TYPHOID FEVER. passing mention. Both cities are on the Merrimac River, a large stream flowing through New Hampshire and Northern Massachusetts. On the banks of the Merrimac there are a number of large cities and towns, the most important of which are Concord and Nashua in New Hampshire, and Lowell, Lawrence, Haverhill, and Newburyport in Massachusetts. On the tributaries of the Merrimac are Fitchburg, Clinton, and Marlboro. The sewage of all of these cities finds its way into the river. ^ The water of the river, therefore, was subject to fecal contamination throughout its course. The epidemic first broke out in Lowell in September, 1890, and continued for about five months, during which new cases occurred as follows: Date. Cases of Typhoid Fever . September, 1890 October, i8go November, i8go December, 1890 January, 1891 47 95 171 159 78 550 This epidemic was studied by Professor William T. Sedgwick, who made a most thorough investigation. The situation was complicated by the fact that there ' In 1 890 these cities had the following populations Lowell 77,696 Concord . . Lawrence . Manchester Haverhill . Nashua . . 44,654 44,126 27,412 19,311 Fitchburg . . Newburyport Marlboro . . CUnton . . . 17,004 22,037 13.947 13,805 10,424 TYPHOID FEVER EPIDEMICS. 151 were several distinct systems of water-supply in Lowell. The principal supply of the city was taken partly from a filter gallery, but chiefly from the Merrimac River without purification, the two waters being mixed and pumped together into the city reservoirs. The second system was owned by the Proprietors of Locks and Canals, and was used chiefly for fire purposes, but to some extent for drinking. The supply was river water taken from the canal, and was furnished to most of the mills. There was a third system also taken from the canals and used in a similar way. The fourth and fifth supplies were driven wells and spring waters, which were considerably used on account of the disagreeable quali- ties of the river water. Professor Sedgwick's investiga- tion resulted in tracing the infection to the river water, and connected the beginning of the epidemic with an outbreak which occurred at North Chelmsford, a suburb of Lowell, where there were several cases of typhoid fever in houses that had privies overhanging Stony Brook, a tributary of the ]\Ierrimac River. A short time after the epidemic in Lowell, typhoid fever broke out in Lawrence, nine miles down stream, and rapidly increased. The relation between these two epidemics was most striking. Lowell discharged its sewage into the river, — Lawrence drank the water without filtration. The water-supply of Lawrence was consequently infected with the fecal discharges of the typhoid fever patients in Lowell, and the epidemic followed as an inevitable result. The relation between these two epidemics may be seen from the following figures: 152 TYPHOID FEVER. Month. August, 1890 . September, 1890 October, 1890 . November, 1890 December, 1890 January, 1891 . February, 1891 March, 1891 . April, 1 89 1 . . May, 1891 . . Lowell. Number of Deaths. 28 26 19 14 10 6 4 Death-rate per 100,000. Lawrence. Number of Deaths. 3 3 7 19 19 II 6 3 Death-rate per 100,000. 2 . 24 6-73 6-73 15-71 42.64 42.64 24. 69 13-46 6-73 4.49 It will be seen from these figures and from Fig. 13 that the climax of the Lawrence epidemic occurred about one month after that in Lowell. In 1892 there was a repetition of this epidemic. Typhoid fever in Lowell was again responsible for an increase of typhoid fever in Lawrence. The situation was not as serious as that of two years before, but this time Newburyport was also affected. The relation between the three cities is shown by the following figures : Lowell. Lawrence. Newburyport. Date. 1 Cases. Deaths. Cases. Deaths. Cases. Deaths. November, 1892 .... 19 3 14 4 December, 1892 .... 70 ID 32 9 4 I January, 1893 3« 10 72 3 28 3 February, 1893 14 7 23 12 9 March, 1893 4 4 I TYPHOID FEVER EPIDEMICS. 153 It is said the reason for the Newburyport epidemic was that the " Newburyport water company had distributed to the cities more or less water drawn unpurified directly from the Merrimac River, contrary to recent specific ad- vice of the danger of so doing addressed to them by the State Board of Health, and referring especially to the Fig. 13. Diagram Showing the Chronological Relation between the Lowell and Lawrence Typhoid Fever Epidemics. likelihood of an outbreak of typhoid fever if they should continue to do so." In justice to these cities, it should be said that they now have safe and wholesome water-supplies. Lowell abandoned the river, and introduced a ground water- supply, while at Lawrence a filtration plant was con- structed which has very materially reduced the amount of typhoid fever in that city. 154 TYPHOID FEVER. The Epidemics of Waterville and Augusta. In 1902-3, an epidemic of typhoid fever occurred in the cities of Waterville and Augusta, Me., which furnishes an inci- dent almost parallel to the Lowell and Lawrence epidemic of 1890-1. These cities are situated on the Kennebec River. Augusta is the capital of the state, and Waterville, 18 miles up the river, is an important manufacturing city. The city of Waterville was supplied with water from the Messalonskee system by the Maine Water Company, which also furnished water to the neighboring towns of Fairfield, Winslow, and Benton. The system has a watershed of 205 square miles, and drains a chain of large lakes. The population on the watershed was 27 per square mile, the principal source of pollution being the town of Oakland, 7 miles above the pumping station, where the population was about 2000. Waterville discharged its sewage into the Kennebec River. Augusta, at this time, took its supply from the river at a point just above the city near the Kennebec dam. The water was pumped to a reservoir through an old Warren filter, one of the first of its kind in America. This was a filter only in name; it was really no more than a strainer, and wholly inefficient in removing disease germs from the water. Augusta discharged its sewage into the river. The town of Richmond, 15 miles below Augusta, also took its water unpurified from the Kennebec River. The epidemic was very carefully studied by the author, assisted by Dr. E. C. Levy and Mr. Langdon Pearse, in connection with the appraisals of the water- works of the two cities, as it was necessary to prove in TYPHOID FEVER EPIDEMICS. 155 court the probable origin of the trouble and its connec- tion with the public water-supplies. In fact, it was largely due to these epidemics that steps were taken to transfer the ownership of the works from the private water companies to the water districts, which represented the people. The epidemic was first noticed at Waterville, in November, 1902. For about a month new cases were reported at the rate of one a day. On Christmas Day there were five new cases, and during the next week the daily number of cases was about the same. Thirteen were reported on New Year's Day. After the middle of January the number of new cases fell off, but they continued to be reported at intervals until March. In Fairfield, Winslow, and Benton, typhoid fever occurred at the same time. The largest number of cases was reported during the first two weeks of January. These four communities had the same water-supply, namely, that oi the Messalonskee River, and from the first it was evident that this was the cause of the epidemic. As the sewage of these typhoid-fever-stricken communi- ties emptied into the Kennebec River, and as the water of this river furnished the supply of Augusta, it was almost inevitable that the epidemic should extend to that city also, and this is what actually occurred. During the latter part of November and the whole of December new cases of typhoid fever occurred daily in Augusta. It seems probable that these earlier cases were due to the same source of infection that caused the epidemic at Waterville, inasmuch as the Messalonskee River, which supplied that city, discharged into the Kennebec 156 TYPHOID FEVER. above Augusta. It was not until about two weeks after the climax of the Waterville epidemic that the serious period of the Augusta epidemic began. During the latter part of December and throughout the months of January and February the sewage at Waterville must have been infected with typhoid fever bacilli; and, making due allowances for the periods of sickness, transmission, and incubation, this time corresponded with the duration of the epidemic at Augusta. After the Waterville epidemic had ceased and sufficient time had elapsed for the patients to recover, the epidemic at Augusta came to an end. At Richmond, which is only a small village, typhoid fever did not occur until the middle of January; but occasionally cases appeared during the next two or three months, and were plainly connected with the epidemic of the cities above. Fig. 14 shows chronologically the progress of this epidemic, together with certain factors which affected it. It indicates that the epidemics in the different com- munities formed a connecting series, and may be really considered as one epidemic, inasmuch as they started from a common cause. In all there were about 612 cases and 53 deaths. The epidemic at Waterville was traced to two cases of typhoid fever which occurred on the watershed above the intake. The first of these was at the city alms- house located in the suburbs of Waterville only a few hundred feet from the stream. On September 22, 1902, a typhoid fever patient was admitted to the almshouse. His attack was a mild one, and he was confined to his bed for only a week; but after leaving his bed he remained AUGUSTA WATER DISTRICT TYPHOID FEVER EPIDEMICS. 1 57 five days at the almshouse, and during this latter period no attempt was made to disinfect either his excreta or urine, which were deposited sometimes in a privy in the yard, and sometimes in a water-closet which drained into a cesspool on the premises. On November 6, both the privy and cesspool were cleaned and their contents spread upon the almshouse garden, the ground being frozen at this time. The slope of the garden was towards the river. The second case occurred about a mile outside of Waterville, in the family of a milkman. During 1902 there had been five cases of typhoid fever in this house. In all of these cases except one, a prompt diag- nosis had been made, and the dejecta were properly disinfected and buried, but in one case the patient was ill for several weeks before the diagnosis was made. During this time, i.e., from September ist to 25th, 1902, disinfection was not practiced, and the stools were emptied into the privy vault. Early in November the privy was cleaned and the contents deposited on a field away from the house at a point where the land sloped abruptly towards a brook 200 feet distant, this brook being tributary to the Messalonskee Stream three-quarters of a mile away. Both the almshouse and the mouth of this stream were about one mile distant from the water- works intake. Thus, early in November, 1902, typhoid fever dejecta had been deposited upon the surface of frozen ground at two points relatively near the pumping station. During November and the first part of December the rainfall was light, and there was some snow, but apparently 15^ TYPHOID FEVER. during this time small amounts of infectious matter were washed into the stream. On the i6th of December there was a heavy rain, and nine days later, on Christmas Day, the main epidemic began. The heaviest rainfall, after the infectious material was deposited on the fields occurred on December 22, with a precipitation amounting to 1.3 inches. Ten days after this, or almost exactly the same interval as after the rainfall of December 16, there developed the greatest number of cases of any which occurred during the epidemic. Throughout the two months, from the last third of November until the corresponding time in January, the relation between the rainfall in typhoid fever cases was manifest. About the middle of January the typhoid bacilli had either lost their vitality, or had been washed away, as subsequent heavy rainfalls were not followed by serious consequences. Profiting by their experience, the cities of Waterville and Augusta have both abandoned the use of the river water, and now take their suppHes from lakes at a con- siderable distance from the city. The Pittsburg and Allegheny Epidemics. For many years the cities of Pittsburg and Allegheny, Pa., have been in the throes of a typhoid fever epidemic which has spread its baneful influences over the western part of the state, and scattered the disease even more widely through the agency of many an unfortunate visitor and traveling man. It is one of the black records in the sanitary history of our country. These two cities are situated at the confluence of the Allegheny and Monongahela Rivers, — where TYPHOID FEVER EPIDEMICS. 1 59 they unite to form the Ohio River. In 1900 Pitts- burg had a population of 321,616, and Allegheny 129,896. Pittsburg takes its water from the Allegheny River at Brilliant Station, six miles above the junction of the rivers, and from the Monongahela River, at a point three miles above the junction. The first-named supply is under municipal control, and furnishes about three- quarters of the supply delivered between the rivers in Wards i to 23. The second is operated by a private company, and supplies Wards 24 to 36, south of the Monongahela River. In neither case is the water puri- fied, and the period of storage in the distribution reser- voir is inconsiderable. Both rivers are contaminated by the sewage of large communities, some of them only a few miles from the city. The water is at times muddy and disagreeable. The urban population in 1900 was 28 per square mile on the Allegheny River, and 26 per square mile on the Monongahela. The statistical data showing the occurrence of typhoid fever are given elsewhere in this volume, so that in this connection it is only necessary to state that in this unfortunate city there occur annually upwards of 5000 cases of the disease. It is scattered all over the city, but, on the whole, the wards supplied with Allegheny water suffer the most. It is present at all seasons, but is more prevalent in the fall and winter months than in cities supplied with good water. The Pittsburg case is instructive, as it illustrates the dangers of procrastination. Ten years ago and more, it was known that the public water-supplies were infected. i6o TYPHOID FEVER. Fig. 15. TYPHOID FE\^ER EPIDEMICS. l6l The best methods of filtering the supply were determined in 1898 by an elaborate series of experiments. Delays followed, and, although a filter plant is now under con- struction and nearly completed, it is not yet ready for use.^ The delay has cost the city at least 2000 lives, — possibly 3000, — and has brought unnecessary sick- ness into more thousands of homes. The case of Allegheny is equally bad. The water- supply is taken from the Allegheny River at Montrose, 10 miles from the Point, and is drawn from a rock- filled crib. It is practically unfiltered water, grossly contaminated. Allegheny is smaller than Pittsburg, but its typhoid fever death-rate has been even higher. These communities have been singled out for comment not because they are the only instances of epidemics due to long-continued contamination of the water-supply, or because they are the only cities which have failed to live up to the light within them. Philadelphia has been equally culpable, and other cities might be named. Pittsburg, however, is a very clear-cut case. The Chicago Epidemic. Chicago, the second largest city in the United States, situated on Lake Michigan, had for many years a water-supply that was constantly being contaminated with the discharges of her own sewers. The water was taken from the lake opposite the city at several "cribs," which were 1.5 to 4 miles off shore. Sewers were discharged all along the water-front; while the Chicago River, penetrating the city with its north and south branches, and polluted almost beyond endur- ance, flowed into the lake about midway between the ^(January, 1908.) 1 62 TYPHOID FEVER. upper and lower cribs. That intense pollution of the lake water, and hence of the water-supply of the city, resulted from this situation was well known. It needed no elaborate studies, for at times the foul river water could be traced to the intakes with the eye. This intolerable situation resulted in the building of the Chicago Drainage Canal, the object of which was to take the sewage out of the lake and carry it westward down the DesPlaines and Illinois rivers into the Mississippi, — a project, recently consummated, which has given rise to some important litigation before the United States Supreme Court between the states of Missouri and Illinois. By the construction of this canal the flow of the Chicago River was reversed, so that, instead of the sewage entering the lake and polluting the water-supply, the water of Lake Michigan with the greater part of the sewage now flows westward to the Mississippi and to the Gulf of Mexico. What- ever the effect of this has been on the cities along the Illinois and Mississippi rivers, this canal has improved the water-supply and reduced the amount of typhoid fever in Chicago. As an illustration of an epidemic caused by contam- inated lake water, the Chicago situation during the years 1890, 1891, and 1892 affords an important example. Within one fatal year nearly 2400 of the inhabitants died from typhoid fever, and these deaths probably represented at least 25,000 cases. The following figures show the number of deaths each month: TYPHOID FEVER EPIDEMICS. 163 Month. Deaths from Typhoid Fever. 1890. 1892. January . . February . . March . . . April. . . . May .... June . . . July . . . . August . . September . October . . November . December . Total 53 136 103 45 82 107 "5 95 72 67 47 1008 67 61 71 136 408 167 200 182 171 150 311 187 76 56 70 55 211 179 138 92 67 47 1997 Although typhoid fever had been very abundant in 1890, the greatest period of the epidemic began in April, 1 89 1. It continued without a break for nearly a year; then came a decrease, and then for several months the deaths increased again. Epidemics due to lake pollution are quite likely to be of long duration, for the reason that, as the epidemic increases in severity, the sewage of the city becomes more and more infected, and this increases the number of typhoid bacilli in the water. Such an epidemic tends to perpetuate itself, and may continue until all susceptible persons have had the disease, or until the conditions of winds, currents, etc., are such that for a time the contamination of the water ceases. In 1902 another epidemic occurred in Chicago, — 164 TYPHOID FEVER. CHICAGO, ILL. DIAGRAM SHOWING THE POPULATION NUMBER OF DEATHS FROM TYPHOID FEVER AND THE TYPHOID DEATH RATES BY YEARS. 1000 Fig. 16. TYPHOID FEVER EPIDEMICS. 1 65 less in magnitude than the one just described, but yet one which caused the annual number of deaths to increase from 337 in 1900, to 509 in 1901, and 801 in 1902. This epidemic came as a surprise to many of the citizens of Chicago, as they had been led to believe that the new drainage canal would effectually act as a safeguard to the water-supply. But the explanation was obvious. Although the drainage canal was opened in 1900, not all of the sewers had been connected with it, — the intercepting sewer along the south shore, and the Lawrence Avenue sewer on the north side, for example, had not been completed, — so that a considerable part of the city continued to discharge its sewage into the lake. The epidemic began early in the summer. The 193 persons who died in August probably contracted the disease in June or July. It was noticed that the rainfall during May, June, and July of that year had been exceptionally heavy, — larger, in fact, than for any corresponding period since the epidemic of 1892.^ At most times the typhoid fever records of the city show a general correspondence between the rainfall and the occurrence of typhoid fever, although, as might be expected, this relation has not been quite as marked Year Rainfall during May, June, and July. 1892 19-58 1893 1894 5- 189s 5- 1897 • • ■ 5 1898 9 1899 13 1900 10 1901 , 8 1902 ................:.... 17 1 66 TYPHOID FEVER. since the drainage canal was put in service as it was before. The annual report of the Department of Health for 1906 refers to the low rainfall of that year as one reason for a reduced typhoid death-rate. Recently the typhoid death-rate in Chicago has been lower than formerly; but from the nature of the sanitary conditions along the water-front, and the inevitable contamination of the water resulting from shipping and other causes, there is no reason to expect that the city will ever have a permanently low typhoid death- rate until the lake water is filtered. The Cleveland Epidemic. Another instance of an epidemic caused by contaminated lake water is that of Cleveland, Ohio. The city of Cleveland is situated on an indentation in thC' southern shores of Lake Erie, about two-thirds of the way from Toledo to Buffalo. This indentation, or bay, is about 40 miles long and 7 miles wide, and within it the water is nowhere deeper than 60 feet. The Cuyahoga River flows into the lake through the heart of the city. The water-supply of the city is derived entirely from the lake. The old intake, which was used until 1904, was located about i| miles from the shore and i mile west of the mouth of the river, the water being taken at depths of 12 to 28 feet below the surface, and conveyed by two tunnels to the pumping station at Division Street. In order to supply a greater quantity of water, and at the same time to secure water of a better quality, new works were begun in 1890 and completed in 1904. The new intake is located 4 miles from the shore, almost opposite TYPHOID FEVER EPIDEMICS. 1 67 the mouth of the Cuyahoga River. From the steel crib a 9-foot tunnel conveys the water to a pumping station on the shore of the lake at Kirtland Street. All of the sewage of the city flows directly or indirectly into the lake. About one-half of it flows into the Cuya- hoga River, and the rest empties directly into the lake along the water-front. It has been estimated that the amount of solid matter discharged into the lake through these sewers amounts to 100 tons a day, while the number of bacteria contained in it amounts to more than 100 million billion. These figures are incomprehensible, and mean little except when taken in connection with the subject of dilution. Beside the pollution from the river and the sewers, the water-supply of the city was at that time endangered by the practice of dumping dredged material from the river at points dangerously near the intakes. During the year 1903, when the water-supply was drawn wholly from the old intake, a severe epidemic broke out in the city. This continued throughout the entire year, and extended over the spring months of 1904, ending only with the introduction of water from a new source. In order to understand the course of this epidemic, it is necessary to know that under ordinary conditions the Cuyahoga River water and the sewage of the city become so thoroughly mixed and diluted with the water of the lake that the effect of contamination is not serious a mile or two out from the shore, but that at times of heavy rains which cause floods in the river, and especially at those times when the floods occur in connection with 1 68 TYPHOID FEVER. an off-shore wind, pollution reaches the old intake crib in such quantities as to grossly contaminate the water- supply. A study of the typhoid data prior to 1903 showed that after severe southeasterly storms there was likely to be an increase of the disease in the city. The investigations made in connection with the epidemic referred to showed that at the point where the new intake was located, 4 miles off the shore, the influence of the city sewage on the lake water was extremely slight, although, even at that distance, there were times when traces of it could be detected. The epidemic of 1903 began on January 6, when 9 new cases were reported. Ten days before this there had been a heavy rainfall which increased the discharge of the river, and which was followed by fresh south- easterly winds. It is unnecessary to explain here all the fluctuations in the typhoid morbidity which occurred during this year, but the data show that the wind exerted the con- trolling influence on the typhoid fever in the city. (See Fig. 17.) During the year 1903 the total num- ber of cases reported was 3443, and there were 472 deaths. The severest part of the epidemic occurred early in 1904, beginning after a memorable flood on January 20, 21, and 22. On these three days the rainfall aggregated 2.57 inches, while the wind blew strongly from the south- east. Moreover, on the day preceding this storm the southeasterly wind movement had been 515 miles. On January 21, the discharge of the Cuyahoga River was (N O 03 JAN. FEB. MAR. !,APR. MAY JUNIE i; li CASES OF TYPHOID .FEV 1 l 1 \ y^,y,,,X,^.y,^ ^^^^^^^ iO ^WuJS/^ h^^.A^..S/\fs::KAj 1 '• " n \^ A A,A. X'"-- hnL.:^ > WATER SUF^PL: o CASES OF TYPHOID FEVER BY DAYS I J DEATHS FFjOM ■-YPHGII^IIFEVER BY MONTHS WATER SUPPLY FROM NEW CRIB K\m\m\\v\m\vvmW JULY AUG. SEPT. OCT. NOV. DEC. 10000 8000 6000 4000 FROM OLD CRIB" o o UJ CO cc Ui Q. h- Ul lU u. 8000 2 OQ O 4000 Z 2000 12000 10000 6000 ■ROM OLD CRIBj 1 1 ' ' 1 i '1 1 ' 1 i'l"Ti|r '1 !'■ ■I'lUT 'II r|i'|iri||i ii - WIND MOVEMENT IN MILES ^ - DISCHARGE OF C UYAHOGA RIVER ]^ CUBIC FEET PER SECOND I i ; U — ^ -, ^, xum^ ^ \AA=jk,»AAj \ .',:-yyMy.y)yJJ WATER SUPPLY FROM NEW CRIB CLEVELAND, OHIO. ^\s■-^^^^^^\^^^^^^^^N^\^^\^^^^\^^^^^^^^\\^■^^^ lOOOO 8000 ^^ DIAGRAM SHOWING THE REDUCTION OF TYPHOID FEVER FOLLOWING THE CHANGE IN THE SOURCE 4000 OF THE PUBLIC WATER SUPPLY FROM THE OLD 0(jQQ TO THE NEW CRIB. V\\\\\\\'y\\'~.W\\\\\\\xl 2000 18000 16000 S 100 i 200 5 300 I iiJO S .500 ^: 8000 6000 4000 2000 CC LU > CC < o O I < > o u. o UJ o cc < I o CO a tu < X o cc a. a. <. TYPHOID FEVER EPIDEMICS. 169 Fig. 18. I/O TYPHOID FEVER. very great, and immense quantities of mud were carried into the lake, possibly 200,000 cubic yards, or more than is ordinarily discharged during an entire year. On January 31, ten days after this flood, typhoid fever began to increase in the city, and this increase continued until February 10, when 25 new cases were reported in one day. On February 6 and 7, there was another southeasterly storm which caused a flood in the river. Although the stream discharge was less than before, the sewage of the city had become so thoroughly infected that the amount of typhoid in the city increased more than before. A week of calm weather followed, and the amount of typhoid fever in the city dropped off. On the 13th and 14th of February there was another strong southeast wind, and ten days afterward the morbidity rate rose again, and so the epidemic continued, until a change came in the source of supply. During the 16 months from January, 1903, until May, 1904, there were 4578 cases of typhoid fever reported to the Health Department, and 611 deaths. The introduction of water from the new intake occurred gradually. The Kirtland Street station, where water was taken from the new intake, was started on February 10, 1904, and the pumps at the Division Street station, the old supply, were finally shut down on April 7. Between these two days, water was drawn from both intakes. As the proportion of water from the new intake increased, the typhoid fever in the city began to disappear, and finally, after the old supply had been entirely abandoned, the epidemic ceased. The following figures show the close relation between this change in the TYPHOID FEVER EPIDEMICS. 171 character of the water-supply from bad to good, and the decrease in the typhoid fever. Period. Average Number of New Cases of Typhoid Fever Reported Daily. January i, to January 31,1904: Period prior to the epidemic caused by flood February i to March 5: Period of epidemic corre- sponding to exclusive use of old supply March 6 to March 15 : Period of epidemic correspond- ing to use of one-half of supply from new intake and 2.84 20.91 II. 10 March 16 to April 21 : Period of epidemic correspond- ing to use of three-quarters of supply from new intake . 2.89 April 22 to December 31: Period corresponding to exclusive use of water from new intake 1.03 The Burlington Epidemics. The city of Burlington, Vermont, is located on Lake Champlain. In 1866 it introduced a water-supply, taking the water from the lake at one of the docks near the city where the pumping station was located. Somewhat later, sewers were built which discharged into the lake less than half a mile away from the waterworks intake; but in 1885, on account of excessive pollution, the outfall sewer was removed to a distance of one mile. This, however, did not relieve the situation, and typhoid fever and other forms of diarrheal diseases were prevalent until 1894, when the waterworks intake was extended two miles and a half into the lake to a point near Appletree Island. 172 TYPHOID FEVER. After this change in the supply there was a reduction of typhoid fever in the city; but during the last ten years, the death-rates have shown a tendency to increase, while 00 o CO 00 ■^ CD r^ 00 o> o 00 '" o o CJ> '" / T 1 150 100 50 WAjTER EPIDEMIC ITHACA, N.Y. 4 5 6 WEEKS Fig. 23. Diagram Showing Two Types of Epidemics. origin of an outbreak. The following curves represent rather exaggerated cases of two of these types of epidemics. Attempts have been made to establish a relation between the intensity of infection and the severity of the TYPHOID FEVER EPIDEMICS. 211 disease, but generally without much success. In out- breaks due to milk or oysters, one would naturally expect the infection to be severe, the dose of bacilli to be larger, and, in consequence, the disease to be more violent, or the period of incubation shorter. To a certain extent this is true, but in all probability the severity of the fever depends more upon the constitution of the persons infected than the intensity of the infection. Yet one may readily conceive how typhoid bacilli might retain a greater degree of vitality, and presumably of virulence, in such a good culture medium as milk than in an unfavorable medium like water. There may be also different "strains" of the bacillus, — some of which are more virulent than others, — but such speculation as this carries us beyond the known facts of science. There is some reason to believe, however, that the incubation period is shorter and more uniform in the case of intense infections due to milk or to direct contact than in the case of the water-borne type of the disease, when the attenuation of the bacteria is often greater. Warnings, It is a famihar saying that "Coming events cast their shadows before." This is very true of typhoid fever epidemics, although not universally true. It has happened on many occasions that an outbreak of typhoid fever has been preceded by an unusual prevalence of diarrheal troubles, — winter cholera, etc. Examples of this have been already referred to. These milder disturbances have a shorter period of incubation than typhoid fever, hence they are manifested earlier. Thus, within a day or two after the mayoral banquets at Winchester and Southampton many of the guests were 212 TYPHOID FEVER. taken ill with intestinal troubles, but the typhoid fever did not develop for ten days or so. So also in the case of the steamer "Northwest." The prevalence of diarrheal diseases in any community, especially during the winter, should be regarded therefore as a warning of an impending calamity. One of the best illustrations of the sequence of typhoid fever, with its comparatively long incubation period, and intestinal diseases which make a more sudden attack, is that of Hamburg, Germany, during the cholera epi- demic of 1892-93. The following figures show the morbidity for these two diseases. Week Ending — Cases of Cholera. Cases of Typhoid Fever. 1892. August 20 .... 27 .... September 3 .... 10 .... 17 .... 24 .... October 8 .... IS .... 22 .... 29 .... November 5 .... 12 .... 20 .... 27 .... IIS 3593 6157 3217 2092 1224 lOI 41 14 I 3 S 4 3 42 38 69 139 15s 132 76 52 43 34 32 21 15 14 Infection Widespread. The question is often asked, " Where does the original infection come from ? " Some- times in an outbreak this can be traced; more often it cannot. But a few moments' thought will show that TYPHOID FEVER EPIDEMICS. 213 there is no lack of supply of typhoid fever in the United States. Suppose the average death-rate from this disease throughout the cities of the country to be 35 per 100,000. That means at least 350 cases per 100,000 per year, — or, say, one case each year to every 250 or 300 persons. In many rural districts the disease is even more prevalent than this. Such being the case, there are sure to be some cases of typhoid fever among the thousands of farmers who send milk to the great cities, and who handle the other food supplies. The sewage of all large cities certainly contains the typhoid bacillus at some time in the year. Then there are the "typhoid carriers" and the resistant typhoid cells that are long lived and that may exist for months in the contents of a privy or cesspool, or in the mud at the bottom of a stream behind some dam. When all these facts are taken into consideration, the wonder is not that there is so much typhoid fever, but that there is so little. Many more epidemics might be referred to, and doubtless better examples than those cited might have been picked out, — but enough have been given to illustrate the main sources of infection. In some cities supplied with impure water, there is a constant suc- cession of epidemics, — a new infection occurring before the last has loosened its hold. And all over the country miniature outbreaks are occurring by the hundred. Few of them reach a place where they attract other than local attention; no serious attempt is made to ascertain their origin, — and so they would go on, widening their circle of influence, were it not for the checks imposed by sanitary science. 214 TYPHOID FEVER. Epidemics as Life Savers. Strange as it may seem, the great epidemics have done more than almost anything else to reduce the typhoid death-rate of the country, for, by reason of their severity, they have imperatively demanded that their cause be ascertained and prevented. They have stimulated research, enlightened the public as to the principles of sanitary science, and compelled city officials to apply these principles for the good of the people. They have aroused careless cities to the need of a pure water-supply; caused laws to be passed pre- venting the sale of oysters fed near the sewers; and increased the vigilance of milk inspection. They have awakened physicians, and citizens as well, to the sense of their public responsibilities in a way that the constant presence of a high death-rate will never do. These epidemics are usually set forth as terrible scourges, — and so they are, locally considered, — but they influence the general death-rate of the country very little. Or, mathematically expressed, a very high death-rate applied to a small population causes fewer deaths than a moderate death-rate applied to a large population. Thus, during the famous epidemic year in Ithaca, N.Y., in 1903, the death-rate rose to 625 per 100,000, which, applied to a population of 13,156, meant 82 deaths. During the same year the average death-rate for the state of New York was only 21.5 per 100,000, but this, applied to the total population of 7,600,000, meant 1665 deaths. The epidemic attracted attention; the moderate death-rate did not. So, too, in the Spanish War, the shameful occurrence of typhoid fever in our TYPHOID FEVER EPIDEMICS. 21 5 military camps aroused general indignation, while in the Southern states and elsewhere in the country, the rural death-rate, far more reaching in its effects and sweeping away a far greater army of victims, goes on year after year almost without comment. CHAPTER IX. THE INVESTIGATION AND CONTROL OF TYPHOID FEVER EPIDEMICS. The study and control of typhoid fever outbreaks and epidemics is naturally a function of the health authority, — the local board of health, or health officer, if there is one, or the county or state board if there is no competent local authority. The matter, however, is one which usually demands quick action and the sound judgment which comes from experience, and hence it is becoming quite common for experts to be called in to assist the local authorities or to take charge of the situation. To trace an epidemic to its source is not so much a study for the doctor as for the statistician, the detective, the bacteriologist, the chemist and the engineer. The specialist has to be all of these at once. The local physician is sometimes, but not always, equipped for the task. The expert is more likely to see the facts in their true perspective; he is also more likely to obtain the cooperative assistance of all parties interested; and he is less likely to be influenced by the confusion of ideas which often occurs when a community suddenly finds itself face to face with a scourge of unknown origin. In taking up the investigation of an epidemic with 216 CONTROL OF TYPHOID FEVER EPIDEMICS. 21/ a view to its control there are four principal things that have to be done: First. It must be ascertained whether or not the disease is actually present, and whether it is present, as a general epidemic or merely as a local outbreak. Second. The cause must be discovered. Third. The cause must be removed. Fourth. The spread of the disease must be prevented. Collection of the Data. The local board of health, from its physicians' reports, should be the first to learn of the existence of a typhoid increase, but often the first note of warning comes from rumor or from the daily press. Of course, if the physicians fail to report, the board of health has no facts; but if the returns are made and are merely tabulated, but not studied from day to day, then the health ofiicers have failed in their duty. In the orderly working of a health department any increase in the reported new cases of typhoid fever would lead to an immediate study of each case, and to a special inquiry among the physicians as to the pres- ence of other suspected cases. By so doing an epidemic would often be nipped in the bud, without alarming the community. There is perhaps no place where the saying so well applies as here, that "a stitch in time saves nine." It happens more often, perhaps, that the extent of a typhoid outbreak is unduly magnified. A reporter, seeking copy, starts a typhoid scare, and alarms the people and injures the reputation of the city. The first thing of importance, therefore, is to find out who have the disease, where they live, and where they 2l8 TYPHOID FEVER. were taken sick. These and various other statistics are needed in tracing the epidemic to its source. The necessary data are seldom reported to the heakh depart- ment with sufficient completeness, and nearly always a special canvass has to be made. The names and addresses of the patients having been obtained from the health departments and from the physicians, house- to-house visits are necessary for the sake of obtaining first-hand information as to the onset of the disease, the history of the person as to the use of water, milk, food, etc., and for the sake of making a sanitary inspection of the premises. If the epidemic is an extensive one it is convenient to record the various data on printed forms drawn up to fit the special case. The principal data required are the following, but other items will naturally suggest themselves in particular cases. SCHEDULE OF DATA NEEDED IN THE STUDY OF TYPHOID FEVER OUTBREAKS. Number of case (for reference) Name of patient ? Residence ? Physician's name and address ? Date of physician's report ? Character of house (private house, boarding house, apartment, hotel, etc.) ? Age ? Sex ? Occupation ? Place of business ? Where living month previous to illness ? - — . Absence from home previous to illness ? If so, where ? " Date of first symptom ? Date of taking bed ? Date of doctor's first call ? CONTROL OF TYPHOID FEVER EPIDEMICS. 219 Date of leaving bed on recovery ? Date of relapse ? Date of death ? Blood examined? Date? Result? Spleen enlarged ? Rose spots ? Sanitary condition of premises ? Source of drinking water, — at home ?. . . at business ? Elsewhere ?. . Milk supply from? Milk habitually drunk? Raw oysters eaten ? Source ? Patient has separate room ? Nurse ? Were stools disinfected ? the urine ? Any other precaution taken ? Other cases in house ? (Obtain names and dates) Other cases among business associates ? Schoolmates ? Friends ? Number of people in the house Remarks: Information given by. Information given to. . Date of information. . (Signed). Study of the Data. As fast as the data are obtained they should be tabulated and studied from various points of view. Were the cases generally distributed over the city or were they confined to one locality ? A convenient method of ascertaining this is to take a street map and locate the cases with black-headed pins stuck in at the place of residence. This map, with its pins, can afterwards be photographed for record. If the cases are localized, does the locality suggest anything as to a common cause? Is it coincident with some particular water-supply, as it was in New Haven, or with some milk dealer's territory, 220 TYPHOID FEVER. as in Somerville? Is it located in a section where there are no sewers, as in Winnipeg? Is it around some public well, as in Newport? Or are the cases merely concentrated in one place because the population is densest there? Does the geographical distribution of the cases change as the epidemic progresses ? Where were the early cases with respect to the others ? What was the probable date of infection? Was there a sudden, sharp attack, or was the onset gradual? If the latter was the case, what were the limiting dates of infection? The date of infection has to be estimated by counting back from the time when the patient was taken sick. All things considered, the safest date to count from is that of taking bed. Often this cannot be learned, especially if the investigation is made sometime after- wards. But the date of going to bed is seldom far from the time of the physician's first call, and this can usually be obtained from the doctor's memoranda. If the epidemic is believed to be due to milk, or oysters, or some other cause involving an intense form of infection, the probable date when the patient received the bacilli into his system may be obtained by counting back 7 to 10 days; but if a water infection is suspected, a period of ID to 15 days will probably give a better estimate. It must be remembered, however, that occasionally the period of incubation may be considerably longer than this. Sometimes it is necessary to count back from the appearance of some particular symptom, and in that case the attending physician's advice should be obtained as to whether this occurred in the second or third or fourth week of the disease. Sometimes one has to figure CONTROL OF TYPHOID FEVER EPIDEMICS. 221 back from the date of death. That also is something about which the attending physician should be consulted. Were there any outbreaks of diarrhea preceding the typhoid epidemic? When and among whom did they occur ? Were most of the cases among young people and children? If so, this suggests milk as a cause. Did they all or most of them use the same water-supply, or take milk from the same dealer, or food from the same source ? Had the patients been together anywhere, at business or in school, or at some banquet? In short, was there any common cause where eating or drinking or association might give opportunity for infection ? If the public water-supply is suspected, investigations should be carried on to determine whether or not the source is a satisfactory one, whether it was contaminated with fecal matter, and whether, finally, it was infected from some particular case. This is such a broad sub- ject that it cannot be fully gone into here. The aid of the bacteriologist and chemist usually has to be invoked, and the interpretation of his analyses is an important matter and one where his judgment is of equal weight with the figures themselves. It must be remembered, however, that as a practical test, the bac- teriologist cannot tell whether or not the typhoid bacillus is or is not present in a sample of water. He may find the colon bacillus, the intestinal germ, and that will indicate fecal pollution, i.e., domestic or animal con- tamination, but it will not prove of itself that the water 222 TYPHOID FEVER. is infected. Analyses are nearly always very valuable and even necessary, but too much must not be expected of them, particularly as the samples of water are often not collected until many days after the date of infection. An inspection of the source, with particular respect to the occurrence of typhoid fever near it, is of the utmost importance. In connection with a study of the water-supply the meteorological conditions should be taken into account, — the temperature, the rainfall, the occurrence of melt- ing snows, floods, etc. If the milk-supply is suspected, inspections of the various farms should be made, their sanitary conditions noted, their well-waters, — and especially the occurrence of typhoid fever, or "grippe," or "bilious fever," or "slow fever" or something that might be typhoid in masque- rade, in the farmer's family or among his employees. The transportation of the milk and its distribution should be studied with reference to cleanliness and to the occurrence of the disease among those employed. In connection with oysters it must be remembered that they may be infected at their layings, or during the process of floating, or during their handling. By far the greatest chance of infection, however, comes from the practice of floating in sewage-polluted waters. In most cases these various investigations are not made serially, as described, but are all carried on together, and as rapidly as possible, in order to learn the cause. Sometimes an expert, because of his experience, is able to size up the situation very promptly ; whereas, if left to local study, it may take a long and careful investi- CONTROL OF TYPHOID FEVER EPIDEMICS. 223 gation. In any study of a typhoid fever outbreak one should not be led into a blind attempt to trace the disease to some well-recognized cause; for it must be remembered that science does not yet know all the means by which the germs of the disease may be spread. The student should familiarize himself with the best methods of procedure, by a careful study of the detailed reports of several typical epidemics. The Control of Epidemics. The control of a typhoid fever epidemic is a subject upon which little need be said, after what has gone before. Obviously there are two lines of action required — the removal of the original cause, and the prevention of the spread of the disease. The actual character of the work to be done naturally depends upon circumstances, but in a general way it consists of putting into practice the various sanitary measures that unite to form the three barriers of enclosure and the three lines of defense described in earlier chap- ters, — with this exception, that these lines have to be drawn more strictly than under ordinary conditions. If the cause of the epidemic has been ascertained beyond reasonable doubt, the course to be pursued is usually clear. If the cause has not been definitely ascertained, it may be necessary to take into account one or more suspected causes, and to act in each case as though it were the real one. This naturally involves some unnecessary work, but usually the matter is so serious a one that it is not wise to take any chances or leave any stone unturned. If a well water has been found to be infected, it is a comparatively easy matter to discontinue its use, dis- 224 TYPHOID FEVER. infect the well and thoroughly clean it out; if a milk- supply is at fault, a thorough process of cleansing and disinfection will prevent further trouble; but if the public water-supply is found to be the cause, the situ- ation is a far more serious one, and one which calls for the exercise of greater skill and experience. Just what to do is often a difficult matter to decide, as much depends upon whether the infection is a transient one or one that is likely to persist for some time, and whether the infected source is the only water-supply available. If a city has more than one supply it may be possible to discontinue the use of the one that is suspected as being the cause of the epidemic, and depend for a time upon the other sources. But more often, perhaps, the conditions are such that this cannot be done, and that the supply, even though infected, cannot be shut off without leaving the city without fire protection. In this case the only thing to do is to discontinue its use for drinking, as far as this can be done, and to depend upon boiling the water in those houses where no other supply can be obtained. In some cities it has been found possible to temporarily furnish the citizens with spring water, distributed without charge, or for a merely nominal charge. In some cases efforts have been made to disinfect the entire public supply in order to render it safe. This, however, is very difficult of accomplishment, except in very small supplies; in large supplies it is practically impossible. Copper sulphate has been held up as a safe and efficient chemical to be used for this purpose, and no doubt its use in some cases would be beneficial, CONTROL OF TYPHOID FEVER EPIDEMICS. 225 but there are reasons to believe that it is not an adequate remedy. Dilute solutions of copper salts will kill a large percentage of typhoid bacilli, but stronger solutions seem to be required to kill the more hardy forms which have been referred to as the "resistant minority," so that in order to completely render water sterile it would be necessary to use large quantities of copper, — quan- tities so large, in fact, as to be objectionable. In large supplies, furthermore, there is difficulty in applying the chemical so as to properly distribute it through the water. AMiile disinfection of the supply might do some good, yet, taking everything into consideration, there is probably no better temporar}^ expedient that can be adopted than to thoroughly boil the water before it is used, at the same time taking steps to decrease its use by providing for a house-to-house delivery of pure water. Filtration of water, while an adequate remedy, cannot often be undertaken as an emergency measure, although under some conditions this might be done. It often happens, however, that a typhoid epidemic that has been caused by an infected water makes such an impression on the community that filtration, or the adoption of a new supply, soon follows. To control an epidemic and keep it within bounds demands prompt and energetic measures. An epidemic is almost sure to bring to light any weak spots in the sanitary conditions of a city. It must be remembered that there is a difference between contamination and infection. A contaminated well water may be used for years without causing typhoid fever, but during an epi- 226 TYPHOID FEVER. demic it may become infected as well as contaminated, as in the case of the Barnes well at Ithaca. Many other forms of uncleanliness which ordinarily cause no serious trouble may, at a time of an epidemic, be the means of spreading the disease. Hence, the presence of typhoid fever in epidemic form in a community demands not only the removal of the orignal cause, but a wholesale house cleaning, and the institution of far-reaching sanitary reforms. Besides taking measures to rid the city of all that might tend to spread the disease through secondary infection, it may be necessary to take extraordinary measures to secure adequate services for the sick. It may be necessary to bring in extra physicians and nurses from outside, to establish a temporary hospital for those who cannot be well treated in their homes, to supply freely large quantities of simple disinfectants, and to make many blood tests of suspected cases. During a general epidemic the importance of isolation becomes greatly increased, as the disease is likely to take greatest root among the poorer classes of population where con- tagion cannot be easily prevented. Hence the question of hospital service at such times becomes one of para- mount importance. The board of health should have the power to remove patients to the hospital if they cannot be treated in their homes without danger to others. Through it all, a "safe and sane policy" should be consistently pursued. A community afiflicted with a typhoid fever epidemic is sometimes almost panic- stricken. Correspondents may fill the public press with CONTROL OF TYPHOID FEVER EPIDEMICS. 227 their theories, and many foolish things may be said and done. What is needed is a strong central authority that for a time can exercise almost autocratic power, and a government and a public opinion that will uphold such authority, and provide all necessary resources. Fortunate, indeed, is the city that has a health officer or health department equipped for such an emergency and a government that will rise to the occasion. CHAPTER X. THE INFLUENCE OF PUBLIC WATER-SUPPLIES ON THE TYPHOID FEVER DEATH-RATES OF CITIES. The manner in which the sanitary quality of public water-supplies influences the typhoid fever death-rates of cities, has been sufficiently discussed. It remains to study the magnitude of this influence. The relation between the two is so close that the typhoid death-rate has been often used as an index of the quality of the water. Generally speaking, it is safe to do this ; a very low death-rate indicates a pure water, and a very high rate, a contaminated water. Between the two extremes there is a range of death-rates from which the quality of the water cannot be predicted, and the aid of other data has to be invoked. But, taking the death-rates of a city for a term of years, and studying their seasonal and annual variations and their general average, one can form a pretty sound conclusion as to the sanitary quality of the public water-supply. In his valuable little book on "Water and Public Health," published in 1897, Mr. James H. Fuertes, C. E., gave a series of diagrams in which the relation between typhoid death-rates and various water-supplies, grouped according to the character of their source, was strikingly shown. These diagrams, although based upon data ten 228 INFLUENXE OF PUBLIC WATER-SUPPLIES. 229 years old, are just as applicable to-day as they were then. One of them is reproduced in Fig. 24. It shows the range within which 75 per cent of the death-rates fell for each kind of water-supply, and may be considered as marking the ordinar}- limits for each group, although extreme figures both above and below those given were not uncommon. 100 80 CO a: LU 1- fe ^ < Q LU Q 2 a z Q. s S60 ui40 I- < 20 m ^ Fig. 24. Diagram Showing tlie Relation bet-ween the Character of Water-supphes and Typhoid Fever Death-rates. (After Fuertes.) Spring waters, well waters, and filtered surface waters are generally considered as safe sources of supply, and the diagram shows that for these groups the death-rates range from about 5 to 25 per 100,000, the average being 230 TYPHOID FEVER. somewhere between 15 and 20. Supplies from upland streams, impounding reservoirs, and from large lakes and rivers, are insecure in quality; and the corresponding death-rates range from about 15 to about 55, and average about 35 per 100,000. Supplies which are conspicuously contaminated may have death-rates anywhere from 40 up to 100 or more. No hard and fast lines can be drawn between the different groups, as the potency of other causes than water has to be considered in each case, DEATH-RATE PER 100,000 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 ! 1 1 1 1 uncontXminated public water su 'PLIES ^ -^ A CO ■ITAN UNA! ED F UBLK 5 WATER 3UPP JES '^ m^. ^^ 5^?^ ^5^ ^^ ;^^ 5^^ 'm^ ■<^, ^^ m>. ;^^ ^ ^?^ Fig. 25. Diagram Showing the Ordinary Range of Typhoid Fever Death-rates in Cities having Contaminated and Uncontaminated Water-supplies. but it is commonly assumed that in the northern parts of the United States a continued typhoid death-rate above 20 per 100,000 indicates that the public water-supply is of questionable purity, while a continued death-rate below 15 indicates safety. In the Southern states the dividing lines would have to be placed at a somewhat higher figure, as the influence of other factors is greater. If a good water-supply means a low death-rate, and a bad water-supply means a high death-rate, one would INFLUENCE OF PUBLIC WATER-SUPPLIES. 231 expect to find that when a city changed its supply from a polluted river to that of driven wells, or constructed filters to purify a contaminated water, this would be followed by a lessened prevalence of typhoid fever. This is just what has been happening on all sides during the last two decades, and it is to improved water-supplies more than to anything else that the recent reductions in typhoid fever have been due. A few examples will sufficiently illustrate this: Cities which have changed their Source of Supply. Frankfort-on-the-Main, Germany. Frankfort-on-the Main introduced a public water-supply in 1872. Prior to that, there had been no general supply, and private i 1 [ [ 1 1 If ' ' '" "-'---^^ M 1 1 1 t [ 1 1 r , ■ • : i 1 1 1 1 1 ) i ■ ' . '~0\ 1 { 1 Mi!'' \ ■ , . 1 : \\ : ! 1 1 1 i 1 ' ' * 1 ' ■ _ \ ~ "•'•' "5^ ' 1 ! "it X ID ! Mi ~ ; 1 ^if,-i*'?.. 1 i 1 ^! H "I r ; \ N^-: ( ' 1 ! Lf ' ' t -1 1 1 t ' '"■^, - >—* ' ■■ „ . ■ .1— , J— f ' ' 1 ' < i 1 , - — ....^IJ^-^^^— . j r^ ■' ■' 1 1 '— 1 ' -J ■ '■ ■ -■----- L^ ■ U ill - . L_P-l-r-^-l— , ,, |j 1 ' ' ' ' 1 -■- :.;:.; i_H-:--j-i_(7^ i to O C- iC CI o - Fig. 26. The Curves Marked " Sewers " and " Water " Show the Percentage of Houses Joined to the Sewers and Water Mains, Frankfort-on-the- Main, Germany. (After Fuertes.) weUs had been the only source. W. H. Lindley, C.E., has shown the effect of this new supply on the health of the city by a diagram (Fig. 26) which is self- explanatory. 232 TYPHOID FEVER. Newark, NJ. In 1892, Newark, N.J. changed its source of water-supply from the polluted Passaic River to the Pequannock River, an upland supply, utilized by the construction of a series of large impounding reservoirs. 120 100 §80 O £ 60 a. I 40 i 220 ^ N n ra RK, N J. 1 ^ P ^ m * PA ISA C R IVE ! W Ml Rl SEC FC RA SH 5R1 TIME - ^ 'A M b u Z'. : L- , ■■■■■'■' 1 ^/? '-yx ^ ^ ^ PASSAIC RIVErI 1 PEQUANNOCK RIVER '<^ J^ '■- Mill! I 1 III 00 oc CO CO eg CO 00 CO S2 CO oc oc a CC oc 00 CO CO 00 a CC 00 CD CO ot 01 a CO CO cn 00 LO cn CO CO 01 00 1^ 00 00 00 en 00 01 cn CO z 01 10 cn U3 cn r- Fig. 27. Diagram Showing the Relation between the Public Water-supply and the Typhoid Fever Death-rates in Newark, N.J. The population on this watershed is sparse; there are no large towns on it, and the drainage of the individual houses near the tributary streams is carefully looked after. The change in the typhoid death-rate resulting from the use of this better water is shown in Fig. 27. In February, 1899, during a spell of very cold weather, a water famine was threatened and it became necessary to augment the supply by pumping water from the old Passaic River supply into the low service system. This was done for about a week, and resulted in about four ixfllenxe of public water-supplies. 233 hundred cases of typhoid fever and about fifty deaths, — practically all of them within the low service district. Jersey City. During the last ten or fifteen years Jersey City has had four different sources of water-supply. For some time prior to 1896 the water was taken from NEAR THE CITY RIVER AT LITTLE FALLS Fig. 28. Diagram Shov,-ing the Relation between the Water-supply and the Typhoid Death-rates in Jersey City, X. J. the Passaic River at Belleville, near the city, at a point where it was considerably polluted. Since 1896 the supply has been taken from three upland sources. Between 1896 and 1901 the Pequannock water was used; between 1901 and 1904 the supply was obtained from the 234 TYPHOID FEVER. Passaic River at Little Falls. Since then, the Rockaway River water from the Boonton reservoir has been used. In no case has the water been filtered. The diagram shows that since the abandonment of the Passaic River 170 .160 150 ^140 8130 §120 alio SlOO ^ 90 < 80 I 70 < 60 111 o 50 %'' X 30 ^ 20 10 m m. y/} rrr /// Va '// ' LOVVELL 1 — M AS 3. ' 'V/ -T- u ' ! — 1 --I— r— , ; Y' 1 ; " i i ; i i ' i ' ^ :!'';'! .. ■ ' ' ' • I ■ ' ' '' ^ ^77? 777/ -m S3 — — r ' \'i \ : .' r\" • I ' . ' ' --\'-- -+— 1 M ER ^IIV AC RIVE \ V VA1 •EF G RO JN 3 V VA" rEF i m^4r\ l,i 1 'ly/. m 1 M ^ 1 1 1 _ UNFILTERED Fig. 29. supply the typhoid fever death-rate in the city has been lower than formerly, although there was an outbreak in 1898 which was due to a temporary return to the old Passaic River supply. Except for this year the fluctua- tions in the typhoid fever death-rate of the city have not been large. The Rockaway source, however, is not as safe as the other upland sources, and since its use there has been a slight increase in typhoid fever in the city. TXFLUE^XE OF PUBLIC WATER-SUPPLIES. 235 Cleveland, Ohio. The city of Cleveland takes its water-supply from Lake Erie. Prior to 1904 the point of intake was only 1.5 miles from the shore, and was subject to occasional severe contamination from the city's sewage; but in the year mentioned a new intake was put in service, and the water is now taken at a distance of four miles from the city. The change in the supply resulted in an immediate reduction in the typhoid death-rate. This has been already referred to. (See Fig. 18, p. 171. J Lowell, Mass. Profiting by the lesson of the epidemics of 1890 and 1892, the city of Lowell, in 1896, abandoned the use of the polluted ]\Ierrimac River and obtained a supply from driven wells. The change to the new supply was somewhat gradual, and the reduction in the death- rate was correspondingly gradual. Cities li'Jdch retained their Old Supplies, hut Constructed Filters. Zurich, Switzerland. The water-supply is taken from Lake Zurich, near the outlet, not far from the heart of the city. Xo public sewers discharge into the lake, but the water is necessarily more or less pol- luted. Prior to 1886 the typhoid fever death-rate in the city had been high, but in that year new filters were constructed and this immediately reduced the rate to a low figure. Hamburg, Germany. Hamburg is chiefly famous among sanitarians for the great cholera epidemic of 1892. At that time filters were under construction for the purification of the water-supply, which was 236 TYPHOID FEVER. taken from the Elbe River. The works were con- structed in 1893, and since then the health of the city has greatly improved. 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 m mww/M m ZURICH, SWITZERLAND, c. OLD FILTERS NEW FILTERS Fig. 30. Lawrence, Mass. Taught by the sad experience of several epidemics, the city of Lawrence constructed a filter plant in 1893. This city has the distinction of being the first in this country to take up filtration INFLUENCE OF PUBLIC WATER-SUPPLIES. 237 UNFILTERED FILTERED Fig. 31. Diagram Showing the Relation between the Water-supply and the Typhoid Death-rates of Hamburg, Germany. CM CO ^ 10 (o r« Fig. 32. 238 TYPHOID FEVER. along modern lines, and the credit belongs to the Mas- sachusetts State Board of Health. The particular type of the filter resulted from the experiments made at the world-renowned Lawrence Experiment Station, with which some of the best-known American sanitary engi- neers have been connected. The construction of this filter brought an immediate reduction in the typhoid fever death-rate. The filter gradually became outgrown, however, and its efficiency correspondingly decreased. At the present time (1908) it is being enlarged. The original Lawrence filter differed from those which have since been built. Among other things, it had no roof, and in consequence there has been more or less trouble in cleaning the sand beds in the winter on account of ice. The filter was designed also to operate inter- mittently instead of continuously. Albany, N.Y. The filter at Albany, constructed in 1889 to purify the water of the Hudson River, polluted by the sewage of Troy, Cohoes, Schenectady, and many other cities, represents the type of filter which has since been largely used in this country. It followed European practice more closely than that at Lawrence. It is a "sand filter," or a "slow sand filter," as it is often called, and consists of a large area of sand four feet deep which rests on a foundation of gravel and coarse stones, embedded in which are collecting drains. This sand area, which covers 5.6 acres, is divided into several "beds," which may be separately controlled. The filter material rests on a concrete floor, and is covered with a groined arch roof, supported on piers INFLUENCE OF PUBLIC WATER-SUPPLIES. 239 which pass down through the sand bed. The river water, after first passing through a large settling basin, UNFILTERED FILTERED ©4 C3 ■* 10 «o r» Fig. 33- Diagram Showing the Relation between the Water-supply and the Typhoid Death-rates of Albany, N.Y. flows over the sand, filters down through it at a slow rate, and collects in the underdrains. The process 240 TYPHOID FEVER. removes, on an average, something like 99 per cent of the bacteria, and any typhoid germs present are pre- sumably removed in the same proportion. 100 80 60 40 20 i i i ^ #^P-^ BINGHAIV1T0N,N.Y. Y 9-/y/'y ^\^', v//' SUSQUEHANNA RIVER WATER I r_i UN FILTER ED //>/-'/^///.A'//y 1 U> h-.COOlo'-PJW* -to <£> h- " 00 o OJ " CO . ,"!^ 10 (O t~ Fig. 34. Diagram Showing tlie Relation between tlie Water-supply and the Typhoid Fever Death-rates of Binghamton, N.Y. When the people of Albany drank the Hudson River water raw, typhoid fever was rampant; but the filter put a stop to this, and caused a very sudden drop in the death- rate. This filter is now working up to its capacity, and alterations are being made with the object of increasing its output. In considering the typhoid death-rate since 1900, it ought to be noted that the filtered Hudson River water does not furnish the entire supply of the city. Part of the water used is taken from a surface supply IXFLUENXE OF PUBLIC WATER-SUPPLIES. 24 1 *io^r~-QOCT>gr-c-inTfintD 200 180 160 140 H 100 iS 80 40 20 W^ I WATERTOWN, -^^ N.Y. ^^ WW^: BLACK RIVER WATER .//^., , '-'Ya UN FILTERED FILTERED Fig. 35. Diagram Sho-wing the Relation bet-n-een the Public Water-supply the Typhoid Death-rates in Watertown, X.Y. and 242 . TYPHOID FEVER. which is not fihered, and the sanitary quality of which is not secure. Binghamton, N.Y. The water-supply of Bingham- ton, N.Y., is taken from the Susquehanna River and is used without any storage whatever. The water is often muddy and, worse than this, it is contaminated. In 1902 a filter plant was constructed. It is of the mechanical type, using alum as a coagulant. Almost immediately after this installation there was a decided decrease in the amount of typhoid fever, as well as of winter cholera, which up to that time had been quite prevalent. During the last four or five years the typhoid fever rate has been exceptionally low. Watertown, N.Y. Watertown takes its water-supply from the Black River, a stream which is considerably polluted by paper-mill refuse, and with the sewage of several large communities. For many years the typhoid fever rate was high, and some years it was exces- sively high. During 1904 there was a severe epidemic during which about six hundred people were made ill and nearly fifty people died. A iilter plant was under construction when this epidemic occurred, but it was not put in service until September, 1904. Since then the typhoid fever death-rate has been very much lower. Paterson, N.J. Paterson, N.J., is one of a group of communities supplied with water by the East River Water Company. The source of the supply is the Passaic River at Little Falls. Until 1902, it was used without filtration, but during that year a mechanical filter was put in service, and since then the typhoid fever IXFLUENXE OF PUBLIC WATER-SUPPLIES. 243 rate has been much lower. The other communities supplied by the same company show corresponding reductions in the typhoid fever death-rates. FILTERED cj CO •* 10 o r^ Fig. 36. Diagram Showing the Relation between the Water-supply and the T}-phoid Death-rates of Paterson, N.J. Paris, France. Filtered water has been recently introduced into one of the suburbs of Paris. Fig. 37 illustrates the improvements in the typhoid fever death- rates that have been produced by it. Until within a comparatively recent period French sanitary engineers have favored ground water rather than liltered water, but recently there has been a changing sentiment and the tendency now is towards the greater use of filtration. St. Louis, Mo. The water-supply of St. Louis is taken from the Mississippi River, just below where the Missouri 244 TYPHOID FEVER, enters. The water is intensely muddy at times, and is never clear. Mark Twain or some one else once said that TYPHOID MORBIDITY PER 100,000 TYPHOID MORTALITY PER 100,000 I I il J J 4 1 Si s| - I i < « I il il J 1 ^ i I i_i si si il ;;: qI 2 s| ^ il ^ ^1 Fig. 37. Effect of Filtration in Reducing the Typhoid Fever Death-rates and the General Mortality in a Suburb of Paris. (After Chabal.) when the wind blew over the water it raised a dust. The water is not filtered, but for many years has been passed through settling basins, where 8o or 90 per cent INFLUENCE OF PUBLIC WATER-SUPPLIES. 245 of the mud was removed. In 1904 this process of sedi- mentation was rendered somewhat more efficient by adding two chemicals to the water before it entered the basins, namely, sulphate of iron (copperas) and lime. O r- ct ooG 360,000 560,000 None 275,000 1,500,000 2,600,000 None 30,000 310,000 1,860,000 3,160,000 0.23 1-45 6-3 9-7 Even to-day these figures are out of date, and the pro- portion of the population supphed with filtered water, or contemplating the early adoption of filtration, is greater than that given. This movement is bound to go on until every city has either a ground water naturally filtered, or a surface water artificially filtered. Clean 248 TYPHOID FEVER. and wholesome water every self-respecting municipality is bound to have.^ Cities where the Introduction of Filters has not been Fol- lowed by a Material Reduction in the Typhoid Fever Death-rate. Youngstown, Ohio. The water-supply at Youngs- town is taken from the Mahoning River. While origi- nally of fairly satisfactory quality, its pollution gradually increased and gave rise to a steadily increasing typhoid fever death-rate in the city. In August, 1905, a mechani- cal filter was introduced. This lowered the rate some- what, but not as much as was expected. An outbreak occurred during the early part of 1906, which was studied carefully by Mr. Paul Hansen for the Ohio State Board of Health. He found that out of 153 cases contracted in the city, 93 resided in houses where there were no sewers and no public water-supply, while 109 claimed to have used well water only. Many of the houses were in a poor sanitary condition. Investigation showed that this outbreak was not due to the use of the city water, then being filtered, but rather to the use of polluted wells, and to direct contact, including transmission by flies. In 1907 the disease was less prevalent. Washington, D.C. The city of Washington takes its water-supply from the Potomac River at Great Falls, about 14 miles above the city. For many years it passed through two reservoirs, the Dalecarlia and the George- * Readers interested in the problems of public water-supply should consult Mr. Hazen's recent book on " Clean Water and How to Get it." INFLUENCE OF PUBLIC WATER-SUPPLIES. 249 iot0h-esnov^cQ eo-^-iDtoK UNFILTE-aED FILTERED Fig. 40. Diagram Showing the Relation between the PubHc Water-supply and the Typhoid Fever Death-rates in Youngstown, Ohio. 250 TYPHOID FEVER. INFLUENCE OF PUBLIC WATER-SUPPLIES. 251 town Reservoir. In 1902 a third reservoir and settling basin, known as the Washington City Reservoir, was put in service. In October, 1905, a filtration plant of the most modern construction was put in operation, so that at the present time the Potomac water passes through three settling basins and a filter before it is delivered to the consumers. For many years the typhoid fever death-rate in Wash- ington had been high, and it was confidently expected that after the introduction of filtered water the rate would materially decrease. During 1906, however, the death- rate increased slightly instead of decreasing. As it did not seem possible that the filter could be at fault, an extensive investigation of the subject was undertaken by a commission consisting of Dr. M. J. Rosenau, L. L. Lumsden, and Joseph H. Kastle. A voluminous report was published in 1907 which in some respects is one of the most instructive reports on the subject of typhoid fever that has appeared in recent years. Although this investigation was most exhaustive, yet the data collected failed to establish the cause of the greater part of the cases which occurred in the city. Indications pointed strongly, however, to milk as being the chief source of the infection, and this was emphasized by Professor Sedgwick, and Mr. Theodore Horton, who also investi- gated the prevalence of the fever. Looking back over the history of typhoid fever in Washington the data seem to indicate that not for many years has the water-supply played the major part in the causation of this disease, for it had been already sub- jected to a partial purification, namely, that due to 252 TYPHOID FEVER. sedimentation and storage in the three reservoirs. From 1897 up to 1902, when the Washington City Reservoir was buik, the typhoid fever rate had been gradually increasing, especially during the winter months, but between 1902 and 1905 there was a falling off in the rate which may be attributed in part, at least, to the greater purification brought about by the increasing use of the additional sedimentation. If, then, the water had played but little part in the causation of the disease before the filter was con- structed, it could not be expected that the operation of the filter would result in any material reduction in the death-rate. A study of the seasonal distribution of typhoid fever in Washington shows that the disease is chiefly one of summer, and that it has not for many years been preva- lent to a considerable extent in the winter and spring. This fact, taken in connection with an abnormally large proportion of cases among children, points to the impor- tant influence of milk and direct contagion in the spread of the disease in that city. During the summer of 1907 there was a decrease in the amount of typhoid fever in Washington, due, in part, no doubt to the activities resulting from the investigation referred to. Cities which have made Slight Changes in the Character of their Water-Supplies. Boston, Mass. For many years Boston's water-supply was derived from the Sudbury and Cochituate water- sheds. These sources, while subject to considerable pollution, had been carefully treated, the sewage of INFLUENCE OF PUBLIC WATER-SUPPLIES. 253 several large communities had been diverted, filter beds had been built to purify the water of certain contami- Nouvnn^od r -o m aaA3si QioHdAJ. woad sHivaa do uaawoN Q nated brooks, cesspools and privy nuisances adjacent to the streams had been abated, and a careful patrol 2 54 TYPHOID FEVER. maintained. Yet the population was there. It was 776 per square mile on the Sudbury systems, and 282 per square mile in the Cochituate system, so that in spite of the sanitary reforms and the natural benefits of the large storage reservoirs the typhoid fever death-rate in Boston was not as low as it should be. In 1898 the new supply from the Nashua River, impounded in the great Wachusett Reservoir, was intro- duced. The Nashua watershed is much less populated than the Sudbury and Cochituate areas, — the number of inhabitants per square mile being only 49. The storage in the reservoir is also longer. Since this new supply has been in use there has been a gradual drop in the typhoid death-rates which may be attributed, in part at least, to the use of better water. As the new supply yields a water less colored and less affected with odors due to alg£e, it has been used to the partial ex- clusion of the old sources.^ When the consumption increases, however, so that it is necessary to once again draw heavily on the old supplies, and this must happen some time, it will be surprising if the people of Boston remain content to be served with water without filtration. Boston has been for many years a leader in sanitary reforms; it is not likely that she will allow herself to be outstripped by the other large cities in the protection of her water-supply. New York City. New York City has been for many years supplied with water from the Croton River. At first there was a single reservoir known as the Old Croton * During the last few years the Wachusett Reservoir has furnished about two-thirds of the supply. INFLUENCE OF PUBLIC WATER-SUPPLIES. 255 Lake. Now there are a dozen or so reservoirs on the various tributary streams, and the Old Croton Lake has Noiivmdod 9061 0681 9881 0881 9Z.81 0^81. U (U o > >i •S c fH D HHABd QioHdAx lAioud sHiV3a do aaawfiN been lost in the new reservoir created by the construction of the great dam. While the general source remains the 256 TYPHOID FEVER. same throughout, the methods of utilizing the water have been subject to change. A study of the typhoid fever death-rates of the city is interesting in several respects. In 1 869-1 870 there were severe droughts during which the rate was high. From that time the rate fell gradu- ally to 1879. Then followed some very dry years during which the typhoid fever rate increased materially. Be- tween 1883 and 1897 the rate steadily decreased. This may be attributed to the constantly increasing storage capacity, to the generally more favorable meteorological condition, but especially to the expedients adopted to protect the water-supply from pollution. In 1888 the board of health established rules and regulations relating to the pollution of the watershed, and in 1893 expensive purchases of land and buildings were made along the courses of the streams and around the reser- voirs. In 1893 a sewage purification plant was estab- lished on the watershed at Brewster. The increase in 1898 was due to the soldiers returning from Cuba after the Spanish War. During the last few years there has been a further slight reduction in the death-rate, which may be due in part to the greater care exercised in pre- venting contamination from small sources. It must be remembered, that in a great city like New York, many causes of typhoid fever are in operation, and these are difficult to trace. Nevertheless, the fluctuations in the typhoid fever curve do appear to reflect to some extent the sanitary quality of the public water-supply. Brooklyn, N.Y. The water-supply of Brooklyn is taken from Long Island, partly from driven wells and INFLUENCE OF PUBLIC WATER-SUPPLIES. 257 506 L 0061 S68I. 0681 9881 0881 3^81. 0Z81. NOIlVnndOd S s ° ■■ Q > u c § p ■* ■^ > a) 2 t^ § * S IS a3A3j aioHdAx woHd SHivHO do aaawnN partly from small streams. Twenty years ago the greater part of the water was surface water; to-day the larger portion is ground water. For a generation the typhoid fever death-rate in 258 TYPHOID FEVER. Brooklyn has fluctuated between comparatively narrow- limits and has shown much smaller fluctuations than in most of the cities of the country. It has also been com- paratively low. Nevertheless a study of the fluctuations in these rates seems to correspond with the changes which have been made in the source of water-supply. Between 1870 and 1880 the death-rate gradually fell, probably because during this time hundreds of polluted wells throughout the city were closed by order of the board of health. Between 1880 and 1890 the rate increased. During this time the draft upon the water- shed was constantly increasing, while certain streams somewhat more polluted than those previously in use were added to the supply. From 1890 to 1895 the rate dropped again. Several causes probably contributed to this decrease. The new watershed, first drawn upon in 1 89 1, added a considerable volume of relatively pure water to the supply; in 1892 the Ridgwood Reservoir was enlarged, while during the years 1893-5 arrangements were made for panning the water-closets in the village of Hempstead along one of the important streams. About that time also some of the more polluted sources near the city were cut off. The increase in 1898 was due to the Spanish War and the further increase in the next few years was due proba- bly to the greater draft upon the watershed. Recently the rate has been falling slightly, and this decrease has been coincident with the establishment of several small filter plants to purify the most threatened surface waters and the addition of new sources of ground water. INFLUENCE OF PUBLIC WATER-SUPPLIES. 259 Baltimore, Md. The water-supply of Baltimore is impounded surface water used without filtration. The drainage area is about 350 square miles and the popu- lation upon it about 32 per square mile. A thorough system of sanitary control is said to be in force. The 500,000 400,000 300,000 200,000 a. 100,000 Fig. 45. Diagram Showing the Number of Deaths from Typhoid Fever and the Corresponding Death-rates for Baltimore, Md. city has no general sewerage system for house drainage: slops for kitchen, bath-tubs and laundry waste flow in gutters all over the city, and the night soil from thous- ands of cess pools is carried in scows and teams to truck farms and used on gardens. 260 TYPHOID FEVER. Under these circumstances the typhoid fever situa- tion in the city is much better than one might expect. Cities Supplied with Water Imperfectly Filtered. If a fiher is to give good service and so purify the water that the public will be adequately protected, it must be properly designed and properly operated. A good many illustrations might be mentioned of filters which have failed to do the work expected of them and the recital of these failures has sometimes led unthinking people to believe that all filtration was unsafe. But it must be remembered that there are filters and filters. Safety clutches on elevators sometimes fail to work, yet safety clutches are a good thing. Many of the early mechanical filters were filters only in name; they strained the water, but did not to any great extent remove objects of microscopic size, — con- sequently they were not able to remove the typhoid bacilli, or to render an infected water safe. Filters of this kind were in use at Augusta and at Bangor, Maine, during the epidemics there. The first sand filters built in this country were those at Poughkeepsie and Hudson, N.Y. They did good service for many years, but they became outgrown in size, and the pollution of the Hudson River became greater than they could manage, as constructed, so there came a time when as a sanitary safeguard they were not a complete success. When the flood of typhoid fever came down the valley in 1892, both of these cities suffered, but they undoubtedly suffered far less than INFLUENCE OF PUBLIC WATER-SUPPLIES. 26 1 they would have if no fiher at all had been in use. These filters have since been reconstructed and at Pough- keepsie a new sedimentation basin has been recently built. Like all other structures, filters may deteriorate, parts may wear out, and they may become outgrown. Some- times these repairs and enlargements are made too late. The filter at Lawrence was outgrown for many years before additions were made. There are many old-type filter plants in the country to-day which ought to be over-hauled, or replaced by modem structures. In building filters it pays to build well. A plant suited to the local conditions will do better work and last longer than the filters of stock pattern, of which so many were ■put in a few years ago. Lorain, Ohio. The water-supply of Lorain is taken from Lake Erie at a point where it is considerably polluted by the sewage of the city, which it receives through the Black River. In 1899 a mechanical filter was put in, and for a few years alum was used as the coagulant. Then, in order to reduce expenses, an iron sulphite process was tried. This was found to be unsatisfactor}% and during its use the strainer system of the filter was practically destroyed by the action of this chemical. Since 1903, iron sulphate (copperas) and lime have been used. Before the introduction of the filtered water the typhoid fever death-rates were very high; they fell at once on the introduction of the filter, and remained low for the first few years of its operation. When the filter got out of repair, by reason of the damaging effect of the iron 262 TYPHOID FEVER. o> o»-e4W'r>n o»-M«»i'io«ot^ LOR A 160 140 120 oi 100 UJ ^ 60 N, OHIO 1 #^. r^^T^ 'm 40 ^ 20 I t — ^ y/// ///{^//// m^ LAKE ERIE -UNFILTERED- ALUM PROCESS IRON IRON SULPHITE SULPHATE & LIME Fig. 46. Diagram Showing the Relation between the Water-supply and the Typhoid Fever Death-rate in Lorain, Ohio. sulphite process, the typhoid fever death-rate in the city rose; but recently with somewhat more careful operation the rate has fallen, even though the filter has been INFLUENCE OF PUBLIC WATER-SUPPLIES. 263 much overworked on account of the rapidly increasing population. These records are interesting as showing the effect of faulty operation of a filter plant on the health of the city. Lorain has recently constructed a new filter. Stream Pollution and Typhoid Fever. Typhoid fever often sweeps down a river valley as a sort of wave. A number of instances of this have been already cited. On the Penobscot River the Millinocket epidemic so infected the water that the fever broke out at Oldtown, Brewer and Bangor. On the Kennebec River the Waterville epidemic caused several hundred cases in Augusta and Richmond. On the Merrimac River the disease spread from Lowell to Lawrence and Newburyport. Perhaps one of the most striking examples of the infection of a river valley is that of the Hudson River and its tributaries. Good water-power sites caused the early development of many large communities along these streams, and naturally these cities and towns emptied their sewage into the rivers as the most convenient places of disposal. Unfortunately, some of the com- munities lower down used the water for drinking and without filtration. The experience of Albany has been referred to. Typhoid fever raged there until the filter was built. It will be interesting to note the death-rates of some of the other cities along these streams. Fig. 47 shows how the epidemic which occurred in Schenectady in 1890-92 affected the cities dowm the valley. At that time Albany had no filter plant, and those at 400 U u Q 2 u Pi rt 1890 1894 264 INFLUENCE OF PUBLIC WATER-SUPPLIES. 265 Hudson and Poughkeepsie were old and imperfect in operation. A study of the records of the New York State Depart- ment of Health reveals the presence of an exceptional amount of typhoid fever in the Hudson Valley region as compared with other regions. In general the death- rate is about twice as high as that for the entire state. Many other river valleys are likewise overrun with typhoid fever, — the Susquehanna River, the Potomac River, the Ohio River, the Mississippi River, etc. These waves of typhoid fever which pass down a river valley are, of course, due in the main to the water car- riage of the bacilli; but it is conceivable that there may be other modes of transmission, and that the disease may follow the general trend of the lines of travel, just as Asiatic cholera used to follow the oriental caravans and sweep westward from Asia across the continent of Europe. In seeking to prevent this spread of typhoid fever by rivers, the question has been raised in a number of places as to whether it is better to purify the sewage of an upper city on some river or to filter the water of a lower city. The answer is, — both are desirable and in the course of time both are destined to take place. But, except in a few instances, both are not now needed. It is generally much cheaper to filter the water below than it is to purify the sewage above, and in the present state of the art it is also more efficient. In general, water filtration should come first. Later, when the load is greater than the filters can safely bear, works for the purification of the sewage should be installed, or else 266 TYPHOID FEVER. double filtration of the water required. What is best to do must depend upon the peculiar circumstances of each case. The direct pollution of streams by mills and factories, so located that fecal matter from privies and water-clos- ets finds direct access to the water, is a particularly dan- gerous form of contamination. Several epidemics have arisen from such cases, as for example, in Lowell, Mass., and, probably, Watertown, N.Y. Stream pollution has another side, however, namely, the nuisances to which the disposal of sewage gives rise, and these, taken in connection with sanitary considera- tions, are going to result in the establishment of many sewage purification plants along our lakes and streams. Unquestionably many American streams are being rapidly spoiled, and before it is too late much energetic work ought to be done to prevent this. Stream pollu- tion is the result of the prosperity of our cities, but if by increasing our capital in the form of mills and factories, we decrease it in the form of natural water resources, we are not, as a nation, growing rich as rapidly as we think. The writer is not unaware that in some cases water- supplies have been taken from contaminated sources and used for many years with no apparent serious effect on the public health ; and he is not unaware that some engi- neers, and even some physicians, still hold to the old theory that running water purifies itself to an extent that is sufficient for practical purposes. He has not failed to consider this negative evidence, but in spite of it he holds, as do the majority of sanitary engineers to-day, that water once contaminated is always dangerous until purified. CHAPTER XI. THE EFFECT OF MILK-SUPPLIES ON THE TYPHOID FEVER DEATH-RATES OF CITIES. This chapter must be short, as the data for a fair discussion of the subject have not yet been collected. It is one of the problems for the sanitarians of to-day to work out. Up to the present time there are very few, if any, American cities provided with a thor- oughly safe and wholesome milk-supply. Pasteuriza- tion or sterilization have not become general, although the public conscience is becoming awakened to the need of some such general treatment. The relative merits of the inspection of the milk farms and the general pasteurization of the milk-supply is being much discussed nowadays. It is argued, on the one hand, that pasteurization is inefficient as ordinarily carried on, that it renders milk less easily digested and that, by destroying certain natural germicidal properties of the milk by heating, it reduces its keeping qualities and renders a subsequent infection more dangerous; and it is argued, on the other hand, that inspection cannot guarantee against infection, that pasteurization can be made efficient, and that the germs of typhoid and the non-sporing bacteria, at least, will not subsequently develop after pasteurization. It is not necessary to 267 268 TYPHOID FEVER. recite here all the arguments, scientific and commercial, that have been made, for the subject is one upon which the requisite data have not all been obtained. There are many aspects of the milk question. Typhoid fever is not the only disease involved. Milk may be the means of transmitting scarlet fever, diphtheria, tuberculosis, and other diseases. Dirty milk, even when not directly infected with specific bacteria from some previous case of disease, may produce serious intestinal disorders in bottle-fed infants, — and this may be due simply to a disregard of ordinary cleanliness in the handling of the milk and in the treatment of the milk bottles. It may be too early to prophesy, but in the author's view the solution of the milk question will finally be that in srnall communities, where there are personal relations between producer and consumer, pasteurization will not be needed, but that in large communities, where there can be no such personal relation, pasteurization or its equivalent will be looked upon as the only safe- guard, and will be made compulsory by law. But even with pasteurization required, the inspection of the farms will still be needed. As in the case of water-supplies future sanitarians will demand a clean watershed and then filtration, so in the case of milk-supplies, they will insist upon clean farms and pasteurization. The advantages of pasteurization are slowly, but surely, being manifested by experience. Some interest- ing examples are certain cities of England and Scotland. The diagram (Fig. 48) shows that in Glasgow there has been a marked reduction in typhoid fever during the last three years. This cannot be accounted for by EFFECT OF MILK-SUPPLIES. 269 any change in the water-supply, for there has been no change, and the supply is taken from Loch Katrine and NOT PASTEURIZED PASTEURIZED IN PART 00 CT> Fig. 48. is considered to be of excellent quality. About three or four years ago, however, they began a practice of pas- 2/0 TYPHOID FEVEk. teurizing much of the milk sold in the public shops, and this in a great measure is thought to account for the decrease, although it cannot be considered as the only- cause. During the last three or four years there has been a decrease in the amount of enteric fever in Liverpool, although at no time during the last ten years has the rate been excessive. The decrease is probably due in part to improvements which have been made on the water-supply watershed and to greater care regarding the use of oysters, but very largely to the increased use of pasteurized milk. The improvements in the water- shed have consisted of the purchase and reforesting of large areas, and the improvement of the sanitary conditions on the farms purchased. The water-supply is filtered. There are now six depots for the sale of steriHzed and modified milk. These were established in 1 901, and a study of the typhoid statistics of the city shows that the decrease in the death-rate began after 1902. During the last three years the general death- rate among the infants supplied from these depots was about 96 per 1000 as against 171 per 1000 for the entire city. Another instance of the benefits of pasteurization is that of a certain milkman in Washington, D.C., referred to in the report on the Origin and Prevalence of Typhoid Fever in the District of Columbia in 1906. This dealer sterilized all of his milk bottles and pasteurized all of his milk, and it was noticed that of the large dealers he had the smallest number of typhoid fever cases among his customers in proportion to the milk sold. A com- EFFECT OF MILK-SUPPLIES. 271 parison of his record with that of the other milk dealers in the city who did not sell pasteurized milk is shown by the following figures: Dairy. Gallons of Milk Sold During July, August, September and Octo- ber, 1906. Number of Cases of Typhoid Fever Dur- ing July, August, September and October, 1906. Number of Cases of Typhoid Fever per 100,000 Gallons of Milk Sold. A. 35-995 41 II3-9 B. 102,867 54 52-S C. 62,903 23 36.6 D. 5i>ii5 18 35-2 E. 71-350 25 3S-0 F. 71,690 17 23-7 G. 31-984 7 22.2 H. 77,098 17 22.0 I. 134,911 29 21-5 J- 27,247 5 18.4 K. 142,986 26 18.2 L. 43,800 8 18.2 • M. 119,889 20 16.6 N. 29,247 4 137 0. 39,286 5 12.7 P. 44,496 Pasteurized 3 6.7 Q- 31.542' 2 6.3 Then there is the general experience of Germany and other countries where the habit of boiling the milk before using is widespread. In such countries the typhoid rates have been proverbially low. In America sanitarians have been inclined to regard death-rates of 15 to 20 per 100,000 as satisfactory for cities having good water-supplies, — but these rates are twice as high as in the milk-boiling countries. Next in importance to water are the improvements needed :n the milk-supplies, — cleaner farms, better ^ Pasteurization not reported. 2/2 TYPHOID FEVER. methods of distribution, and general pasteurization for all large cities. Progress in this direction thus far has been small, but it is coming, nevertheless, and coming speedily. The additional value of good milk is being recognized by its advance in price. Certified milk commands a premium, and even the price of ordinary milk is increasing. How far these additional charges are justified by increased cost cannot be said, but the additional charges are an indication that the public is demanding a better and a safer quality of milk than it has been getting. Those interested in the subject of milk should con- sult the very elaborate report issued by the Marine Hospital Service on " Milk and its Relation to the Public Health." ^ This is an exhaustive treatise, by various authors, on all phases of the milk problem. It contains various data for several hundred epidemics of typhoid fever caused by infected milk. ' Hygienic Laboratory Bulletin, No. 41. CHAPTER XII. THE FINANCIAL ASPECT. However much we may dislike to measure human life in gold dollars, or to balance human suffering against the coin of the realm, we cannot but admit that the financial aspect of typhoid fever is an important matter in the United States, and that it has a ver\' practical bearing on the whole problem. Hence, we are com- pelled to devote some attention to the argumentum ad crumenam. Having discussed this subject at some length in his book on " The Value of Pure Water," the author takes the liberty of presenting here in an abridged form some of the conclusions there reached. Financial Value of Human Life. The financial value of a human life is generally taken for purposes of calcu- lation as $5,000, but according to Marshall O. Leighton it varies at different ages from $1,000 to 87,000, as shown by the table on page 274. It so happens that persons are most exposed to typhoid fever near the age when their life-value is considered greatest. By combining the life-value at different ages with the age distribution of persons dying of typhoid fever, the resulting average value of persons dying from 273 274 TYPHOID FEVER. typhoid fever is found to be to the figure ordinarily used. t,634, which is very close Age. Estimated Value of Human Life. Per cent of Deaths from Typhoid Fever. Product of Columns 2 and 3. o- 5 years 5-10 10-15 15-20 20-25 25-30 30-35 35-40 40-45 45-50 50-55 55-60 60-65 65-70 70- Total $1,500 2,300 2,500 3,000 5,000 7>5oo 7,000 6,000 5.500 5,000 4,500 4,500 2,000 1,000 1,000 5-0 5-9 7.2 131 16. 7 13.2 9.9 $7,510 i3>57o 18,000 39,300 83,500 99,100 69,300 48,000 30,900 20,000 15,000 11,700 4,200 1,500 1,900 $463,480 Average value of life of persons dying from typhoid fever, $4,634. The percentage fatality of typhoid fever patients is sometimes stated as lo per cent, that is, ten cases for every death; but it has been shown elsewhere that 12 to 15 cases for each death would be nearer the truth. The expense of medical treatment, nursing, and medicine, the loss of wages for a month or more, together with other attending expenses and inconveniences, would doubtless aggregate at least $100 per case, or $1,000 for the ID cases corresponding to one death. If the estimate of $100 is considered too large, it may be answered that any excess is more than offset by the fact that there are THE FINANCIAL ASPECT. 275 more often from 12 to 15 cases for each death than there are 10. It may be fairly assumed, therefore, that $6,000 is a very moderate estimate of the financial loss to a community from typhoid fever for each death from that disease. What Typhoid Fever Costs the Country. The United States Census of 1900 stated that during that year there were 35,379 reported deaths from typhoid fever in the United States. If it be assumed that each one of these represents a loss of capital to the community of $6,000, the total amount is found to be $212,000,000. Of the 35,379 deaths from this disease, probably three-quarters of them at least could have been prevented ; that is, the needless loss of vital capital was about $150,000,000. This was for only one year, and the same thing is con- tinually going on, although, thanks to sanitary science, to a lessening extent. Such figures as these are often set forth with some variations to show the effect of typhoid fever. They have but little definite value, but, taken in connection with the effects and cost of water filtration and other sanitary measures, they serve to show the enormous saving that it is possible to bring about. To filter all the water-supplies of the important cities of the country, and to institute such sanitary reforms that three-quarters of the deaths from typhoid fever would be prevented, would cost only a small part of the loss from this disease. As an illustration of what can be done, let us consider the effects of water filtration. 2/6 TYPHOID FEVER. EFFECT OF FILTRATION ON DEATH-RATES AT ALBANY, N.Y., AND A COMPARISON WITH TROY, N.Y., WHERE THE WATER WAS NOT FILTERED, ALBANY. Death-Rates per 100,000. 1894-98, Before Fil- tration at Albany. 1900—04, After Fil- tration at Albany. Difference. Per Cent Reduction of Death- Rates. Typhoid fever Diarrheal diseases .... Children under 5 years . . Total deaths. . . . 104 125 606 2,264 26 53 309 1,868 78 72 297 378 75 57 49 17 TROY. Typhoid fever Diarrheal diseases . . . Children under 5 years . Total deaths . . 57 57 116 102 14 531 435 96 2,157 2,028 129 Filtered water was introduced into Albany in li supply of Troy has remained practically unchanged. The water- Effect of Filtration. Typhoid fever is by no means the only disease transmitted by contaminated water. Dysentery and various other diarrheal diseases precede it or follow in its train, and in most instances these are probably due to the same general sources of contami- THE FINANCIAL ASPECT. 277 nation as those which caused the typhoid fever, although, of course, to different specific infections. The reduction of the typhoid fever death-rate following the substitu- tion of a pure water for a contaminated water is often accompanied by a drop in the death-rate from other diseases. Thus, if the five years before and after filtered water was introduced into Albany, N.Y., are compared, it will be seen that the reductions in deaths from general diarrheal diseases and the deaths of children under five years of age were much greater than in the case of typhoid fever. There was also a reduction in malaria, but this probably represents faulty diagnosis of typhoid fever cases before the introduction of the filters, rather than a real reduction of malaria. That the reduction of infant mortality and deaths from diarrheal diseases was not due to other conditions seems probable from the fact that in the neighboring city of Troy, where the water-supply was not changed, there was no such diminution during the same period. Hazen, in his paper on "Purification of Water in America, " read at the International Engineering Congress at St. Louis, called attention to this same fact, that after the change from an impure to a pure supply of water, the general death-rate of certain communities investi- gated fell by an amount considerably greater than that resulting from typhoid fever alone — indicating either that certain other infectious diseases were reduced more than typhoid fever, or that the general health tone of the community had been improved. Thus, for five cities where the water-supply had been radically improved he found : 2/8 TYPHOID FEVER. Per 100,000 Reduction in total death-rate in five cities with the introduction of a pure water-supply 440 Normal reduction due to general improved sanitary conditions, computed from average of cities similarly situated, but with no radical change in water-supply 137 Difference, being decrease in death-rate attributable to change in water-supply . 303 Of this, the reduction in deaths from typhoid fever was 71 Leaving deaths from other causes attributable to change in water- supply 232 From these facts it is evident that to place the finan- cial loss to a community as $6,000 for each death from typhoid fever due to the public water-supply is to use too low a figure. It probably ought to be several times as high; but recognizing the lower financial value placed on the lives of infants, and the less serious character of the other diseases, and wishing to be as conservative as possible, for the reason that typhoid fever is not entirely a water-borne disease, $10,000 per typhoid death has been used in the calculation which follows. Since typhoid fever is a disease which may be trans- mitted in other way than by water it is necessary to allow a certain death-rate for these other causes, for even in a city where the water-supply is perfect there may still be some typhoid fever. To establish a figure, this typhoid fever of miscellaneous origin is a difficult matter, but for purposes of calculation we may assume it to be determined and represent it by the letter N. It is used as a synonym for the "residual" typhoid already referred to, and is, of course, variable and subject to local conditions. THE FINANCIAL ASPECT. 279 If we assume that all typhoid fever in excess of TV is due to the water-supply, and if we assume that the daily consumption of water is 100 gallons per capita, then letting T equal the typhoid fever death-rate per 100,000 — {T — N) 10,000 = loss to the community in dollars for 365 X 100 X 100,000 gallons of water, or D = (T - N) 1,000 = 2.75 {T — N), where D stands for 365 the loss in dollars per million gallons of water used. Suppose the average typhoid fever death-rate for a community which has a somewhat polluted water-supply has averaged 43 per 100,000 for a period of five years, and suppose that for this place the value of N is estimated as 15, then — D = 2.75 (43 — 15) = $76.72 if the per capita con- sumption is 100 gallons. If the consumption per capita is 115 gallons, D would be \^^ of $76.72, or $66.71; if it were 63 gallons per capita, then D would equal -^3^- of $76.72, or $121.77. The following examples illustrate to what extent the sanitary value of a polluted public water-supply is in- creased by an efficient system of filtration: Lawrence, Mass. — Water-supply, Merrimac River, filtered by a slow sand filter. Population, 70,000. Water consumption, 40 gallons per capita daily. Before filtration the typhoid fever death-rate was 121 per 100,000; since then it has been 26. Before filtration I? = 2. 75 (121 — 20) X ^^%° = $693. After filtration D =. 2.75 (26 — 20) X ^^jV" = $4i- Increase in sanitary value = $693 — $41 = $652 per million gal- lons, or $665,000 per year, or $9.50 per year per capita. 28o TYPHOID FEVER. Albany, N.Y. — Water-supply, Hudson River, filtered by sand filter. Population, 95,000. Water consumption, 165 gallons per capita daily. Before filtration the typhoid fever death-rate was 104 per 100,000; since then it has been 26. Before filtration D = 2.75 (104 - 20) X iff = $140. After filtration Z) = 2.75 (26 - 20) X iU = ^10. Increase in sanitary value = $140 — $10 = $130 per million gallons, or $450,000 per year, or $4.75 per capita per year. Binghamton, N.Y. — Water-supply, Susquehanna River, filtered by a mechanical filter. Population, 42,000 (approximately). Water consumption, 160 gallons per capita daily. Typhoid fever death-rate before filtration, 49; after filtration, ii per 100,000. Before filtration Z? = 2 . 75 (49 - 11) X M£- = $65. After filtration D = 2.75 (11 - 11) X {U = o. ' Increase in sanitary value = $65.00 per million gallons, or $160,000 per year, or $3 . 80 per capita per year. Watertown, N.Y. — Water-supply, Black River filtered by Mechanical filter. Population, 25,500 (approximately). Water consumption, 160 gallons per capita daily. Typhoid fever death-rate before filtration, 68 per 100,000 ; after filtration, 19.5. Before filtration Z? = 2.75 (68 - 20) X ^U = $82.50. After filtration Z) = 2 . 75 (20 - 20) X -\%°- = o. Increase in sanitary value $82.50 per million gallons, or $120,000 per year, or $4.75 per capita per year. Illustrations like the above might be multiplied, but the four cases selected are sufficient to illustrate the general fact. It is easily seen from them that the filtra- tion of a polluted public water-supply increases to a very great extent the vital assets of a community, and the increase in most cases is many times greater than the cost THE FINANCIAL ASPECT. 28 1 of constructing and operating the works. Money paid to the doctor, the apothecary, and the undertaker is not, in one sense, a loss to a community, as it is merely a trans- ference of money from one man's pocket to another's, but in the broader sense any loss of productive capacity or any unnecessary expenditure is a loss. Deaths from typhoid fever and from other diseases, however, represent a very material loss of the productive capacity of a community, and consequently a decrease in what may be termed the "vital assets." In the case of the city of Albany, for instance, the increased worth of the water to the city, because of its efficient filtration, amounts to $475,000 per year, of which at least $350,000 may be considered as a real increase in the vital assets of the city. If in the formula D = $2.75 {T - N) we let T - AT = I, then D = $2.75; that is, a decrease in the typhoid fever death-rate of i per 100,000 causes an increase in the vital assets of the city of $2.75 for each million gal- lons of the public water-supply (assuming this to be 100 gallons per capita), or $0.10 per capita per year for each unit reduction of the typhoid fever death-rate per 100,- 000. In other words the decrease in the typhoid death- rate per 100,000 divided by 10 gives the increased vital assets of the community in dollars per capita per year. Thus in the case of Albany, above given, the reduction in the typhoid fever death-rate was 78 per 100,000. On the basis of 10 cents per capita per unit decrease, this would amount to $0.10 X 78 X 95,000 = $741,000 per year, assuming a per capita consumption of 100 gallons daily, or $450,000 for a per capita consumption of 165 gallons daily, which is the figure stated above. 282 TYPHOID FEVER. Looking at the matter in another way, it may be said that the purification of a polluted water is a sort of life insurance for the people, the value of which is equal to ID cents per capita for each unit decrease in the typhoid fever death-rate per 100,000 which it brings about. Such a sum capitalized represents a large amount of money. In Albany, for example, where the typhoid fever death-rate has been reduced 78 per 100,000, the annual saving of life-value would be $7.80 per capita. Capitalized on the basis of an annual life-insurance premium of $17 per thousand, this would represent an insurance policy of about $460 per year for each inhabi- tant, or $2,300 for each head of a family. Effect of Contamination. The average death-rate from typhoid fever in American cities which have more than 30,000 inhabitants is about 35 per 100,000. Apply- ing formula (i), and assuming a value of 20 for N, then D = 2.75 (35 - 20) - $41-25; that is, the average depreciation value of the water-sup- plies of our American cities, taken as a whole, is $41.25 per million gallons, because of their unsanitary quality, or about $15,000 per annum for each million gallons a day of supply. The above figure takes into account both good and bad supplies. The average typhoid fever death-rate in those cities which have reasonably good water-supplies may be taken in round numbers as about 20, while in those cities which have supplies more or less contaminated it varies from this up to 40 or 60. In some of the worst cases it is more than 100 per 100,000. In Pittsburg, for example, the typhoid death-rate for several years has averaged 120. THE FINANCIAL ASPECT. 283 Here, according to formula (i), D = 2.75 (120 — 20) = $2 7 5 per million gallons. This is figured, however, on a per capita water consumption of 100 gallons a day. The actual consumption is about 250 gallons per capita per day; hence D should be taken as o-| ^ of S275, or Siio per millioji gallons. Each million gallons of polluted Allegheny River water pumped to Pittsburg has, there- fore, reduced the vital assets of the community by Si 10. This, for a population of 350,000, amounts to 83,850.000 per year' — a sum enormously greater than the cost of making the water pure. Classifying water supplies according to their source, the following will give a general idea as to the amount of depreciation of various types of water from the sanitary standpoint, based on general average typhoid fever death-rates : CH.\RACTER OF WATER SUPPLY. Ground waters, except in cases where pollution is excessive, or where wells are driven in rock or soil abounding in fissures Filtered waters (assuming modem methods of construction and operation) Surface waters — (a) Ordinar}' upland waters, with insignificant contamination (b) Slightly contaminated waters, with good stor- age in lakes or large reser\'oirs (c) River waters, slightly contaminated, little or no storage (d) River water=, much contaminated, little or no storage Amount of Deprecia- tion in Dollars per Million Gallons. $0.00 50.00 $0.00 to 10.00 to 25 . GO to 100. 00 50. 00 to 200. 00 284 TYPHOID FEVER. Conclusion. When the appalHng ravages of typhoid fever and the accompanying great financial losses are considered, the sums spent in preventing the disease appear beggarly. This is true all along the line from the government of the nation to that of the smallest village. We have no national department of health. We ought to have such a department, thoroughly organized and endowed with interstate authority. And the annual preventable losses from typhoid fever alone would more than support such a department. Our army medical corps is entirely inadequate to the service, and organized upon a wrong principle. The losses from typhoid fever in the Spanish War would have paid for an adequate service ten times over. Some of our states have no health departments worthy of the name, and in some there is not even an attempt made to collect the vital statistics. Even in New York state, the wealthiest state in the union, the appropria- tions for the department of health are ridiculously meager, and the work of the department is correspond- ingly insufficient for the needs of the community. Some states, on the other hand, have too many sani- tary authorities, and water-supply commissions and sewerage commissions eat up appropriations and bring about unhappy conditions of divided authority. The states provided with a strong central board of health, well organized and supported are the states in which sanitary reforms have made greatest progress. Many cities of the country have no boards of health or health officers, or, if they have, these officers are such THE FINANCIAL ASPECT. 285 only in name, serving without pay, and knowing little about the principles of sanitary science. To remedy all these conditions will cost money, but it will pay. It will pay not only in the satisfaction of having clean and healthful cities to live in, not only in the joy of having relieved the suffering and saved the dying, but it will pay in hard cash. Although this country has a long road to travel before reaching the goal of perfect sanitation, yet during the last decade it has traveled a long way on that road. The nation should be proud of the state of Massachusetts for her pioneer work in sanitary science; it should be proud of such an example as the city of Montclair, N.J., jealously guarding the health of her citizens; it should be proud of the work done by many civic organ- izations, many an editor in his chair, many a lawyer struggling for better sanitary laws, many a family physician doing self-sacrificing work that humanity never dreams of, and many an engineer working out on a large scale what the laboratory student has learned from his test tubes and his microscope. And the United States should be proud of her citizens who, in ever increasing numbers and in many states, are taking an intelligent interest in the care of their own premises, in the sani- tation of their city, and in the universally important subjects of health and cleanliness. APPENDIX I. THE USE OF DISINFECTANTS. Definitions. There are three common terms that are sometimes used interchangeably, but to do so is incorrect and tends to a confusion of ideas. These terms are disinfectants, a;itiseptics and deodorizers. Deodorizers are substances that destroy or cover up odors, without necessarily killing germs or preventing their growth. Afitiseptic substances prevent the devel- opment of bacteria, without necessarily killing them and their spores. Disinfectants actually kill the germs. Disinfectants and antiseptics differ in degree rather than in kind. Formaldehyde used in minute quantities may act as an antiseptic agent; used in larger quantities it may act as a disinfectant. Disinfectants and antiseptics may tend to reduce odors by arresting or preventing decomposition, but this is not their principal function. Deodorizers have their legitimate uses, but they are of little use in typhoid fever. When there is danger from disease germs, disinfectants only are adequate to the task. The chief objection to the use of deodorizers as a class is that they tend to give a false sense of security. Methods of Disinfection. The methods of disinfection may be divided into four groups: 287 288 TYPHOID FEVER. 1. Burning with fire. 2. Killing with dry heat. 3. Killing with hot water and steam. 4. Poisoning with chemicals. These will be discussed only in so far as they relate to typhoid fever. As the typhoid bacillus does not form spores its destruction is less difhcult than it otherwise would be, and as the germ is not thrown off into the air to any great extent the problem is simpler than in the case of diphtheria, scarlet fever, smallpox and such diseases. Fire. It goes almost without saying that the burning of infected articles destroys all germ hfe, and this is the safest and best way of destroying many things used around a typhoid patient, if they have little value. Old bedding, old handkerchiefs and cloths used as substitutes for handkerchiefs should be burned in the stove. Toilet paper may be conveniently disposed of in the same way. Sometimes the stools themselves are mixed with sawdust and burned. Dry Heat. Articles exposed to dry heat (temperatures of 150° C. or more) in an oven or "hot-air sterilizer" for an hour will have any typhoid germs that they may contain completely destroyed, so far as they lie upon the surface of the articles. Dry heat does not penetrate to the interior of packages or articles piled together as moist heat does. It is only to be used for articles that might be destroyed by moist heat. Steam. Steam under a slight pressure is useful in hospital work, but is almost never available elsewhere. A few minutes' exposure to steam which has a pressure of 15 pounds or more per square inch is sufficient to kill APPENDIX I. 289 typhoid bacilli. Steam at atmospheric pressure, that is, the steam arising from boiling water in an open dish, has practically the same effect as boiling water. Boiling. Typhoid bacilli are killed in boiling water or in streaming steam in a very few minutes, but if the water is not up to the boiling point a somewhat longer time is required. If a steam sterilizer, such as an "Arnold," is used, an exposure of 30 minutes is suf- ficient to insure safety, but if articles are put into boiling water it is better to let them remain there an hour or even two hours. Boiling is a convenient way to sterilize the knives, forks, spoons and plates used by the patient, and also bed linen, underwear, handkerchiefs, etc., although in the case of these fabrics chemical disinfectants should first be used. Chemical Disinfectants. The most useful chemical disinfectants in typhoid fever cases are : 1. Ordinary quicklime, or lime freshly slaked. 2. Chloride of lime. (Bleaching powder.) 3. Carbolic acid. 4. Corrosive sublimate, or bichloride of mercury. These chemicals are all poisons and are listed in the order of their poisonous effect. The last-named chemical is exceedingly poisonous and has to be used very care- fully, and all the more so because it has no odor to serve as a warning as in the case of carbolic acid and chloride of lime. It should be remembered also that corrosive sub- limate acts on some metals. Solutions of it should not 290 TYPHOID FEVER. be kept in metal vessels, but in wooden pails, or tubs or earthern or glass jars. It should not be used for disinfecting silverware, and one should be careful not to wash the hands in it without first removing finger rings. Solutions of chloride of lime, carbolic acid and corrosive sublimate may injure the lead pipes of plumbing fixtures if used in large quantities without flushing. In case these solutions are put into a water-closet, let the water run freely. The relative value of these disinfecting substances varies with the uses to which they are put. Generally speaking, carbolic acid and corrosive sublimate are best to use around the body of the patient and in the sick room; while chloride of lime and quicklime are most serviceable for disinfecting water-closets, fecal matter in chamber vessels, and cesspools, and for general out- of-doors work. Lime is especially valuable in country practice, while the other disinfectants are more con- venient for use in city apartments, hospitals, etc. Use of Lime. Lime is comparatively cheap, costing from less than half a cent to a cent a pound, according to locality and quantity purchased. Old Hme, which has become "air-slaked" is of no use whatever. Lime freshly burnt is known as "quicklime." It comes in irregular lumps which are easily broken. The dry sub- stances may be used for disinfecting fecal matter. In chamber vessels use about as much as the volume of the substance to be disinfected. In water-closets sprinkle freely about the seat and floor in front of the seat, and after each evacuation cover the feces with the powdered lime until white. In cesspools use about 3 to 5 pounds APPENDIX I. 291 for each cubic foot of contents. This might amount to a barrel of lime for the ordinary sized cesspool of a one- family house. Often it is more convenient to use ''milk of lime." This may be easily made by slacking the lime, that is, by mixing it carefully with something less than its own weight of water, and then adding to the hydrated lime thus made about eight or ten times its weight of water. The product is a sort of white-wash, which can be used for all of the disinfecting purposes above mentioned. It ought to be freshly prepared, but will keep a few days in a closed jar with the air excluded. Use of Chloride of Lime. Chloride of lime is also comparatively inexpensive. It can be purchased in retail lots for 3 or 4 cents a pound, and in quantities for much less. It is sold as a dry powder in sealed packages. Chemically, chloride of lime is a hypochlorite of calcium. It owes its disinfecting qualities to the "available chlorine." Some grades contain more of this than others, and are therefore worth more. Common grades contain 20 to 30 per cent of available chlorine, but some grades prepared by recently introduced electrolytic processes contain as high as 35 or 40 per cent of available chlorine. Chloride of lime may be used dry in place of ordinary quicklime, and less may be used, but quicMime is cheaper, less odorous, and on the whole better, provided enough of it is used. To prepare a disinfecting solution of chloride of lime, dissolve a third of a pound (something less than a cupful) of the dry substance in a gallon of water. 292 TYPHOID FEVER. Use about one quart of such a solution to disinfect each fecal discharge; and for disinfecting urine, add volume for volume. Allow these to stand for at least two hours in order to give time for thorough disinfection. Break up any lumps of fecal matter with a stick, and immediately burn the stick; or if a glass rod is used, sterilize the rod. Prepare the solution of chloride of lime each time when required, or at least once each day. Use of Carbolic Acid. The best grade of carbolic acid is purchased as a soHd, but it may be made liquid by adding a small quantity of water and letting the bottle stand in boiling water. Crude carbolic acid is sold as a liquid. The purer forms are not needed for disinfecting purposes. A satisfactory quality of carbolic acid can be purchased for 25 to 75 cents per gallon. A 5 per cent solution of carbolic acid is that generally used, that is, about tw^enty times as much water as acid, — or say half a cupful of carbolic acid to a gallon of water. Such a solution may be used for soaking bed linen, underwear, handkerchiefs, towels, napkins, etc., before boiling. Such fabrics should soak in the dis- infecting solution for upwards of an hour. Such a solution may be also used instead of chloride of lime for disinfecting fecal discharges and urine. For disinfecting the hands or for bathing the patient, a 5 per cent solution of carbolic acid is too strong. A 2 per cent solution, or one something less than half as strong, is preferable, and, as the acid is rather harsh to the skin, an equal volume of glycerine should be added to each quart of solution. APPENDIX I. 293 It is not so important to have these solutions freshly prepared as in the case of chloride of lime. Use of Corrosive Sublimate. Corrosive sublimate is purchased as a white crystalline solid. It costs at retail from 75 cents to a dollar per pound. It should not be used without dissolving in water. Solutions of different strengths are used for different purposes, as foUows : Strong Solution. (1:500.) Used for disinfecting fecal matter, urine, etc. Corrosive sublimate, one ounce (about a tablespoonful). Hydrochloric acid (muriatic acid), one-half ounce (about tvv'o tablespoonfuls). Water, one gallon. Permanganate of potash (10 grains) may be added to give a color to the solution, in order that it may not be mistaken for water. Common washing blueing is equally useful for this purpose. Medium Solution. (1:1000.) Used for disinfecting clothing, bed linen, etc., and often used for- fecal matter. Also used for disinfecting the hands, for disinfecting clinical thermometers, syringes, glassware, woodwork, door-knobs, etc. It is prepared by adding one teaspoon- ful of the chemical to one gallon of water. In this solution no hydrochloric acid need be added, but some- times a quantity of ammonium chloride, equal in weight to the corrosive sublimate, is used. Weak Solutions. Weaker solutions are used for dis- infecting the body of the patient, as follows : (i : 3000. ) For bathing the patient after each stool, for washing the scalp, and for general bathing. 294 TYPHOID FEVER. (i:8ooo.) May be used as a nasal spray, but for cleansing the mouth, Hps and nose, solutions of boracic acid are to be preferred. In using corrosive sublimate it should be remembered that the solutions are poisonous. Especial care should be taken with strong solutions if one has cuts on the hands. Corrosive sublimate is somewhat slower in action than chloride of lime. At least two hours' contact should be allowed. Use of Other Chemicals. Certain other chemicals may be used for disinfecting purposes in place of those mentioned, but they are not as satisfactory for typhoid fever. Among these may be mentioned : Formaldehyde solutions, i : 20. Copper sulphate (Blue vitriol), 10 per cent solution. Iron sulphate (Copperas). Zinc chloride, 10 per cent solution. Besides these there are many other substances, such as lysol, that are useful in the sick room and about the patient. Use of Urotropin. Urotropin is a valuable urinary disinfectant. It should be used only on prescription by a physician. The usual dose is 5 to 7 grains three times a day, preferably after meals, continued for two or three days, or until an examination of the urine shows that typhoid bacilli are absent. The tablets should be dissolved in a tumblerful of water (temperature less than 80° F.). Fumigation. Fumigation, as practised in the case of scarlet fever, measles, etc., is not generally considered necessary in typhoid fever. Nevertheless on account APPENDIX I. 295 of its contagiousness, fumigation is a wise precaution, especially in those instances where pulmonary complica- tions supervene. In any case, however, woodwork, door- knobs, etc., should be washed with disinfectants and the bedding, mattresses, etc., thoroughly cleansed. APPENDIX II. HOUSE FLIES. {Chiefly from a paper by Dr. L. O. Howard, Chief of the Bureau of Entomology, United States Department of Agriculture, Circular No. 71.) Common Species. There are several species of flies which are commonly found in houses, although but one of these should properly be called the house fly. This is the Musca domestica (Fig. 49 a) and is a medium-sized, grayish fly, with its mouth parts spread out at the tip for sucking up liquid substances. It breeds in manure and dooryard filth and is found in nearly all parts of the world. On account of the conformation of its mouth parts, the house fly cannot bite, yet no impression is stronger in the minds of most people than that this insect does occasionally bite. This impression is due to the frequent occurrence in houses of another fly {Stomoxys calcitrans), which is called the stable fly, and which, while closely resembling the house fly, differs from' it in the important particular that its mouth parts are formed for piercing the skin. It is perhaps second in point of abundance to the house fly in most portions of the Northeastern States. A third species, commonly called the cluster fly (Pol- lenia rudis), is a very frequent visitant of houses, par- 296 APPENDIX II. 297 ticularly in the spring and fall. This fly is somewhat larger than the house fly, with a dark-colored, smooth abdomen and a sprinkling of yellowish hairs. It is not so active as the house fly, and particularly, in the fall, is very sluggish. A fourth species is another stable fly, known as Mus- cina stabulans, a form which almost exactly resembles Fig. 49. Some Common Species of Flies and their Larvae and Puparia. (After L. O. Howard.) a. Musca dome stica, the common house fly. b. Stomoxys calcitrans, the stable &y. c. Phormia terr(Enov(E, the small blue bottle fly. d. Drosophila ampelophia; the small fruit fly. e, /, g. Puparia. h, i, j. Larvct. the house fly in general appearance, and which does not bite as does the biting stable fly. It breeds in decaying vegetable matter and in excrement. Several species of metallic, greenish or bluish flies are also occasionally found in houses, the most abundant of which is the so-called blue-bottle fly {Calliphora ery- 298 TYPHOID FEVER. throcephala). This insect is also called the blow-fly or meat-fly and breeds in decaying animal material. A smaller species, which may be called the small blue- bottle fly, is Phormia terroenovce; and a third, which is green in color and about the size of the large blue-bottle, is Lucilia ccesar. There is still another species, smaller than any of those so far mentioned, which is known to entomologists as Homalomyia canicularis, sometimes called the small house fly. H. canicularis is distinguished from the ordinary house fly by its paler and more pointed body and conical shape. The male, which is much commoner than the female, has large pale patches at the base of the abdomen, which are translucent when the fly is seen on a^ window pane. Still another fly, and this one is still smaller, is a jet- black species known as the window fly (Scenopinus jenestralis). It breeds in the dust under carpets, and its larva is a white, very slender, almost thread-like creature. In the autumn, when fruit appears on the sideboard, many specimens of a small fruit fly {Drosophila ampelo- phila) make their appearance, attracted by the odor of overripe fruit. A small, slender fly, not infrequently seen in houses, especially upon window panes, is Sepsis violacea. All of these species, however, are greatly dwarfed in numbers by the common house fly. In 1900 collections were made of the flies in dining rooms in different parts of the country, and out of a total of 23,087 flies, 22,808 were Musca domestica, that is, 98.8 per cent of the APPENDIX II. 299 whole number captured. The remainder, consisting of 1.2 per cent of the whole, comprised various species, including those mentioned above. Life History of Flies. Musca domestica commonly lays its eggs upon horse-manure. This substance seems to be its favorite larval food. It will deposit its eggs on cow manure and will also breed in human excrement, and from this habit it becomes very dangerous to the health of human beings, carrying, as it does, the germs of intestinal diseases such as typhoid fever and cholera from excreta to food supplies. It will also lay its eggs upon other decaying vegetable and animal material, but of the flies that infest dwelling houses, both in cities and on farms, a vast proportion comes from horse manure. In hot weather each female fly lays about 120 eggs, which hatch in eight hours, the larva period lasting five days and the pupa five days, making the total time for the develop- ment of the generation ten days. The larvae molt twice, hence there are three distinct larval stages. There is thus abundance of time for the development of twelve or thirteen generations in the climate of Washington every summer. The periods of development vary with the climate and with the season, and the insect hibernates in. the puparium condition in manure or at the surface of the ground under a manure heap. It also hibernates in houses as adult, hiding in crevices. The number of eggs laid by an individual fly is so large, that the enormous numbers in which the insects occur are easily accounted for, especially when we con- sider the abundance and universal occurrence of appro- priate larval food. In order to ascertain the numbers in 300 TYPHOID FEVER. which house-fly larvae occur in horse-manure piles, a quarter of a pound of rather well-infested horse manure was taken on August 9, and in it were counted 160 larvae and 146 puparia. This would make about 1200 house flies to the pound of manure. This, however, cannot be taken as an average, since no larvae are found in perhaps the greater part of ordinary horse-manure piles. Neither does it show the limit of what can be found, since about 200 puparia were found in less than i cubic inch of manure taken from a spot 2 inches below the surface of the pile where the larvae had congregated in immense numbers. Movements of Flies. Most writers claim that flies do not travel far from the locality in which they breed, and little is known as to what distance they may cover. A single stable in which a horse is kept will supply house flies for an extended neighborhood. Packard thinks that flies can scent their food for several miles and may fly 20 or 30 miles a day if aided by winds. Undoubtedly the wind plays the greatest part in these long journeys of flies, and there seems to be good reason to believe that most flies do not travel far from the vicinity of their breeding places. Flies and Temperature. Flies, hke all insects, are most active in warm weather. On cold days, especially in the autumn, they become dormant and seek sheltered spots and warm places. In order to determine the time of greatest prevalence of flies in New York City, Mr. D. D. Jackson made some interesting observations during the summer of 1907, in connection with a report to the Merchants' Association. APPENDIX II. 301 Many cages were placed in different parts of the city, especially along the water-front, and the number of flies caught at each place was counted daily. The following figures show the relative prevalence of flies at one of the fly-cage stations in Brooklyn. Date. Week Ending — Number of Flies Caught During the Week. Date. Week Ending — Number of Flies Caught During the Week. May 4 II 18 25 June I 8 15 22 29 July 6 13 20 27 Aug. 3 10 I 3 2 8 34 75 244 921 2696 4165 5727 6224 3926 Aug. 17 24 31 Sept. 7 14 21 28 Oct. 5 12 19 26 Nov. 2 9 16 1165 435 99 584 888 592 182 52 47 51 32 22 7 Longevity of Flies. The longevity of flies is not well known. It is said that in the open flies may live a sea- son, but that when confined in jars and cages they often do not live more than a week or ten days. It is said also that flies which have been infected with certain disease germs, as for instance, the bacilK of anthrax and tuberculosis, succumb more quickly than others not infected kept under the same conditions. Means of Prevention. The problem of preventing the house fly from breeding has not yet been solved. Experi- 302 TYPHOID FEVER. ments have been made to destroy the maggots in horse manure by the use of kerosene, crude oil and chloride of lime, but the results have been only moderately success- ful. And at the present time the best method of avoiding the fly nuisance appears to be to build for the reception of stable manure large and tightly closed pits, well venti- lated and screened, and so constructed that little direct light may enter. Box privies are a nuisance from many points of view and are dangerous as breeding places of flies. If used at all they should be conducted on the earth-closet prin- ciple, and a free use of earth and powdered lime should be made. Howard says that "people living in agricultural com- munities will probably never be rid of the pest, but in cities, with better methods of disposal of garbage and with lessening of the number of horses and stables consequent upon electric street railways and auto- mobiles, the time may come before long when window screens may be discarded. Absolute cleanliness will always result in a diminution of the numbers of the house fly. Horse manure should be gathered and removed promptly, both from streets and from stables; garbage should be collected frequently; and aU forms of excrement, dead animals and decaying organic matter of every description promptly taken care of." APPENDIX ni. THE ESTIMATION OF POPULATION. In most countries a general census is made once in ten years. In the United States this is done in those years which are divisible by ten, that is, in 1880, 1890, 1900, etc., but in England and in Canada the general census is taken in the year following that, that is, in 1891, 1901, etc. In many of the states an intermediate census is taken between the federal censuses, that is, in 1895, 1905, etc. In some cities censuses are taken each year, but this is not common, although an aimual record is often kept of the number of school children, the number of voters, the number of houses, etc., which are useful in making approximate estimates of the population. The records of the United States census are published by the Census Bureau of the Department of Commerce and Labor, and various bulletins containing them can be obtained by addressing the Director of the Census Bureau, Washington, D.C. In the censal years the exact figures given by the census should be used in calculating death-rates, but in the years between censuses it is necessary to estimate the population. There are various ways of doing this, but the one most commonly used is based on the assumption that during the period between the two censuses the population increases gradually, so that the estimate 303 304 TYPHOID FEVER. merely involves the application of the rule of three. Thus, if the population of a certain town was 10,000 in 30,000 30,000 10,000 ^ ^ ' ^^f^ ^ w s >ip y CM h- g .^ <^ ^- \^'^ O) 5 II t- .^ -J^ y- 1- < ^ ^ ;^^^ to t- CO < 1880 1885 YEAR Fig. 50. Diagram Showing the Arithmetical and Geometrical Methods of Estimating Population. 1880, and 20,000 in 1890, the estimated population in 1887 would be 17,000. It is somewhat more difficult to correctly estimate populations in the years following a census, for, in this case, there is but one fixed population to reckon from. APPENDIX III. 305 There are-two methods commonly used for estimating this extra-censal population, — the arithmetical and the geometrical. The arithmetical method, which is the one used by the United States Census Bureau, assumes that the annual increase in population after the censal year is the same as the average annual increase in population during the period between the last two censuses. Thus, in the town above mentioned, where the population in 1880 was 10,000 and in 1890, 20,000, the estimated population for the year 1892 would be 22,000. The geometrical method is based on percentage increase and assumes that the annual percentage increase in popu- lation in the years after the census is the same as the average annual increase in the period between the last two censuses. Thus, in the town referred to, the popu- lation increased 100 per cent between 1880 and 1890, which would be 7.18 per cent per year. If this rate were continued after 1890, then the population in 1891 would be 21,000 and in 1892, 23,000. The formula for computing population in this way is: P^ = P^ (1 -r r) n in which P^ is the population desired, P^ the population given by the last census, n the number of years since the last census, and r the rate of increase. This is the same formula as that for compound interest. In any estimate of this sort it is necessary to take into account local conditions, as these may be such as to make the application of either formula untrustworthy. Often the data showing the increase in the number of school children, the number of houses, etc., may be used as a guide in estimating populations outside of the census returns. It is particularly necessary not to place undue 306 TYPHOID FEVER. confidence upon formulae in the case of rapidly growing towns or in communities where, through the introduction of manufacturing or some other great cause, there have been unusual changes in the population. The United States Census Bureau now prepares annual estimates of population for all the large cities of the United States, that is, for those which have a population of 30,000 or more, and by reason of their official character these estimates are more and more com- ing to be used for the purpose of calculating death-rates. In studying the records of death-rates in published reports, one should be careful to find out what basis of population was used in calculating them. For instance, — a death-rate for the year 1899 might be based upon a^ population estimate nine years after a census. The census of the following year might show that this estimated population was far from the truth, and that some other population should have been used. In studying old records, therefore, it is wisest to recalculate the rates, using the number of deaths as given and the new estimates of population made in the fight of later census returns. To this end the published typhoid statistics of a city should include the actual number of deaths as well as the death-rates, or if the latter only are given, the population used in computing them should be stated clearly. It is customary to use but a single figure for the popu- lation for any one year, and not to make any difference between months. The estimated population in the middle of a year is taken as the population for the entire year. APPENDIX IV. CORRECTED DEATH-RATES. {From the Annual Report of the Massachusetts State Board of Health, 1902.) The State of Massachusetts has become so densely settled, so far as relates to its urban population, as to require a better method of computing the death-rates of large cities than that which is usually employed, when it is desirable to compare the death-rates of such cities with each other. The following tables are presented for the purpose of showing the method of comparing the death-rates of different cities with each other, when the conditions as to the relative numbers of persons of different sexes and ages are not the same in each. The crude or recorded death-rate of any city for a given year, as obtained by comparing the existing population with the number of deaths in the year, may be compared with the death-rate of the same city for any other year or series of years, but it cannot be compared with that of another city, for the same year, unless the populations of the two cities have an identical relative distribu- tion of the population by sexes and ages. For example: the crude death-rates of the older cities and towns of the Atlantic sea-coast cannot properly be compared with those of new western cities, in which the relative number of persons of young and healthy ages is in excess of that in the former cities, while the population at advanced ages is also correspond- ingly smaller. For this reason the registrar-general of England has devised the method of referring the figures of different com- munities, cities and towns to some standard population, such as that of the country at large, or, as advised by other experts, to that of some very healthy population, like that of Sweden. 307 3o8 TYPHOID FEVER. In the following table the population and deaths in the State at large are assumed as a standard, and the death-rates of the cities are compared with this standard. The method is fully explained in the last edition of Newsholme's "Vital Statistics." The statistics of the year 1900 are here selected for presenta- tion because the census enumeration was taken in that year. The data for sexes and ages, however, were only published for cities having a population of 25,000 or more in each. This includes 20 of the large cities of Massachusetts. In certain cities the death-rate is unfavorably influenced by the presence of public and private institutions, in which a con- siderable number of non-resident patients are treated whose deaths should not be credited to the death-rate of those cities. An allowance has therefore been made of 419 deaths of such non- residents in Boston, of 119 in Worcester, of 79 in Taunton, and of 90 in Chelsea, all of which occurred in sixteen public and private institutions during the census year 1900. ' For the purposes of this comparison a mean annual mortality of the State by ages and sexes for the three years 1899, 1900 and 1901 was calculated and applied to the population of each city in this group. This mean annual rate for each sex and age is shown in the following table: — DEATH-RATES BY SEXES AND AGES. 1899-1901. Ages. o- S 5-10 10-15 15-20 20-25 Males. Fe- males. Per- sons. 58.41 4-74 2.84 48.00 4.60 2.88 53-21 4.67 2.86 4.70 6.71 4-43 5-94 4-56 6.30 Ages. 25-35 35-45 45-55 55-65 65 + Males. 7.96 10.48 16.26 30.96 88.60 Fe- males. 7-31 9.42 14.20 26.51 82.78 Per- sons. From this table it appears that the death-rate at each age period between 5 years and 55 years was less than that of the State for all ages (which was 17.48 for the three years). Under 5 years and over 55 the death-rate is much higher than the com- APPENDIX IV. 309 bined death-rate of the State. If, therefore, the proportion of the total population living at different ages differs much in different cities or communities, then the total death-rates at all ages will also differ, independently of sanitary conditions. The same rule applies to sex distribution. At all of the age periods, except ages 10-15, the female death-rate is lower than that of the male; hence an excess of females also tends to lower the general death-rate irrespective of sanitary conditions. CENSUS OF I poo. Age Distribution of Populat ion of Ages. Massachusetts. Holyoke. Salem. Males. Females. Males. Females. Males. Females. 0— 5 years . 505 501 610 618 530 520 5—10 years . 457 456 550 556 506 473 10-15 years . 407 411 480 498 411 427 15-20 years . 411 437 448 525 405 449 20-25 years . 461 534 454 627 449 519 25-35 years . 921 955 849 972 842 920 35-45 years . 704 708 658 643 631 710 45-55 years . 470 492 398 411 448 523 55-65 years . 292 334 216 244 286 377 65 years and over 224 286 83 140 220 328 Unknown . . 23 II 12 9 13 13 4,875 5,125 4,758 5,242 4,741 5,259 10,000 10,000 10,000 To illustrate this principle the foregoing table is presented, containing the distribution of the population by sexes and ages in the State at large, and in the two cities, Holyoke and Salem. In Holyoke the combined population at ages 0-5 and all over 55 constituted 19. i per cent of the whole population, while that of Salem at the same ages was 22.6 of the whole. In the case of 3IO TYPHOID FEVER. Holyoke the percentage of the population at these ages was less than that of the State for the same ages, notwithstanding its high birth-rate, but its population at advanced ages is relatively small, as is usually the case in comparatively new cities. In Salem, a much older city, the population under 5, and also that which is over 55, is greater than that of the State at the same ages, thus favoring a higher death-rate in Salem and a lower one in Holyoke than that of the State at large. The method of correcting the death-rates for sex and age dis- tribution is shown in the following tables: — RECORDED AND CORRECTED DEATH-RATES PER 1,000 PERSONS LIVING IN MASSACHUSETTS CITIES OF MORE THAN 25,000 INHABITANTS IN 1900. I 2 3 4 5 Cities in the Order of Their Corrected Standard Death- Factor for Correction for Sex and Recorded Death- Corrected Death- Compara- tive Death-Rates. rates. Age Dis- rates. rates. Mortality tribution. 1900. 1900. Figure. Massachusetts 17.48 I. 000 18.23 18.23 1. 000 Brockton. . . . 16.27 1.074 13-85 14.87 0.816 Maiden . . 17.02 1.027 14-53 14.92 0.818 Newton . . 17.06 1.024 15.01 15-37 0.843 Haverhill 17.67 0.989 15-55 15-38 0.844 Somerville . 17-30 I. 010 15-67 15-83 0.868 Fitchburg . 17.02 1.027 15-67 16.09 0.883 Chelsea . . 17.77 0.984 16.42 16.16 0.886 Lynn . . . 16.80 1.040 15-91 16.55 0.908 Gloucester . 1733 1.009 17.00 17-15 0.941 Cambridge . 16.54 1.056 16.54 ■ 17.47 0.958 Springfield . 17-31 I. 010 18.93 19. 12 1.049 Salem . . . 17-95 0.974 19.86 19-34 1.061 Worcester . 16.56 1.056 18.33 19.36 1 .062 Taunton . . 16.89 1-035 19-43 20.09 1. 102 Lowell . . . 16.07 1.088 19.48 21.19 1-163 Boston . . . 16.26 1-075 20.08 21.59 1. 184 New Bedford 17.07 1.024 21. 19 21.70 1. 190 Lawrence . 16.09 1.086 20.40 22. 15 I. 215 Fall River . 15.90 1.099 21-53 23.66 1.297 Holyoke . . 15-55 1. 124 21.96 24.68 1-354 APPENDIX IV. 311 In this table the Standard Death-rate signifies the death-rate at all ages calculated on the hypothesis that the death-rates at each of the ten age periods in each city were the same as in Mas- sachusetts during the three years 1899-1901, the death-rate at all ages in Massachusetts during that time having been 17.48 per 1,000. The Factor for Correction is the figure by which the crude or recorded death-rate should be multiplied in order to correct for variations of sex and age distribution. The Corrected Death-rate is the recorded death-rate multiplied by the Factor for Correction. The Comparative Mortality Figure represents the Corrected Death-rate in each city, compared with the Re- corded Death-rate at all ages in Massachusetts in 1900 taken as 1000. The figures in this column (5) may be read as follows: after making approximate corrections for differences of age and sex distribution, the same number of living persons that gave 1,000 deaths in Massachusetts in 1900 gave 816 in Brockton, 818 in Maiden, 1,354 in Holyoke, etc. The first column in the table is obtained by assuming that the mean mortality in Massachusetts in the three years 1899-1901 prevailed in each city. The age and sex distribution of each of these cities at the census of 1900 being known, the mean mortality in Massachusetts in 1899-1901 is applied to the population thus constituted, and the result is the series of death-rates in column i. The differences in the death-rates of the cities in this column are therefore caused only by the difference in the age and sex distri- bution of their inhabitants. The following example shows the method of obtaining these standard death-rates: — The population of Holyoke in 1900 was 45,712; the total num- ber of calculated deaths in Holyoke was 711; the standard death- . r 71 1 X 1000 rate was, therefore, ' = 15.55. 45,712 Now the mean annual death-rate of Massachusetts in 1899-1901 was 17.48. This should be the same as the calculated death-rate for Holyoke, which was obtained by applying the mean annual 312 TYPHOID FEVER. death-rate of Massachusetts at the different age groups to the population of Holyoke at the same ages. Mean Annual Death-Rate in Massachusetts, Population of Calculated Num- 1899-1901, per Holyoke. ber of Deaths Ages. 1000 Living at 1900. in Holyoke. Each Group of Ages. Males. Females. Males. Females. Males. Females. Under 5 years 58.41 48.00 2,787 2,824 163 135 5-10 years . 4 74 4 bo 2,514 2,542 12 12 10-15 years . 2 84 2 88 2,194 2,276 6 6 15-20 years . 4 70 4 43 2,048 2,400 10 II 20-25 years . 6 71 5 94 2,075 2,866 14 17 25-35 years . 7 96 7 31 3,881 4,445 31 32 35-45 years . 10 48 9 42 3,006 2,940 31 28 45-55 years . lb 26 14 20 1,818 1,879 30 27 55-65 years . 30 q6 26 51 9«5 1,113 30 29 65 years and over 88 60 82 78 3«i 642 34 53 . Unknown . . 55 41 21,744 23,968 361 350 45,712 711 But the calculated or standard death-rate for Holyoke is lower, as shown above, which must arise from the fact that the distribu- tion of ages and sexes in the Holyoke population is more favorable than in the State at large. The standard death-rate in Holyoke, being lower than that of the State, must be raised in a certain ratio in order to bring it into comparison with that of the State. It must be increased in the proportion of 15.55 to 17.48. The factor for correction for age and sex distribution, by which the recorded death-rate of Holyoke must be multiplied in order to make it comparable with that of Massachusetts is APPENDIX IV. 313 — — = 1. 1 24. We have employed a triennial correction figure 15-55 as a constant, lia%'ing the census year 1900 as the middle year of the three. Any error which may be due to the use of a triennial correction figure instead of a special correction figure for a single year is so small that it may practically be disregarded. By multiplpng the recorded death-rates in column 3 by the factors for correction, the corrected death-rates in column 4 are obtained. These are the death-rates which would have been recorded in each town had its population been identical, so far as age and sex distribution are concerned, with the population of Massachusetts. APPENDIX V. BACTERIOLOGICAL DESCRIPTION OF THE TYPHOID BACILLUS. Name. B. der Abdominal typhus, Eberth: Virchow's Archiv. LXXXI, 1880. B. typhosus, Zopf: Spaltpilze, 1885. Morphology. Slender rods, with rounded ends, occasionally occurring as fila- ments, actively motile. Length, i to 3 yu; diameter 0.5 to 0.8 n. , Flagella, peritrichiate, 8 to 12 in number, long and undulating. Spores never have been observed. Stains readily with watery dyes. Does not stain by Gram's method. Killed by exposure to a temperature of 65° C. for ten minutes. Aerobic and facultatively anaerobic. Nutrient Broth. SUghtly turbid; no pellicle. Gelatin Plate. Deep colonies: roimd, gray to yellowish brown, entire. Surface colonies: at first small, punctiform, becoming flat, round- ish, gray, glistening, with irregular borders; microscopically, colorless, translucent, becoming grayish yellow, darker in the center, marmorated; border undulate to lobate; strongly refract- ing. No liquefaction. Surface growth, thin, whitish, irregular. 314 APPENDIX V. 315 Gelatix Stab. Line of puncture, filiform, beaded. Xo liquefaction. 'Milk. Xo coagulation. SHght acidit}', -^hich occasionally changes after a time to alkalinit}'. Litmus Milk. Slight acid reaction; variable, no coagulation. Potato. Growth a pure white glistening streak, thin or scarcely ^-isible. Agar Slant. Growth thin translucent, smooth, sUmy, spreading, — well marked after 24 hours at 37° C. Lactose Litmus Agar. Color of growth bluish. Nitrate Broth. Xitrates reduced to nitrites. tsTDOL Production. Indol not produced, or, if so, only a small amount- Fermentation Tests. Dextrose broth. Xo gas produced; httle acid. Lactose broth. X'o gas produced; no acid. • Saccharose broth. X'o gas produced; no acid. -Maltose broth. Xo gas produced; some acid. Mannite broth. Xo gas produced; some acid. Xeuir-AL Red Glucose Broth. Xo color change. Reaction TvIth Anti -typhoid Serum. Readily agglutinated by highly diluted serum. It is best to use a powerful senim obtained from an immuxdzed animal rather than from the blood of a t}"phoid patient. 3i6 TYPHOID FEVER. Pfeiffer's Test. This consists in injecting a ten times fatal dose of the bacillus, together with a small quantity of serum from an animal highly immunized against the typhoid bacillus, into the peritoneal cavity of a guinea pig. If the suspected organism is the typhoid bacillus, then the bacilli are converted into granular masses (tested by removal and examination of a little peritoneal fluid after half and after one hour), and the animal does not die, while a control animal, injected with the bacillus alone, dies. Similarity to other Bacteria. The typhoid bacillus in many respects resembles other bacteria, most of which are of intestinal origin. One of these is bacil- lus coli communis, or B. coli, an almost constant inhabitant of the intestines of warm-blooded animals. Because of this fact it is an organism commonly used as an index of fecal pol- lution. Complete descriptions of these various allied organ- isms are given in most works on Bacteriology. APPENDIX VI. TESTS FOR THE DIAGNOSIS OF TYPHOID FEVER. The Widal Test. {From a Circular of Information issued by the Department of Health of the City of New York.) The investigations of Griiber, Widal and others, publislied in 1896, show that the blood of persons suffering from or having recently had typhoid fever, contains, as a rule, after the fifth day of the disease, substances w^hich when added to a broth culture of the typhoid bacilli arrest the characteristic movements of these organisms and cause them to become clumped together in masses. It has been further shown that occasionally the blood of per- sons suffering from other diseases possesses this peculiar property; but that when the agglutinating substances are present in these it is in relatively small amount. These substances are also occa- sionally present in small amount in other diseases and even in health. The reaction is, therefore, a quantitative rather than a qualitative one. The results of a very large number of examinations made here in New York and elsewhere show, that if the blood contains agglutinating substances in sufficient amount to cause a prompt and marked reaction, when one part of serum or blood solution is added to twenty parts of a culture of the typhoid bacillus, the presence of a previous or existing typhoid infection may, for diag- nostic purposes, be practically considered as established. In estimating the diagnostic value of a negative result from this test, we must remember that the reaction is rarely, if ever, present 317 3l8 TYPHOID FEVER. until at least five days after the appearance of symptoms; that' it is occasionally absent in cases of typhoid fever until the third or fourth week, or even, until convalescence is established; that when developed it may disappear after a few days; and that no definite relation between the severity of the disease and the degree and time of development of the substances causing the reaction has been established. For these reasons a single negative result in any suspected ca^e only renders doubtful the existence of typhoid fever. In those cases in which the reaction is absent after the ninth day, it may be reasonably assumed that the large majority will not prove to be typhoid fever, and the absence of the reaction in all of several different cases of a suspected group, or after repeated examinations in any single case, affords evidence of very decided value in excluding the diagnosis of typhoid fever. Either dried blood or the serum obtained from a blister may be sent for examination. Outfits for preparing dried blood specimens may be obtained at any of the stations of the Depart- ° ment of Health, a list of which will be forwarded on request. Serum outfits may be obtained at any of the Department's Borough offices, or will be mailed on application. Directions for Preparing Specimens of Blood. The skin cov- ering the lobe of the ear is thoroughly cleansed and then pricked with a clean needle deeply enough to cause several drops of blood to exude. Two large drops are then placed on the glass slide, one near either end, and allowed to dry in the air without being spread out on the surface of the slide. The specimens should never be heated or treated with any chemical fixative. After drying, the slide is to be replaced in the holder and returned in the addressed envelope to a culture station, or mailed to the laboratory. The blank giving the history of the case must be filled out in full and forwarded with each specimen. The data thus obtained are for record. Directions for Obtaining Specimens of Serum from Blisters. The shield (designed to protect the blister from rupture) is applied to the skin somewhere on the anterior portion of the body. The piece of canthos plaster is then fixed within its center. After APPENDIX VI. 319 10 to 12 hours the shield is removed and one of the ends of the small glass tube accompanying the outfit is introduced into the blister. The tube, both ends of which should be open, should be held so that the end inserted is higher than the other, to allow the serum to run into it. After the tube has been nearly filled, it is removed and the ends sealed by holding them a moment in a gas flame. Care must be observed not to heat the middle portion of the tube, and thus coagulate the serum. The tube so prepared is then placed in the wooden box and returned in the addressed envelope to a culture station, or mailed to the laboratory. A report on the results of the examination will be telephoned to the attending physician early on the following day, where his telephone number can be ascertained. Reports are mailed by I P.M. each day, and should reach their destination the same evening. Laboratory Technique. A culture of typhoid fever bacilli is obtained from an authenticated case of typhoid fever, and this must be selected with care. Not all races of typhoid bacilli give equal results, and by a process of selection a culture must be found that gives the best results in the largest number of cases. Having obtained a satisfactory culture it should be kept in a virile condition by frequent transfers to agar tubes. For use fresh bouillon cultures should be used, — that is, sub-cultures less than twenty hours old. The reaction of the medium shall be not far from the neutral point. A drop of the blood to be examined is placed upon a glass slip, with nine drops of sterile water around it, and the whole stirred with a sterile platinum wire until the blood has been well mixed through the mass. This gives a 1:10 dilution. Occasionally higher dilutions are used. A drop of this diluted blood is then added to a drop of the culture medium, containing the living typhoid bacilli. This gives a dilution of 1:20, the dilution generally used. The cover glass is then sealed with vaseline and placed under the microscope, using a one-sixth inch objective, and the material examined as a " hanging drop," at intervals for about half an hour. 320 TYPHOID FEVER. In a typical positive reaction the bacilli lose motility and group themselves in clusters, or clumps. This agglutination of the bacilli is indicative that the blood is derived from a person who has or who has recently had the disease. Agglutination may occur in some cases in high dilutions; in others, only in low dilu- tions. But low dilutions may sometimes show positive tests in the case of other diseases, and even in the case of well persons; hence the test is not always final and deciding. As a rule, however, positive tests obtained using a dilution of 1:20 indicate a positive diagnosis. For further data concerning this test, and the agglutinating eflfects of the paratyphoid bacillus, the bacillus of dysentery, etc., the reader is referred to the recent works on pathological bac- teriology. Ehrlich's Diazo Reaction in Urine. The presence in the urine of Ehrlich's diazo reaction for typhoid fever furnishes an early and valuable aid in the diagnosis of typhoid fever. The test is performed in the following manner: Equal parts of the suspected urine and the following solution (saturated solu- tion of sulphanilic acid in 5 per cent hydrochloric acid 40 parts; 0.5 per cent solution of sodium nitrite i part) are mixed and well shaken. On the addition of a few drops of ammonia a brilliant rose pink color should appear, if the case be one of typhoid fever. The twelve-hour sediment is also characteristic, consisting of a dirty gray lower layer and a narrower dark olive green upper layer. This reaction is present in the urine of a great majority of all cases of typhoid fever at some time in their course. It is found earlier than the Widal reaction in the blood, appearing on from the third to the sixth day of the disease. The intensity and date of appearance of the reaction appear to have no relation to the severity of infection. In a number of instances the diazo reaction has been present in undoubted cases of typhoid fever in which no Widal reaction was at any time obtainable from the blood. No case has so far been observed in which the Widal reaction was present and the diazo reaction absent. The reaction is present APPENDIX VI. 321 in its greatest intensity at about the tenth day of the disease. It often disappears at the end of the second week, and is almost invariably absent when complete defervescence is reached. In relapses the reaction usually reappears, but if the reinfection is mild, it may be absent. In second or third attacks of the disease, occurring after intervals of months or years, the reaction is present just as in primary attacks. It is also present in certain other conditions; these are severe scarlet fever and measles, acute miliary tuberculosis, and general sarcomatosis or carcinosis. With the exception of miliary tuberculosis, however, the above conditions are usually readily distinguishable from typhoid fever. Examination of the Blood for the Typhoid Bacillus. Coleman and Buxton's blood test is described on page 322. By the use of this test, the diagnosis of the disease can be made at an earlier stage than with the Widal test alone. APPENDIX VII. THE BACTERIOLOGY OF THE BLOOD IN TYPHOID FEVER. AN ANALYSIS OF 1602 CASES.^ By Warren Coleman, M.D., Professor of Clinical Medicine, Cornell University Medical College, and Assistant Visiting Physician to Bellevue Hospital, New York, and B. H. Buxton, M.D., Professor of Experimental Pathology, Cornell University Medical College, New York. During the last six years we have made bacteriological exami- nations of the blood in 123 cases of typhoid fever in the wards of the Second Medical Division of Bellevue Hospital. In 1904 we published an analysis of 604 cases of typhoid fever (for the most part collected from the literature) in which the blood had been examined bacteriologically. Seventy-five per cent of these cases, examined at all stages of the disease, showed the presence of the typhoid bacillus. Bacteriological examinations of the blood of typhoid and suspected cases have been made routine practice in many hospitals, and the number of cases reported to date, including our own, reaches a total of 1602. The present analysis includes all the cases in our former paper, except the reports of individual cases. Methods. We usually draw 10 cubic centimeters of blood into an all-glass syringe from a vein at the bend of the elbow. In our earlier experiments (1901 to 1903) we used broth flasks, putting 2 to 3 cubic centimeters of blood into each 100 cubic centimeters of broth. Later, on learning that Busquet and other French authors had had extraordinary success by using very large quantities of broth, we followed their method of dilu- ' From the American Journal of the Medical Scieftces, June, 1907. 322 APPENDIX Vn. 323 ting each cubic centimeter of blood in about 200 cubic centimeters of broth, but the results were not appreciably better than before. Since August, 1906, however, we have had very marked success with ox-bile, as recommended by Conradi. Ox-bile not only prevents coagulation, but inhibits the bactericidal action of drawn blood and affords an excellent culture medium for typhoid bacilli. Our tests on this point have fully confirmed the previous observations of Conradi, Kayser and others. The method followed has been to take ox-bile 90 cubic centi- meters, glycerin 10 cubic centimeters, and peptone 2 grams. The mixture is distributed into small flasks, 20 cubic centimeters in each, and sterilized. Three of these flasks are used for each examination, about 3 cubic centimeters of blood being run into each. The flasks are then incubated, and the next morning streaks are made from each flask over the surface of a litmus- lactose-agar plate. If microorganisms are present, a growth may be observed in flve or six hours. If the growth does not redden the medium and is found to be a bacillus resembling the typhoid organism, it is tested for the Widal reaction with immune serum. By this procedure we are often able to determine if the case is one of typhoid fever or not within twenty-four hours after drawing the blood. Of 1602 tabulated cases, 1197, or 75 per cent, gave a positive result. The examinations were made at all stages of the disease and by different methods. Since in our experience the bile method^ is the only one which may confidently be depended upon, such a large percentage of positive results goes far to prove that the bacillus is present in the blood in practically all cases of typhoid fever. Analysis of the Cases by Weeks. The day of the disease upon which the examination was made is mentioned in 1137 cases only. To be more exact, this represents the number of examina- tions, not of cases, for in many instances more than one examina- tion was made in a case. First Week. Of 224 examinations in the first week of the We have not tried the glucose method of Epstein. 324 TYPHOID FEVER. disease, 200 (8g per cent) were positive. The earliest positive result has been reported by Widal, who recovered the bacillus from the blood on the second day of the disease. The reported positive results become more frequent as the end of the first week is approached, only, we believe, because the disease is not sus- pected earlier, and the examinations made, or because the cases do not come under observation. Second Week. Of 484 examinations made in the second week of the disease, 353 (73 per cent) were positive. Third Week. Of 268 examinations made in the third week of the disease, 178 (60 per cent) were positive. Fourth Week. Of 103 examinations made in the fourth week of the disease, 39 (38 per cent) were positive. After the Fourth Week. Of 58 examinations made after the fourth week of the disease, exclusive of relapses, 15 (26 per cent) were positive. Very few statements are made concerning the clinical histories ojf the cases in and after the fourth week, though some of them are reported as severe and of long duration. As in our first analysis, the percentage of positive results is greatest in the first week and steadily declines thereafter. We have already called attention to the remarkably successful results of Busquet and others, who recovered the bacillus from the blood in approximately 100 per cent of their cases. Our results since the adoption of the bile method have been equally successful, standing out in marked contrast to those with broth. In all we have used this method in 34 cases. As a rule, the blood was examined as soon as a case of fever without obvious cause entered the hospital, and before the diagnosis Was estab- lished. Six of these 34 cases were diagnosticated ultimately as certainly not typhoid fever; 3 of the cases pursued the clinical course of typhoid fever, but gave neither a positive blood culture, nor a positive serum reaction against any member of the typhoid- colon group. In fact, after examinations of urine, feces, opsonic index, and injections of tuberculin, a satisfactory diagnosis could not be made. It seems only fair to exclude these cases. One APPENDIX VII, 325 case ran an eleven-day temperature, the maximum being loi degrees, but for the most part ranging between 99 and 100 degrees. The first blood culture was taken on the eighth day. There was a difference of opinion as to the diagnosis. The patient had an old tuberculous process at one apex. This case likewise may be fairly excluded. "We made three examinations of his blood. The remaining 24 cases were typhoid fever clinically and by serum reaction and all gave positive bacteriological results. The examinations were made from the fifth to the twenty-first day in a long-duration case. The various series oi cases in the table giving approximately 100 per cent of positive bacteriological results are too numerous to be accidental. They compel the conclusion that the typhoid bacillus is present in the blood in ever}- case of typhoid fever and that failure to recover it is due to error of technique. The diminishing percentages of the larger analysis in the later weeks of the disease do not indicate, then, that the bacillus has dis- appeared from the blood in the negative cases, but point rather to diminishing numbers of bacilli, whose presence imperfect methods have failed to reveal. All investigators except Conradi are agreed that the bacillus disappears from the blood at or about the time the temperature falls to normal. Conradi claims that the bacillemia persists into convalescence. We have repeatedly examined the blood in the last day or two of the febrile period and not once have we recovered the bacillus. Therefore, it seems probable that the typhoid bacillus is not only present in the blood in every case of typhoid fever^ but that it is present throughout the course of the disease, or at least to within a day or two of complete defer^'escence. The Significance of the Bacillemia. If future observations confirm the conclusion that the typhoid bacillus is present in the blood of every case of typhoid fever throughout its course, the current conception of the pathogenesis of the disease should be modified. Typhoid fever can no longer be regarded simply as an infection of the body with typhoid and related bacilli 326 TYPHOID FEVER. (Bacillus paratyphosus, etc.). The typhoid bacillus may be present in the body and actively growing, yet the patient not have typhoid fever. It has been shown, for example, that the bacillus may live and multiply in the intestine of healthy per- sons. The patient is infested and a menace to others, but is not infected. The number of cases of biliary infection with the typhoid bacillus, without a previous or existent typhoid fever, is fairly large and is increasing. At least two cases of cystitis, caused by the typhoid bacillus in persons without a history of typhoid fever, have been recorded. (There is little probability, however, of the absorption of endotoxins in any quantity in cholecystitis and cystitis). In the post-typhoid bone and other inflammatory lesions the lodgment and growth of the bacillus do not produce the characteristic symptoms of typhoid fever, in spite of the fact that large amounts of endotoxin should be lib- erated and absorbed when the abscesses are multiple. The very term used to describe these conditions, "post-typhoid," indicates that the typhoid fever per se has subsided. The tem- perature curve conforms to the so-called septic type. Therefore, it seems that to produce typhoid fever the bacillus must not only be present in the body and growing, but that it should grow in a situation whence it has free access to the blood. In our first paper we expressed the opinion that in typhoid fever the earliest and principal seat of infection is the blood, and that the disease should be regarded as a bacillemia. From the work done by one of us on the absorption of the typhoid bacillus from the peritoneum, and from the fact that in typhoid fever the lymph nodes and spleen contain such enormous numbers of bacilli, we are disposed to modify this view and to conclude that in typhoid fever the bacillus first finds its way from the alimentary tract to the lymphopoietic system, including the spleen, where it develops chiefly and from which it invades the blood stream. We think it doubtful whether the bacillus multiplies in the blood, but rather that its presence there represents simply an overflow from the lymph organs. Under this interpretation the presence of the bacillus in the blood does not. constitute a true septicemia. APPENDIX VII. 327 The absorption experiments above referred to also indicate that destruction of the typhoid bacilli proceeds most rapidly in the blood. This observation, together with the fact that the bacille- mia persists throughout the disease, suggests the following view of the pathogenesis of typhoid fever: That the disease is caused by the destruction of vast numbers of bacilli in the blood, with the liberation of their endotoxins, and the consequent reaction on the part of the host. When the endotoxins are liberated elsewhere in the body, e.g., in abscesses, the symptomatology is not that of typhoid fever. This conception of the nature of typhoid fever is borne out by analogy. It is known that Bacillus paratyphosus may infect the intestine and produce the clinical picture of gastro-enteritis, but that' when it invades the lymph organs and blood it produces a disease clinically indistinguishable from typhoid fever. Diplo- coccus lanceolatus and the various streptococci furnish similar analogies in that they produce different affections according to the regions they attack. There is another matter to which we would call attention in this connection. The idea still prevails in some quarters that the course of typhoid fever may be influenced and even shortened by the use of intestinal antiseptics. Such opinion is based on an erroneous conception of the nature of typhoid fever. After invasion of the body proper by the bacillus the battle-ground shifts from the intestines to the blood, and the employment of intestinal antiseptics with the idea of controlling the disease is, to say the least, irrational. The Relation of the Bacillemia to the Course and Types of the Disease. Course. The analysis of the cases in the various weeks of the disease suggests the following relation of the bacillemia to the course of typhoid fever; In the earlier stages the bacillus invades the blood in greatest numbers. Later, as the disease is approaching a favorable termination, the diminution in the num- ber of bacilli in the blood is simply an index of less active develop- ment in the lymphatics and spleen. If the disease in any case pursues a long-duration course, that beyond the usual three weeks, 328 TYPHOID FEVER. the bacillus may be recovered from the blood as long as the tem- perature persists. We have isolated the bacillus late in such cases repeatedly. There appears then to be a definite relation in the evolution of typhoid fever between the symptoms and the bacillemia. The increasing intensity of the symptoms in the earlier period of the disease corresponds to active growth of the bacilli. They invade the blood stream in increasing numbers and are there destroyed. Then comes the stationary period, when the ratios of growth and destruction appear uniform. The steep-curve period corresponds to a diminishing bacillemia, and defervescence to the complete disappearance of bacilli from the blood. In other words, the duration of the febrile movement is measured by the persistence of the bacillemia. As already stated, Conradi is the only investigator who claims that the bacil- lemia continues into convalescence. Ewing has expressed the opinion that "the degenerative changes in the liver, kidneys, and lymphoid organs, while initi- ated by the bacterial proteids, possess certain self-perpetuating tendencies," and therefore "typhoid fever is a combination of a specific bacterial intoxication and a somewhat peculiar auto- intoxication, the former element being more prominent early, the other later in the disease, but both developing simultaneously." We are unable to accept this conception of the pathogenesis of typhoid fever. It appears inconsistent with the facts developed by our studies. We maintain that exclusive of convalescence, which should be regarded as the period of repair, degenerative changes occur only in the presence of active growth and destruc- tion of bacilli. We have shown that convalescence is established immediately upon the disappearance of the bacilli from the blood, and there are reasons to believe that it is not interrupted except as the result of a fresh growth of bacilli. While the bacilli disappear from the blood at or just before defervescence, it is improbable that all the bacilli in the body have been destroyed. Otherwise, relapses and post-typhoid inflammatory lesions would be impos- sible. Unless then it can be shown that the symptoms of typhoid fever would persist after the complete destruction APPENDIX VII. 329 of all bacilli in the body, we think that Ewing's position is untenable. Types. The bacillemia apparently bears no relation to the type or severity of the disease except in so far as regards numbers of bacilli. The bacillus is found in the blood equally, but not with the same persistence, in the mild as in the severe cases, and in the cases of short as well as of long duration. We have found the bacillus, for example, in cases lasting ten, thirteen, and four- teen days, and on the twenty-seventh day of a long-duration case. The importance of the definite establishment of the nature of these short-duration cases can scarcely be overestimated from the epidemiological standpoint. The serum reaction has done much to clear up their diagnosis, but the final proof has remained for the bacteriological examination of the blood. We make only a brief reference to these cases here, as we shall deal with them at length in the near future. Relapses. The blood has been examined bacteriologically by various investigators in t,^ relapses. The typhoid bacillus has been recovered in 30 (90 per cent) of the cases. We suggested in 1904 that a relapse in typhoid fever is due to reinvasion of the blood by the bacillus. Reinvasion of the blood with destruction of the bacilli probably causes the symptoms of a relapse, but the underlying conditions which inaugurate active development of the bacilli after their growth has once been brought under control are unknown. We feel safe in asserting that a relapse is not due to reinfection with the typhoid bacillus from the intestine as the result of intestinal trauma brought about by dietary irregu- larities. We do not wish to intimate, however, that we believe the occurrence of a relapse is entirely independent of diet or to be understood as advocating a liberal diet in typhoid fever. We are not prepared as yet to express an opinion upon this subject. The Relation of the Bacillemia to the Senim^ Reaction. In our former paper we stated that it would seem likely on a priori grounds that the typhoid bacillus is always present in the blood before the serum reaction develops, for the reason that endotoxins 330 TYPHOID FEVER. should be liberated before the agglutinins could be formed. The following table clearly illustrates the truth of this conclusion: TABLE SHOWING RELATION OF BACILLEMIA TO SERUM REACTION. Author. Hirsh . Jochmann Roily Duffy Buxton and Coleman Bacillus Found and Widal Reaction Negative. 23 5 16 18 32 94 Of the 55 cases of Hirsh and ourselves, which showed the presence of the bacillus in the blood before the serum reaction could be obtained, 23 were in the first week, 26 in the second, and 6 in the third. The diagnostic value of these results in cases in which only one, or a few, serum tests have been made is important. A negative serum reaction may have no significance even in the third week of the disease. Moreover, Dr. Hastings has shown in some of our cases, especially those of short duration, that a positive serum reaction may be present for only two or three days. If the serum reaction had not been tested on those days, the result would have been recorded as negative throughout the disease. For the complete diagnosis of an obscure case by the serum reaction the tests should be made daily. Conclusions, i. The typhoid bacillus is present in the blood of every case of typhoid fever throughout its course. 2. The bacillemia in typhoid fever does not constitute a true septicemia, but it represents an overflow of bacilli from the lymphopoietic organs. 3. The clinical picture of typhoid fever results only from infec- tion of the lymphopoietic organs by the typhoid bacillus, with APPENDIX VII. 331 invasion of the blood stream and destruction there of vast num- bers of bacilli. 4. The endotoxins of the typhoid bacillus are not cumulative in action, and convalescence from the typhoid fever per se is established within a few days after the disappearance of the bacUli from the blood. APPENDIX VIII. EXAMINATION OF WATER FOR THE TYPHOID BACILLUS. The isolation of the typhoid fever bacillus from infected water is a matter of such difficulty that less than a dozen authentic cases of its finding are on record. Nevertheless, theoretically, it can be done, and it is not unlikely that the future may reveal some important developments in this direction. Savage, in his recent excellent vi^ork on the Bacteriological Examination of Water Supplies,^ has described various methods that have been used. These may be found also in Prescott and Winslow's '/Elements of Water Bacteriology." There are three steps involved in the process: — 1. Concentration, vs^hereby any typhoid bacilli that may be scattered through a large volume of water are brought together in a small volume within the compass of present methods of examination. 2. Isolation of the organism in pure culture. 3. Identification of the organism by the application of differ- ential tests. Concentration. A simple method of concentration is to filter a large quantity of the sample to be examined through a sterile Pasteur filter and brush the accumulated sediment into a small quantity of sterile water. This method is not satisfactory, as it increases all other kinds of bacteria in the same proportion. The use of the centrifuge has been recommended in place of filtration, but it has no especial advantage. Sometimes chemi- cals are used to produce a coagulent that during its precipi- tation will entangle the bacteria and carry them to the bottom. 1 Published by P. Blakiston's Son & Co. 332 APPENDIX VIII. 333 Anti-typhoid serum has also been used in a somewhat similar manner. Other methods depend upon the greater motility of the typhoid bacillus than most of the other bacteria likely to be found in water, and attempts have been made to separate the typhoid bacilli from the others by taking advantage of this characteristic. Various forms of enrichment methods have been suggested, that is, certain substances are added to the water with the object of facilitating the multiplication of the typhoid germ, or of inhib- iting the development of other forms. Phenol broth, caffeine, etc., have been used for this purpose; the latter with most suc- cess, but the sterilized ox-bile has been found to be more satis- factory than either. Isolation in Pure Culture. For this stage of the process some kind of solid medium is necessary in connection with the method of plate culture. Among the media used are nutrient gelatine, nutrient agar, semi-solid media composed of both gelatine and agar, phenol agar, lactose litmus agar, bile-salt agar, neutral red agar, etc. The Drigalski-Conradi agar is more satisfactory than any. Savage [loc. cit.] describes the use of this medium as follows: Drigalski-Conradi Agar. "This medium was primarily in- tended for the isolation of the typhoid bacillus from excreta; it is, however, of great value in water bacteriology. It is pre- pared as follows: " (i) Agar Preparation. — To 3 pounds of finely-cut beef, add 2 liters of water; allow the mixture to stand until next day. Boil the expressed meat-juice for one hour and filter; add 20 grams peptone sicca (Witte), 20 grams nutrose, 10 grams sodium chloride, boil the whole again for one hour and then filter. Now add 70 grams bar agar, boil for three hours (or one hour in the autoclave), renders Hghtly alkaline (indicator, litmus-paper), filter, boil for half an hour. "(2) Litmus Solution. — Litmus solution (Kubel and Tie- mann), 260 cubic centimeters; boil for ten minutes; add 30 grams of chemically pure milk-sugar and boil for fifteen minutes. Add 334 TYPHOID FEVER. the hot litmus milk-sugar solution to the liquid agar solution (cooled to 60° C); shake well; render it again faintly alkaline; then add 4 cubic centimeters of a hot sterile solution of 10 per cent water-free soda and 20 cubic centimeters of a freshly pre- pared solution of 0.1 gram crystal violet (B. Hochst) in 100 cubic centimeters warm sterile distilled water. The result is a meat- water peptone nutrose agar, containing 13 per cent litmus and o.oi per 1,000 crystal violet. The medium can be kept in tubes, or in small flasks containing enough for three or four plates. It is sufl&cient to sterilize once in current steam for thirty minutes." " The Petri dishes used should be large (diameter 15 to 20 centi- meters), and about 20 to 25 cubic centimeters should be poured into each. The medium should never be less than 2 millimeters thick. After pouring, the plate should remain uncovered for at least one hour, until the steam has evaporated and the agar is quite stiff. A sterile glass rod bent near one end at right angles is used for smearing the plates. After the plates are spread they should remain open for at least half an hour, until the agar surface is completely dry. This, according to the authors, is important, moisture causing the colonies to run together. Saprophytic air organisms are said not to grow, on account of the crystal violet, so that air contamination does not take place." " After fourteen to sixteen hours at 37° C. — twenty-four hours in some cases — the colonies can be distinguished from one another. The coli colonies are red, not transparent, and have a diameter of 2 to 6 millimeters, but considerable variation in size and degree of color are met with. The B. typhosus colonies are blue, with a violet tinge; they are transparent and resemble dew- drops, and have a diameter of i to 3 millimeters, seldom larger." Identification. This stage of the process consists in ascer- taining if the organism isolated conforms to the differential tests for typhoid fever in accordance with the characteristics set forth on page 314. Regarding this process Savage says: — APPENDIX VIII. 335 " It is now generally advocated that all suspicious organisms should first be roughly tested as to their ability to be agglutinated by typhoid serum in moderate dilution. If no agglutination takes place, they may be at once rejected. If a positive reaction is obtained, cultural tests are carried out, while a more exact series of agglutination tests is made. In this way it is possible to greatly lighten the labor of examining a large number of sus- picious colonies. The colonies under investigation are either at once examined or after subcultivation. For the first method a little of the colony is transferred to a cover-slip emulsified in a drop of broth, and an equal quantity of serum added, the whole test being carried out on the cover-slip. For the second method the colonies are inoculated into nutrient broth, and the agglu- tination tests performed next day, after growth has taken place. The latter is, on the whole, preferable. The broth cultures which show a positive result are then ready for further investigation; the others are rejected." " Great as are the improvements which have taken place in the facility with which typhoid bacilli can be isolated from specifically infected excreta, with none of the different methods can it be said that the isolation of the bacillus from an infected water-supply is other than a difficult and unsatisfactory procedure, and only under very favorable conditions can success be hoped for." "It is advisable to try several methods, and in the writer's opinion the following would probably be the most serviceable procedure: ''(a) Examine 5 to 10 liters by Drigalski's method." "(b) Take i liter of the water and precipitate the organisms by one of the precipitation methods. The precipitated organisms- are distributed over a large series of Drigalski-Conradi plates." "(c) Examine another liter by the caffeine method." " All suspicious colonies obtained from the three methods (and the total number may be large) are subcultivated into broth, and incubated at 37° C, until next day. They are all then examined in hanging drop, and those which show actively motile bacilli are tested with antityphoid serum. A fairly powerful 336 TYPHOID FEVER. serum should be available, and a dilution of not less than i per cent should be employed." " All those which fail to show agglutination are rejected, while those reacting are each subcultivated into litmus-milk, glucose neutral-red broth, and lactose-peptone solution." " All the organisms giving cultural characters in these media which accord with those of B. typhosus are fully worked out. The tests should include accurate and extended agglutination tests with highly dilute sera. Such organisms will usually be found to be very few in number." APPENDIX IX. PRESENT STATUS OF WATER ANALYSIS IN CON- NECTION WITH THE INVESTIGATION OF TYPHOID EPIDEMICS.! By Ernest C. Levy, M.D., Chief Health Officer, Richmond, Va. {Formerly Director of Laboratory of City Water Department.) The frequency with which the writer receives inquiries from physicians in regard to examining water for typhoid bacilli is sufl&cient ground for believing that a brief paper dealing with the subject here chosen will have a certain amount of usefulness. Knowing that where a given water is responsible for an outbreak of typhoid fever the bacilli of this disease must have been present in the water, and having only rather general ideas of the methods of bacteriological examination of water, what more natural than that the average physician should consider the actual finding of typhoid bacilli as the natural and crucial test in these cases? It is the object of this paper to show why this direct method of solv- ing the question is not applicable, and, furthermore, to point out briefly just what the water expert of to-day does in these cases, provided he can get his client to understand something of the matter — which end, in the writer's own experience, can always be accomplished by a plain statement of the facts in the case. The first difficulty connected with placing the responsibility for an outbreak of typhoid fever by means of direct bacterio- logical examination for the detection of B. typhi, lies in the fact that, assuming the water to have been the actual cause, it is ! Reprint from Virginia Medical Semi-Monthly, Nov. lo, 1905. 337 338 TYPHOID FEVER. impossible to get a sample of the right water for examination. The minimum period of incubation of typhoid fever is eight days, with ^n average period of two weeks. Hence, assuming a water- supply to become infected, it is not until two weeks later that a sufficient number of cases of the disease have developed to attract considerable attention, and allowing (a liberal estimate) a week more for the physician or health officer to reflect on the subject and get into communication with the bacteriologist, it is three weeks altogether before the investigation is started. It is self- evident that, unless the pollution is a continuous one (which is not usually the case) the failure to find typhoid bacilli at this late date cannot be taken as indicating that the water was not originally infected and gave rise to the outbreak. Coming now to the question of the actual examination of water for B. typhi, it is not at all difiicult to explain why our methods are so imperfect. In almost every instance where a stream becomes infected by typhoid bacilli this stream receives at all t^mes the fecal dejecta of a number of persons, and it is only when one of these individuals develops typhoid fever that the bacilli of this disease are added to the water, along with the continued discharges of a number of unaffected persons. Now, even the dejecta of the typhoid patient himself contain B. coli (the normal inhabitant of the intestinal canal) in probably greater numbers than B. typhi, while still larger numbers of the former organism continue to enter the stream in the stools of the healthy inhabi- tants of the watershed. We must, therefore, realize that almost invariably a water which has become infected with B. typhi has, along with these organisms, an immensely larger number of B. coli, the only exception to this being where a water has become infected by the urine of a typhoid patient but is otherwise unpol- luted — obviously a most unusual condition. Besides this, a water so polluted as the one we are considering in our typical case is certain to contain large numbers of bacteria of other kinds, so that for every typhoid bacillus present there are probably an immense number of bacteria of other varieties. Let us assume a concrete illustration for the sake of making APPENDIX IX. 339 clearer the problem which confronts the bacteriologist in these cases. A water would surely be seriously infected if each glass- ful contained 20 typhoid bacilli, yet, since an ordinary drinking glass holds about 200 cubic centimeters, in this case there would be only a single typhoid bacillus in each 10 cubic centimeters of the water. Such a water would almost certainly contain at least 200 bacteria of other kinds per cubic centimeters or 2000 in the 10 cubic centimeters. In our hypothetical case, therefore, for each typhoid bacillus there would be 2000 other bacteria. Under such conditions let us see what would be the chance of finding typhoid bacilli. In the routine method of plating on gelatine, it would be necessary to make ten plates of one cubic centimeter each in order to get a single colony of B. typhi (assum- ing the typhoid bacilli to be evenly distributed through the water), and after all the colonies have developed there are no character- istics by which a typhoid colony can be picked out on sight, while it is obviously impossible to make the necessary detailed study of so large a number of colonies as would be necessary to identify the typhoid colony from others resembling it. If instead of gelatine we use agar and incubate at 37° C, a smaller number of total colonies will develop, but even here it would be impos- sible to tell if one of these was B. typhi, except by a most tedious and practically impossible detailed study of hundreds of colonies. Evidently, then, simple plating is not to be considered as a means of detecting typhoid bacilli in water, and we are brought to look into whether there can be found some differential method which will allow the typhoid bacilli, if present, to develop, while restraining the numerous other forms which must always be con- ceived as being present. Many methods of this sort have been suggested from time to time, but not one of them is to be relied on, the chief difl&culty being that the colon bacillus, always present, is much hardier than the typhoid bacillus, and no means are yet known of inhibiting the growth of the former and still permitting the latter to proliferate. It must be made clear that there is no difl&culty in differentiating B. coli from B. typhi when cultures 340 TYPHOID FEVER. of each are at hand, but the problem is to obtain the latter at all in the presence of large numbers of the former and large num- bers of bacteria of still other kinds. Recognizing that one of our difficulties is the fact that so large an amount of water must be examined to find even a single typhoid bacillus, it has been recommended to pass a considerable amount of water through a porcelain filter and take for examina- tion some of the scrapings from the filter, which will then con- tain, in small bulk, all the bacteria originally present in the water. As a matter of fact this in no wise lessens our troubles, for we now have an enormously increased number of B. coli and other bacteria to deal with, and this, as pointed out above, is our greatest difficulty after all. If, following any of the very doubtful methods which have been proposed, the bacteriologist at last secures what he sus- pects may be a culture of B. typhi, the further task of making certain of this point is by no means an easy one. B. typhi is distinguished largely by negative characteristics, both morpho- logical and Cultural, nor is it pathogenic in a true sense for any of our laboratory animals. Even the serum reaction, lauded as specific when first brought, has come to be recognized as a test demanding the utmost care in technique and in inter- pretation. Owing, then, to the difficulties above hastily outlined, an expe- rienced man in this branch of sanitary science will not undertake to examine a water at all for B. typhi, or at any rate he will stake nothing on the result. But,' while the problem cannot be solved in this direct manner, still it is possible in nearly every in- stance to arrive at results in a different way, and this true method of approach is, after all, of far greater value than a mere finding or not finding of typhoid bacilli in the water could possibly be. The correct way of solving the problem, as matters stand, is to make a thorough study of each specific case which arises, along well recognized lines. Briefly, this includes a sanitary survey of the watershed, a study of the epidemic itself, and a, bacterio- APPENDIX IX. 341 logical and chemical examination of the water. The sanitary survey is to be regarded as an indispensable factor in every case of importance, and as such it cannot be entrusted to anyone who has not had special training in just this kind of work. Each case presents its own peculiarities, and some point which it is impossible to foresee may give the due to the whole situation. Along with this sanitary survey, inquiry should be made into the special features of the epidemic itself. To do this thoroughly is the work of weeks, or even months in the case of large com- munities and extensive epidemics, but sufficient information for practical purposes may frequently be gained in a few hours of intelligent study in smaller communities, especially if the local physicians' records are fairly complete. This visit to the seat of the trouble, moreover, enables us to judge of just what samples we wish to have for analysis and to collect these under the best conditions and with proper precau- tions. It also enables us to start certain parts of the bacterio- logical work on the spot, which is a matter of no little moment if at some distance from the laboratory. The tests which will be applied are, in a broad sense, for the determination of fecal pollu- tion in general. Both chemistry and bacteriology are called upon, but the chief thing is the detection of intestinal bacteria. After getting together all the facts both of the analysis and of the sanitary survey and special study, a careful consideration of all the data thus available will, in almost every instance, lead to a thoroughly trustworthy opinion. It is just at this part of the work that judgment and experience come most into play. The data at hand are to an expert in this line what the previous history, symptoms and physical signs are to the physician in arriving at a diagnosis, and each reaches his final opinion by a careful weighing of all the evidence and not by blind reliance upon any isolated fact. This simile may be carried further. Certain cases of disease may be diagnosticated by a laboratory test of material secured from the patient, as, for instance, is possible by a sputum examina- tion in cases of pulmonary tuberculosis, but no physician would 342 TYPHOID FEVER. care to take the responsibility of treating a case of consumption merely on the evidence thus afforded, without examining the patient and learning a great deal about his general condition and his environment. Just so, the water expert may often be able to decide by analytical methods whether or not the water is polluted, but knowledge so gained is always of a general char- acter, and personal study of the case on the ground is necessary for the correction of existing conditions. We may apply our simile, furthermore, to negative cases. Where a sputum exarnination does not show tubercle bacilli, but where the patient is nevertheless seriously ill, the examination will show little of what the real condition is. So with water, finding that, so far as a mere laboratory examination can ever show, the water is all right, but if, in spite of this, typhoid fever has been very prevalent, our examination is of value merely by the probable elimination of the water as a cause, but it has thrown no light whatever on what is responsible for the trouble. And, again, our work would be incomplete and misleading where the water was only one of several causes. By means of a personal survey, if the water was found not responsible, or responsible only in part, the search would be continued to arrive at every factor in the case. The main points may be briefly summed up as follows: (i) No satisfactory method is known for the detection of B. typhi in water. (2) Were such a method known, it would be of limited appli- cation on account of the fact that when an outbreak of typhoid fever leads to an investigation, the water supposed to have been infected is no longer available for examination. (3) Although the direct detection of B. typhi in water is impos- sible, yet the importance of bacteriological and chemical exami- nation of the suspected water must not be underestimated, but it should be combined with a thorough sanitary survey of the field, and a competent study of the phases of the epidemic. This will almost invariably solve the question whether the outbreak was caused by drinking-water. APPENDIX IX. 343 (4) This method of attacking the problem has the further advantage of throwing light on the sanitary quahty of the water in question apart from the special outbreak of typhoid fever, and, moreover, if it is found that the water is not responsible, or respon- sible only in part, full information will be gained along many lines, thereby suggesting the steps to be taken for future protection. APPENDIX X. THE VIABILITY OF THE TYPHOID BACILLUS UNDER NATURAL CONDITIONS.^ By Herbert D. Pease, M.D., Director New York State Hygienic Laboratory, Albany, N. Y. Simple of solution as this subject may appear to be to the unin- itiated, it is in reality one which has occupied the attention of bacteriologists and engineers for many years. However, upon certain aspects of the subject much has apparently been accom- plished in the last five years. " That the subject is of importance is quite evident to those who have followed the results of the studies of outbreaks of typhoid fever published during the last half decade. Such studies are demonstrating more and more that epidemics of the disease are caused by unusual combinations of natural and artificial condi- tions which cannot be foreseen or foretold, and which can only be prevented by directing special attention in two directions — first, toward the great public improvements in water purification, sewage disposal and milk production and distribution; and, sec- ondly, toward the proper hygienic management of each case of the disease. This review will not attempt to consider the latter aspect of the subject in which the relation of the typhoid bacillus to the infected patient would naturally come under discussion, but will deal with the fate of the typhoid bacillus as it passes from such a patient out into nature. I will first discuss some of the available evidence as to the fate * From Medical Review of Reviews, New York, September, 1907. 344 APPENDIX X. 345 of the bacillus typhosus when deposited in various kinds of natural soils or earths. Firth and Horrocks ^ reviewed the work done on this phase of the subject down to 1902, and concluded that the results were too contradictory and unsatisfactory to be accepted. They took to demonstrate the fate of bacillus typhosus in moist and dry soils of various kinds under natural conditions, such as the presence and absence of direct sunlight and the effect of washing of the soils by rains. Their results are of great interest and importance. They found that the typhoid bacillus had a long life, of at least two months, in the various soils when the same were kept moist; that they showed no tendency to multiply in such soils or to grow in any direction; that they could be washed by water for at least 18 inches through fine, closely packed earth without cracks or fissures; that the presence or absence of organic matter or sewage in the soil did not materially affect its existence, either favorably or otherwise; that when any of the kinds of typhoid-contami- nated soils or earths were allowed to dry so as to form dust, the typhoid bacillus could be found living in it after 25 days, and that the dust blown from such dirt contained living typhoid bacilli. They likewise found that 122 hours of direct sunlight during 21 days was not sufficient to kill the typhoid bacillus present in soils. They also ascertained that the freezing of soil containing typhoid bacilli for periods of several days did not completely kill these bacteria. In none of the experiments made by these authors were attempts made to determine quantitative viabiHty as well as qualitative, and they are open to this objection. RuUmann ' found that the typhoid bacillus lived for at least a year and a half in otherwise sterile earth and gravel, but in that time had died out in sand. The numbers were greatly reduced, ' Firth and Horrocks: British Medical Journal, 1902, Vol. 92, p. 936.' ^ Rullmann: Centralblatt jur Bakteriologie, Erst Abt; Originale, XXXVIII, p. 380. 346 TYPHOID FEVER. however, in all, and the reduction was greater in the earth than in the gravel. Levy and Keyser ^ claim to have found living typhoid bacilli in clayey garden soil, which had been manured with the contents of a water-tight privy into which typhoid-infected stools had been deposited five months previously. From the results of these investigators, it would appear that all forms of moist human excrement, dirt, soil, sand, or gravel favor the viability of the typhoid bacillus, while even the same materials in a dry state support its existence for a considerable period, often over a month. It would also appear that freezing and direct sunlight have but little eifect upon the typhoid bacillus in soils, and that they can be washed for a considerable distance through well-packed earth and retain life. These conclusions of laboratory investigations are in entire harmony with the known facts concerning the origin of numerous epidemics of typhoid fever. In many of these cases it has been shown that typhoid discharges thrown upon the surface of the ground, or buried superficially during the winter, and which have remained in these locations for several months, undergoing freezing and more or less exposure to sunlight, have finally been carried into waters for potable purposes and have produced wide- spread epidemics. The New Haven, Conn., epidemic of 1901 was brought about in this way. Many other instances of a . similar kind could be quoted. When we come to the consideration of the experiments on the viability of the typhoid bacillus in water and sewage, the results are found to be somewhat different. In water the typhoid bacillus is subject to conditions and agen- cies of a physical, chemical or biological character. The physical agencies, such as gravity, sunlight and temperature, probably play a most important part in rendering water an unfavorable soil for the existence of the typhoid bacillus, but chemical agencies, such as the presence of metals or inorganic compounds, absence ^ Levy and Kayser: CentralblaU fur Bakteriologie, Erste Abt.; Orig., XXXIII, 489. APPENDIX X. 347 of oxygen and usual organic matter, likewise play a considerable role in this direction under certain circumstances, while the bio- logical agencies, such as the indirect or direct antagonism of other bacteria and of protozoa, likewise aid materially in the destruction of these pathogenic bacteria. One of the most potent factors in the elimination of typhoid bacilli from water is sedimentation. The effect of this agency is so well known and consistently recognized that it is not necessary to dwell upon it at length. Sedimentation was the agency to which Jordan ^ attributed a large part of the purification of the Chicago Drainage Canal and the Illinois river. This force, of course, acts in inverse proportion to the amount of current or motion in a body of water. Bissell ^ has stated that he found as many colon bacilU in the waters of Niagara River below Niagara Falls as above it. The fate of the typhoid bacillus after it has reached the bottom of a body of water has not been studied to any great extent. The solution of the problem has not great practical importance except in connection with the matter of the pollution of edible shellfish, such as oysters and clams. Savage ^ studied the effect of what he calls tidal mud upon the typhoid bacillus, and found that the latter can survive fairly readily for two weeks in tidal mud, but after this period their numbers rapidly diminish. He believes that the examinations of mud when obtainable form a better index of the pollution of a stream or other body of water than the examination of the water itself. That direct sunlight, and even diffuse daylight, had a marked destructive effect on typhoid bacilli, as well as other bacteria in water, has been well recognized since the early work of Buchner. He concluded that direct sunlight is a more potent factor in redu- ^ Jordan: Journal of Experimental Medicine, 1900, V, 271. * Bissell: Proceedings American Public Health Association, 1903, XXIX, 360. ^ Savage: Journal oj Hygiene, 1905, Vol. 5, p. 146. * Buchner: Centralblatt fur Bakteriologie, XI, 781. Quoted by Wheeler: Journal of Medical Research, 1906, XV, 277. 348 TYPHOID FEVER. cing the number of bacteria in natural bodies of water than sedi- mentation. Procacci exposed water in deep cylinders to the nearly vertical rays of the sun, and found that after three hours the water in the cylinders was sterile to the depth of one foot, while at a depth of two feet the typhoid bacilli were unaffected. Clark and Gage ^ found that typhoid bacilli in a thin layer of water were destroyed by the direct sunlight in one hour, and that when they were exposed in bottles of water their extinction was accomplished in five hours. Wheeler^ has shown that diffuse daylight has a detrimental action on bacillus typhosus in waters contained in glass bottles. Weinzirl ' has recently shown that direct sunlight has an even more powerful germicidal action than has been shown by previous experimenters. The defects in former methods of testing were caused by the deflection, reflection and absorption of the sun's rays by the glass vessels, etc., used to maintain the specimens free from contamination by foreign bacteria. While sunlight unquestionably has a very destructive effect upon typhoid bacilli in water under most natural conditions, its failure to seriously affect these bacteria when the latter were placed in earth and dirt, as shown by the Firth and Horrock's tests, already referred to, indicates that there must be some other condition than the mere presence of the sunlight which gives material aid to its disinfecting action when the bacilli are in water. This will be again referred to when the effects of the presence and absence of dissolved oxygen in the water is taken up for consideration. The effects of different degrees of temperature on typhoid bacilli in water is most interesting. As is well known, the opti- mum temperature for their growth in culture media is that of the human body. ^ Clark and Gage: Annual Report Massachusetts State Board of Health, 1902, 275. ' Wheeler: Journal of Medical Research, 1906, XV, 269. ' Weinzirl : Journal Infectious Diseases. Supplement III, May, 1907. APPENDIX X. 349 Clark and Gage ^ found that -when in water it could resist a temperature of 80° C. for five minutes. However, they found that the optimum temperature for the \'iability of the bacillus in water was 20-22° C, or the so-called room temperature, and that 37° C, or the body temperature, exerted a detrimental effect. This has been confirmed by Conradi and Bolton ^ and by Wheeler,^ who, in addition, has shown that the room tempera- ture is more favorable to typhoid bacilli in water than is that of the refrigerator. He also states that temperatures approximating 0° C, and 32° F., are decidedly detrimental to these bacteria in at least three classes of water. Smith and Swingle * state that the critical temperature for the life of bacteria is about 0° C. One of the first tests of the effect of actual freezing upon bacillus typhosus was made by Prudden ^ in 1887. By the methods of testing which he used, namely, to freeze small amounts of water containing typhoid bacilli, he found that they lived in ice for 103 days. Later Park ^ repeated these experiments, but made quantita- tive as well as qualitative tests, and determined that the decrease in the numbers of the typhoid bacilli was exceedingly rapid during the first few days or weeks. At the end of three weeks less than I per cent were alive. Zeit ^ also repeated Prudden's experiment, and found that the typhoid bacilli were completely killed by freezing in 24 hours. Clark and Gage ^ operated with much larger volumes of both water and sewage. They have shown that the typhoid bacillus * Clark and Gage : Loc. Cit. ' Conradi and Bolton: Centralblati Jur Bakterwlogw, Erste Abt.; Orig., XXXW, 203. 3 WTieeler: Loc. Cit 4 Smith and S-ningle: Science, 1905, N. S., Vol. XXI, 481. * Prudden: Medical Record, 1887, 31, p. 341. ^ Park: Journal Boston Society Medical Science. ^ Jordan, Russell and Zeit: Journal of Infectious Diseases, 1904, I, 660. 8 Clark and Gage: Annual Report Massachusetts State Board of Health, 1902, 280. 350 TYPHOID FEVER. is killed rapidly in both the freezing process and by low tem- peratures just short of freezing. Many other experiments were made by them in which the typhoid bacillus was not introduced into the operations, but from the results of which conclusions as to the effect of freezing on the typhoid bacillus in water under natural conditions might with propriety be drawn. Thus they found that from 95 to 99 per cent of all the water bacteria, and all of the colon bacilli in either water or sewage, were removed by freezing. Samples of ice, and water under the ice, were taken by them from the polluted Merrimac River at points varying from three to eight and a half miles from the outlets from the sewers of a city of 90,000 inhabitants, and the ice had less than 0.3 per cent of the number of bacteria present in the water under it, and no colon bacilli were found in the ice. Clark ^ believes that in the process of freezing, the bacteria, along with particles of dirt, substances in suspension and some of the mineral constituents of the water, are expelled into the underlying water. He thinks, therefore, that the physical con- dition of the water while freezing is of great importance, as this expulsion takes place most satisfactorily when the water is quiet. Wheeler ^ obtained very similar results to those quoted in his laboratory tests of freezing typhoid bacilli in relatively small amounts of water. However, he does not consider Clark's explanation of the causation of the decrease in the numbers of bacteria in ice by expulsion as the correct one. He floated porce- lain capsules containing some of the same typhoid-inoculated water as was in the pails they were floating in, and found that the typhoid bacilli were killed as completely and rapidly in the cap- sules as in the surrounding ice. He also obtained about as com- plete destruction of the typhoid bacilli in the underlying water in the pails as in the ice. However, his work was done on small ' Clark: Proceedings American Public Health Association, XXVII, 204. » Wheeler: Loc. Cit. APPENDIX X. 351 volumes of water, previously sterilized by heat and laboratory conditions, while Clark's and Gage's work had been done under more natural conditions, in large volumes of water. Wheeler obtained samples of ice and water from Lake Cham- plain at distances varying from 30 to several hundred feet from the sewer outlets of the city of Burlington. In the samples col- lected but 30 feet from the sewer outlets there were microscopic evidences of sewage. Bacillus coli was not found in any of the ice samples, but was present in large numbers in the underlying water. Smith and Swingle ^ obtained a percentage destruction of over 91 in their laboratory freezing tests of the typhoid bacillus in bouillon. They believe, from freezing experiments done on other species of bacteria, that when a few organisms out of a culture show a special resistance to the freezing, that this resistance is due to absence of water in the protoplasm of those particular bacteria, and that they behave, therefore, like endospores, although the species may be one in which no endospores are to be found. Prudden, Park and others quoted found a small percentage of the typhoid bacilli in their cultures more resistant than the majority, and this endospore-like formation may be the expla- nation. All the authors unite in the conclusion that repeated freezings and thawings are more destructive to typhoid bacilli than the single freezings. There exists one reported instance in which not only was typhoid fever apparently transmitted to well persons by means of ice, but in which the investigators believed that they isolated typhoid bacilli from the ice in question. Hutchins and Wheeler^ reported the occurrence of 39 cases of typhoid fever in the St. Lawrence State Hospital at Ogdens- burg, N. Y., under conditions which led them to state with some degree of certainty that the disease was due to the use of ice taken from the St. Lawrence River. ^ Smith and Swingle: Loc. Cit. * Hutchins and Wheeler: American Journal Medical Science, 1903, Vol. 126, p. 680. 352 TYPHOID FEVER. They examined clear ice taken from the river five months pre- viously, which had been stored in one particular icehouse, the ice from which they had suspected as being the cause of the disease. In this ice were particles of dirt, and from these they isolated in pure culture several colon bacilli, and one which they considered bacillus typhosus. If Clark's theory concerning the elimination of particles of dirt, etc., from still water as it freezes is correct, and it is generally accepted, then this ice must have been formed when the water was in active motion, or the ice was flooded with the infected water and opportunities for the exclusion of the dirt prevented, or under some other very unusual condition. Ice had been cut from this location for the twelve years prior to the outbreak, and no typhoid fever traceable to it had been observed. It is of special significance that all the ice suspected of causing the disease came from one particular icehouse, although all were filled with ice from the same general location. The conclusion would seem to be irresistible that the pollution of this ice came about in some very special manner, the true nature of which the authors were unable to determine. Hill,^ in a report on the ice supply of the city of Boston, remarks that the purification of polluted water, which takes place during the process of freezing and including the subsequent three weeks, is equivalent to the filtration of that water by the most efficient slow sand filters. This opinion is in harmony with those expressed by Sedgwick^ and others. But little is known of the effect, if any, of the natural mineral constituents of water upon the typhoid bacillus, and it is not intended to here discuss the subject of the effect of the artificial addition of inorganic elements or compounds, such as copper sulphate, for the destruction of bacteria. The oxygen content of a given water containing typhoid bacilli is undoubtedly a factor of the greatest importance in relation to ^ Hill: Boston Medical and Surgical Journal, 1901, CXLV, 557. * Sedgwick: "Sanitary Science," 1905. APPENDIX X. 353 the viability of these organisms, but it has as yet received but little attention. Whipple and Mayer ^ have, however, clearly shown that the absence of dissolved oxygen has a most decided and rapid detri- mental effect upon typhoid bacilli in both water and bouillon. They question whether this fact has been given the consideration which it deserves in the interpretation of the results of laboratory experiments upon the viability of this organism. Experiments in which small amounts of water, sewage or bouillon, sterilized by heat, are utilized should certainly take into consideration the question of the lack of oxygen in such liquids. The difference in resistance of the typhoid bacillus in soils and in liquids under apparently similar physical conditions, as already noted, may possibly be due to a greater amount of oxygen in the soils than in the liquids. This conception of Whipple and Mayer is of the greatest importance, as it involves the question of the effect of the almost total lack of oxygen in the effluent of septic tanks upon the typhoid bacilli which are present in most raw sewages. If typhoid bacilli cannot exist for more than one or two days in the septic tank it is a fact of the utmost importance. The relation between the presence of organic matter in water and the viability of the typhoid bacillus is likewise an important matter. In the early days of bacteriology Bolton showed that in water repeatedly redistilled and inoculated with typhoid bacilli, so as to avoid introducing organic matter, the typhoid organisms died out rapidly. Wheeler^ also shows that the less organic matter present in water the less favorable the influence upon the viability of the typhoid bacillus. By far the most extensive and valuable series of tests made upon this phase of the subject were those of Jordan, Russell and ' Whipple and Mayer: Journal of Infectious Diseases, 1906, Supple- ment II, p. 76. ^ Wheeler: Loc. Cit. 354 TYPHOID FEVER. Zeit,^ and later of Russell and Fuller.^ They tested the effect of natural conditions, excluding sunlight, upon celloidin, agar or parchment capsules, to which typhoid bacilli placed in various relatively unpolluted and polluted waters and sewage were like- wise added, and in which also the capsules were then floated. All possible grades and combinations from relatively pure waters to sewage inside these permeable sacs to sewage and rela- tively pure waters outside of them, and varying conditions from those done in nature to those in the laboratory were utilized in these tests. The authors conclude that in relatively pure waters, of a surface character, the typhoid bacillus is capable of retaining its vitality for about eight days. When the typhoid bacillus was inoculated into sewage it com- pletely disappeared in five days, and even in two or three days the majority of the organisms were killed off. They believe, therefore, that the typhoid organism in natural sewage does not live as long as it will in relatively pure water. They believe that the activity of the saprophytic bacteria in the sewage and polluted water plays a considerable role in this rapid destruction of the typhoid organism. However, the most convincing work on this aspect of the subject has been done by Frost,^ working with a similar technique of celloidin sac contain- ing typhoid-inoculated fluids, with growths of saprophytic bac- teria in the water, and bouillon in which the sacs are placed. The saprophytic bacteria he used were obtained from garden earth, street dust, sand and various waters. In many tests the soils themselves were inoculated into liquid surrounding the sacs. Frost found that the typhoid bacilli were rapidly killed in these sacs by thermostabile products of the growth of certain soil bac- teria (B. vulgatus, B. vulgaris. Pa. fluorescens and Pa. putida), which acted best at body temperature, but which were appar- * Jordan, Russell and Zeit: Loc. Cit. ^ Russell and Fuller: Journal of Infectious Diseases, 1906, Supplement II, p. 40. ^ Frost: Journal of Infectious Diseases, 1904, I, 599. APPENDIX X. 355 ently uninfluenced by other conditions. They operate, however, only when these bacteria are grown with or slightly in ad- vance of the typhoid bacillus. These thermostabile substances undoubtedly, therefore, play directly a large part in the .destruc- tion of typhoid bacilli in water and sewage under natural con- ditions. Frost was unable to explain their very feeble action at low temperatures; nor is there any explanation as yet offered as to why they do not act more promptly on typhoid bacilli in soils. It may be possible that they operate more strongly in the absence of oxygen. Frost was not specially clear on this point. Wheeler ^ found a harmless saprophytic bacillus carrotoverus which actually stimuilated the development of the typhoid bacillus when sown with it. Huntemiiller ^ has shown that various low forms of protozoa are capable of feeding upon typhoid bacilli. Klein ^ has shown that normal oysters, clams and other shell- fish, when grown in unpolluted waters, do not contain bacillus coli or sewage bacteria in their intestinal canals, but that when placed in sewage-polluted waters they become badly contaminated by such organisms. However, if they are removed from such polluted waters and kept under favorable conditions, they have the power of freeing themselves from both these colon and typhoid bacilli previously taken in. The rate at which this is accomplished depends upon the severity of the pollution. ^ Wheeler: Loc. Cit. ' Huntemuller: Archiv fur Hygiene, 1905, LIV, 89. ' Klein: Lancet, 1905, Vol. 168, p. 1133. APPENDIX XI. TYPHOID FEVER IN UNITED STATES ARMY CAMPS. {From the Report on the Origin and Spread of Typhoid Fever in the United States Military Camps during the Spanish War of i8q8, by Dr. Walter Reed, Dr. Victor C. Vaughan ajid Dr. Edward O. Shakespeare. ) General Statements and Conclusions. 1. During the Spanish War of 1898 every regiment constituting the First, Second, Third, Fourth, Fifth and Seventh Army Corps developed typhoid fever. 2. More than 90 per cent of the volunteer regiments developed 'typhoid fever within eight v^^eeks after going into camp. 3. Typhoid fever developed also in certain of the regular regi- ments within three to five weeks after going into camp. 4. Typhoid fever became epidemic both in the small encamp- ments of not more than one regiment, and in the larger ones consist- ing of one or more corps. 5. Typhoid fever became epidemic in camps located in the North- em as well as in those located in the Southern States. 6. Typhoid fever is so widely distributed in this country that one or more cases are likely to appear in any regiment within eight weeks after assembly. 7. Typhoid fever usually appears in military expeditions within eight weeks after assembly. 8. The miasmatic theory of the origin of typhoid fever is not supported by our investigations. 9. The pythogenic theory of the origin of typhoid fever is not supported by our investigations. 10. Our investigations confirm the doctrine of the specific origin 01 typhoid fever. 356 APPENDIX XI. 357 11. With typhoid fever as widely disseminated as it is in this country, the chances are that if a regiment of 1300 men should be assembled in any section and kept in a camp the sanitary conditions of which were perfect, one or more cases of typhoid fever would develop. 12. Typhoid fever is disseminated by the transference of the excretions of an infected individual to the alimentary canals of others. 13. Typhoid fever is more likely to become epidemic in camps than in civil life because of the greater difl&culty of disposing of the excretions from the human body. 14. A man infected with typhoid fever may scatter the infection in every latrine in a regiment before the disease is recognized in himself. 15. Camp pollution was the greatest sin committed by the troops in 1898. 16. Some commands were unwisely located. 17. In some instances the space allotted the regiments was in- adequate. 18. Many commands were allowed to remain on one site too long. 19. Requests for change in location made by medical officers were not always granted. 20. Superior line officers can not be held blameless for the unsani- tary condition of the camps. 21. Greater authority should be given medical officers in questions relating to the hygiene of camps. 22. It may be stated in a general way that the number of cases of typhoid fever in the different camps varied with the methods of disposing of the excretions. 23. The tub system of disposal of fecal matter as practiced in the Second Division of the Seventh Army Corps is to be condemned. 24. The regulation pit system is not a satisfactory method of disposing of fecal matter in permanent camps. 25. In permanent camps, where water carriage cannot be secured, all fecal matter should be disinfected and then carted away from the camp. 26. Infected water was not an important factor in the spread of typhoid fever in the national encampments in 1898. 358 TYPHOID FEVER. 27. To guard against the contamination of the water supply, troops in the field should be provided with means for the sterilization of water. 28. Flies undoubtedly served as carriers of the infection. 29. It is more than likely that men transported infected material on their persons or in their clothing and thus disseminated the disease. 30. Typhoid fever, as it developed in the regimental organizations, was characterized by a series of company epidemics, each one having more or less perfectly its own individual characteristics. 31. It is probable that the infection was disseminated to some extent through the air in the form of dust. 32. A command badly infected with typhoid fever does not lose the infection by simply changing location. ^^. When a command badly infected with typhoid fever changes its location it carries the specific agent of the disease in the bodies of the men, in their clothing, bedding, and tentage. ■ 34. Even an ocean voyage does not relieve an infected command of its infection. 35. After a command becomes badly infected with typhoid fever, changes of location, together with thorough disinfection of all cloth- ing, bedding, and tentage is necessary. 36. Except in case of the most urgent military necessity one command should not be located upon the site recently vacated by another. 37. The fact that a command expects to change its location does not justify neglect of proper policing of the ground occupied. 38. It is desirable that the soldier's bed should be raised from the ground. 39. In some of the encampments the tents were too much crowded. 40. Medical officers should insist that soldiers remove their outer clothing at night when the exigencies of the situation permit. 41. Malaria was not a prevalent disease among the troops that remained in the United States. 42. The continued fever that prevailed among the soldiers in this country in 1898 was typhoid fever. 43. In addition to the recognized cases of typhoid fever, there APPENDIX XI. 359 were many short or abortive attacks of this disease which were generally diagnosed as some form of malarial fever. 44. While our examinations show that coincident infection with malaria and typhoid fever may occur, the resulting complex of symptoms are not sufficientiy well defined and uniform to be recog- nized as a separate disease. 45. About one-fifth of the soldiers in the national encampments in the United States in 1898 developed typhoid fever. 46. Army surgeons correctly diagnosed about half the cases of typhoid fever. 47. The percentage of death among cases of typhoid fever was 7.61. 48. When a command is thoroughly saturated with typhoid fever it is probable that one-fourth to one-third of the men will be found susceptible to this disease. 49. In military practice typhoid fever is often apparently an intermittent disease. 50. The behef that errors in diet with consequent gastric and intestinal catarrh induce typhoid fever is not supported by our investigation. 51. The behef that simple gastro-intestinal disturbances predis- pose to typhoid fever is not supported by our investigation. 52. In a considerable per cent (a httle more than one-third) of the cases of typhoid fever which are recorded as having been preceded by some intestinal disturbance, the preceding illness was so closely followed by typhoid fever that we must regard the former as having occurred within the period of incubation of the latter. 53. More than 90 per cent of the men who developed typhoid fever had no preceding intestinal disorder. 54. The deaths from typhoid fever were 86.24 per cent of the total deaths. 55. The morbidity from typhoid fever per 1000 of mean strength was a httle less than one-fifth (192.65). 56. The mortahty from typhoid fever per 1000 of mean strength was 14.63. 57. The average period of incubation in typhoid fever is probably about ten and a half days. The following table contains data illustrating these points: 36o TYPHOID FEVER. ■sssea -sia HTB raoi; sqjBaa oj pioqdAx niojj 00 00 00 00 00 00 On O^ m M NO PI 00 00 p) •sasBa t^ g\ N onoo w OVO M in'O oo ro •* H (N H . O in ovd CMn O O 00 in PI t^ On o NO •ooo'ooi 13(1 ajB^ iljipiqjoji in 0\ "+00 t^ O N r^ m rOMO ro O -^J- On " M O M M c> H d^ in M CT H H H P) On O C>NO NO PI •ooo'ooi On t^ t^ O "^ in M cs H r^ r^ n PO O O fO M « M M M C^ NO o ■5j- in M M NO ■* •jaAa^ pioqd^x nioj} sqjBaa Tj- 1^ a\ M o oo Tj- M On M m ■Ti- ro ■* MM M o o NO PI o 00 in •3]qBqojd puB otBjJ33 'jaA9j[ pioqdix Jo S3SB3 H 00 00 NO O ro P) M On tc o M •sjnamiSa^ jo jaqnin^ PI r^ t^OO PI o^ PI M MP! in t^ 00 PI On 1 •a a o O First Army Corps (Chickamauga) Third Army Corps (Chickamauga) Fourth Army Corps (Tampa) . . Second Army Corps (Alger) . . . Second Army Corps (Meade) . . Seventh Army Corps, Second Divi- sion (Jacksonville) C o •55 V Q •H H uT Oh u o U >% S < > > 1— I X X "o > . c b' ^ ^ P^ .^ .- ^ (J • Jd •r-i rf "S i3 o- PQ C/J C/^ CAl COI tn IH 1-1 1-1 tH IH >-l IH l-l h il)(DH "rt t^ rt 3 XI 3 << ^O c bb G W CO •3 B o 2 "-^^^ 00 O • > D >^ c „ O rt c/3 (J H-l 1-1 370 TYPHOID FEVER. O CO O CO K t4_| t4-l o ^ u U5 ,Q w x> a; 3 o - o-a >^ ^ « W ^ • O ■* !^ b£ H § '^ ^ ^ 3 So . . "^ ^ H HWP-i W PL| -.^^ -f-» eg O tn ^^ o (D O) (U OJ OJ 77^ c3 c^ d cd d d O C o to ■* o o On O 00 00 On On H H CO c c c ^ c c h- ■» I-' IS S bc j3 h^ 21 is o ^ ~ 2 ^3rSbb-S,j5ffi^gy fo aJ U WK M P^ .'SPm Q^ ■V ■ • TD d ; C I .TJ =« <1> • s M c3 3 U nj CI, ►^ tn ^ • 5 ■& 1- Pi ^ §"£ xo Ph hS o I— I Ph O Ph O w p; < o o o o* o is ts u A 1 o u 1 •a ■^ O •* ro lO O^ On P) H H . . W VO 00 lO • ro . oo • ■ . . CO • • ■ p-g o o M \0 ■* O t^ On O N H t^ On IH NO CO C 8 ^1 O ^ On H vO 00 rC M -^ M M H 00 >0 H ^ "^nO Tt oi n CO t^NO t^ o H t^ CO M H 4 o a IH t^ _ lO t^ M OnOnoO 00 NO t^ lO CO rO ■ w O IN M M oj u-) 01 t^ rONO LO H 00 CO t^ t^ 0) ■ H NO M ■ 3 -^ p:5« a IH .NO NO Ti-NO On IH 2 OS 1- n N M 00 H On Tt- H t^OO 00 0< 01 H NO r^ t^oo ■ M lO H ■ M O M H NO H lO O r^NO t^ ■* O On M lO ■* O ro M 04 CS 4^ NO M O 0) w T|- 00 w 01 t^ NO CO lO On ■* 01 M H CO O o a M . . . fo • • M • ro ■ ■ ID ■ On lO ■ ■ ■ 0) oo ■ * ■ 00 . M CO • '00 ■ o M IN "* . . . 0) ro ■ ■ ■ NO ro ■ ■ ■ 00 00 . Ph 6 s H-^ .^ "^ 1 ^ . . . . (-1 ^— ' O tn ■ _ M o 2 o 5 CCS G-a c c c cxt; APPENDIX XVI. 373 0\ N IT) vo f^ CO lO • \0 . ■+ N . M H • W O H\0 On ■* On^ r^ lo t^ 00 CKVO 00 (N lO rooo t^oo lO . Tj- ro t^ fO 00 00 rj- H o 00 CO J^OO t^ P) NO 00 w 00 O P) 00 i^ PI M On t^ 00 nO 00 lOOO NO rONO M O On N 1/^ ro vo PO ■* ro -^ CO ^NO T^ o w H PO « On OnOO pi O PO M PI M O NO On pi PI PI PO M PI PI ON M On m ionO r^ CO 00 t^ lO Tj- ly-i ponO pi VO PI NO On M lO M oo O t- NO Tl- t^ coco M •>*00 oo ■* N 00 ■* 01 O !N OnnO lO m O lO pq M PI NO On NO PO r^ ir> PONO NO PI roNO M iri PI PI PI o T}- PI PO PI l^ O O On O PI O t^ m t^ m PO t^ t^ lOOO O r^ M PI On PI CO PI PI lO M NO Ti- PI PI U^ PI M NO M PO M NO PI On •^ ir> pOnO PO •^ lO u^no pi lOOO 00 Tt- PI tONO O 00 PI ON ONOO -^oo On q_ rO00__Nq^ NCrpoioO.ro M Tj* On t^ M lO On PI 00 VO lO Tj- t^ ro PO Th OnOO 00 PO PO PO i^ t^ O 00 00 -* lO lO Tj- NO M OnOO Tf M Tt oo" i-Too" r^ POOO PI PI t^NO PI PI M ■^ VONO f^ On t^nO no no _,. 00 PO lOCO nn ■* -^No^oo^^sg ri o" tooo" f;; MM ^•' lO t^ PI NO PO ^ -* ON On M M NO 00 On On .2 .^^>^ 4) .s .X . :5 u5 W ^ S^^u^ u a U ^ ^ CI d-g 3 M TI Tj +2 3 P a ■S ?3 3 o-S §0?:' p 3 oj ai rt ^ • M C P pH r- O nS ■g ti >, ^s TO c^ Cj ra flj cqpqmmm D (D - ro NO 00 r^oo O M -* H M M NO On ja ro On ro lO O O W n § .5 t^ lOOO •* O Tj- 1^ On NO O r^ to toNO 0) '^ ■^ ro O On^ W t^ to On . O 00 CO CO l-l H Tj- ^ w fO On CO .2 3 M e- ro lo t^ H O NO to r^NO NO 1^ t^ 04 to t^ NO ■* 01 o 3 O K NO rooo O Tl- 00 rONO ro c^^ NO t^ t^NO r^ On O (^ O On ro f) NO 00 OnnO toNO H 00 O lo l-l On O On O On On On no lo 00 c< w -^ lyr* lO M o W ■* M C< CS O H '^ 01 ■* r^ 'i- '^l- 01 ^ NO nO 00 o< 00 lo 01 On \0 CO O fO u-3 r^ t^ O 01 t^ w l/^ -I- COOO CO NO TfNO •+ ■* •* f-00 01 On On O ^ N PO •?t- ro O N t^ On •* On O. ^ lO CO M lO CO CO r^ O CO CO W Tf t^ CO M 01 to ■* 01 NO lO M U-500 !>. CO Tj- in O O >O00 lo M NO NO M X^ « cOnO t-- '^ r^O lO l>-00 ON O O O 00 !>. lO W lO •* lO H M On LO CO t~- OnOO 00 lO CO M ^ CO CO NO w H COOO 1-1 CO CI 11 lo m 01 01 00 rh 01 COnO O M H lO M 0< too to 00 On to fO 01 00 w On «>• CO CO •* On t^ •* O NO VO VO On l^ NO t^ O CO ^ 00 lO N lO On to CO P) M t^ 0) t~- ^nO O no CO M w w CO vo n On rj- Tj- 01 Ci Tj- l-l O CO t^ On CO NO 01 lO to NO NO r^NO NO t^ M 01 lO CO On to On lOOO W to M M 1>.n0 no t^ . 01 !M 00 t^ M 1>.nO m COMO On w 01 •* OnO O O CO . . OO . o to w NO On M . . '^ . t^ M NO • • ■ 00 •OO 1-1 O NO • On ■ ■ OO ■ t^ OO ■ • oq • • ■ 01 01 CO M ■ '^ • • M ■ Tj- 01 to CO „ to to r^oo -+ t^ -t CO t^ O to t^ CO t^ 01 t^r~. On On •* m CO O NO to c> O ^ CO On r-- f-NO ON to On 1-1 NO M On ■^ On CO M 01 OO NO M O 01 ZH.) M On T}- M 00 "* t-. CO CO CO to •* On On M t^ to H t^ to CO ^ COOO 01 O CO 1-1 to On On OnOO "+ O to CO O "i- tooo O t-~ to 00 M M 01 IH -* 01 H H ^ M CO On 01 to 01 M 1-1 NO H H NO l-l CO M 'i- M M CO 00 t^ O NO O O 01 M T)-00 f^ 01 •>:f OO ■* On ■* l>. to On NO t^ O '^t- 01 o NO NO 1-1 M CO NO CONO M CO CO ■* to CO to to O t^NO 1-1 l-l COOO t^ t^NO On or M tONO O O On to to 01 CO t^ 00 r^ 01 CO On NO to 1-1 1-1 NO Os H CO 00 oq 00 to On M On 01 NO 00 to to CO to 00 On 01 w t^ 01 to to 00 M 01 M 01 M M ^ M OOOO 01 oooo M to 1-1 rt to M OO CO " w 01 Ohio Mass. N. Y. -6 c 1— 1 Ohio N. H. N. Y. N. Y. Ky. c c O Mass. Iowa Ohio s Colo. Mich. N. H. d P^ a N. Y. Wis. N.J. Ind. N. Y. d > "5 § 6 g O O o .5 d £ "d'> O O O O O uuuuu 3 Ji c o 2 d d > >-^ o c^ c^ cj cj ^ PQQQQ O O O 3 3 OQQQQ 3 S::s:2.= -h7^ TYPHOID FEVER. o o o o o a> a .El o > 0) 13 1 1 o H M ^ to CO On O m H . H . . t^ . O ■ • tH • . 00 ■ ■ . . CO • ■ O O ■ O CO SO r^ • Tt to . • OS . . PO ui o O 00 oo O CO t^ w J^ O O P) l^ CO On to H to H M oo Tt M . M M On N OnO O CO H M M p) O PI 00 PI O M 00 CO PI CO M OS PI PI Tt 4 o \0 Tt H t^ On Tt P< PI ^ 1^ so On toOO OI Tt TtSO 00 w O O CO Tt to "t M W CO to OS O O 00 Tt PI PO M to O On SO SO PI to -^ to to H M SO o r^ t^ Ttoo H M 00 <3 r^ PI Tt l^so On OS P< SO cooo r-- t^ P) CO N M M Tt COOO OnOO CO O ro H POOO POOO PO PI Tt M SO so M PI H Tt o Ttoo On t-~ Tt H to co^O M O M >0 O Os CO W CO to t^ CS VO M 0) \0 -t CN M Tt PI On *^ to CO H Tt M CO CO t^sO OS Tt SO H PI H to f^ M H PI to o M t^ CO t^ On t^ vO O NO t^ to M to 0* cs M O w On . Tt P) NO NO ■ PO P) CO PO ■ OS o CO r^ to M PI ^ to Tt COOO to tooO M N Tt to OS to CO M CO o 1 N .00 .CO Tt ■ ci • Tt co ■ \0 ■ M • M • to ■ ■ CO ■ PO ■ ■ '. M Tt 00 PI . H to Tt • vd • d CO ■ O ■ M . t^ . CO . ■ P) ■ CO ■ • M ■ CO ■ ■ ■ Os PI 00 O 00 w CO . to . O CO ■ t^ " O . o . . . . . o ■ ■ PI ■ • CO c O & Pi HI " CO to 01 w PI 00 00 PO M ^ 1^ Tt M M t^ oo" H PO C?. to to M ^ w O CO w On toOO M PI p) r^ Tt MO 0_^ Pl^ On to r^ CO to On l-t M CO H Tt H SO to PI w o Tt On w SO to 00_^ 1 0, "^.^^.^ On CO pT pT Tt M M M M H 00 so tH r^ to O^ to t^ so'oo" t^ CS M Os s i CO On t^'O CO PO -i- O COM3 t^ lO cooo pT c? c> ^ Tt to lO P< O PO l-l CO to PI W PO O M o NO to W M CO tC H CO to hT M CO H ^ M SO O PO PO CO On J>- M CO M 1 ■^00, "t^^ On PI O O" pT M IH Ht M M OS to PI Tt-SO M CO to so''oo" »^ PI M 00 0) .2 CO Erie Escanaba .... Evansville .... Everett Fall River .... Findlay Fitchburg .... Flint Fort Wayne . . . Framingham (town) Frederick .... Fresno Gardner (town). . Geneva Glens Falls . . . Gloucester .... Gloversville . . . Grand Rapids . . APPENDIX XVI. 377 « r^* n ro fO f^ t^ fO ro >* M • . •* CJ O . . . ■ . u-j-C vO ... . X ■ • . (NO . . O Cn ■ O O OOO Tt ro O P< ri-X f) N lO O SO t>> CO Tf lo ro ^ M to to M o M r^ t^ O ■* VO w O i-i Tj- lo lo ■ ■ 00 11 CO CO ■ M Tj-X VO to ■* X 11 •* M O c- -* O lo to - ^^, . N C^ X -^X « X wv CO ■* M O CI to O I/-, o o 0\ ^ >- 1-1 CO •* t-l lO n O ■ t^O w O ■ CO CO to to " w T ■* PI O O P) o t 1>.X r^ O o^ to coo 11 CI -^J-O •* S" X -"l- t^ ■ VO CO t>- 11 LOX O Tf VO PI C\ 11 o PO CO 6 PI O w woo u^ CO lO 11 O n Tf rj- O to •* r^O ^ PI p) PI o lO H ' 0^ CO Pi H PI PI O X PI 11 PO PO _ t^ r^ to t>. ■ X O CO Tt- ' iri ro PI -* vo t>. r^ PO lO CO PI n lO VO CO PI CO <3 0^ • c~ PI Tt n X PO '* M PI CO . vC lO 6 to PI X to lO •+ " to ■ o -^ PI to x' CI •* '^ CO Tf PI >* o t~- to o cox Tf 'd- ^ O X ^ CO X tnO o ^ X lO C^ ^ lO ^^ -+ PI o PI o to to o CO v;j ^ 1-1 Cn PI to On n o> to '^ PI ^ X M u lOX X -' X LO '^ C' r<^ lO lO ^ ■* ^ o PI ■* to to PI O X ^c PI PO t^ u*'. •+ PI to t^ U-1 lO c^ O •* PI X PI o ^ -i- to loO V^ o PI PI PI h-l lO C-- CO vO •^ PI PI to PI to PI >+ PI •*o t^ o o yj-i o ■* w X „ rf -y PI X u-> loO o O^X PI ^ CO on 1^ r^ o U-, t^ covO M PI On '^O r^O <) lO PO 0<) PI t^ Hn t^ CO VO c> to " u-iX " PI PO r-- lo Tl- PI -1 PI X t^ PI 11 ■^ O X J>. -r X N PO PI o o ^ r^ rr o VO On On CO On o> n O to to lO X tr; PI o •O M PI lO J>. lO ■* n PI PI o PI o S ^uo^fS izuSfSz J3 O -!^ J3 iv^" ^ u •- _u u 1^ U J >'_■ ►5 2; ^"5 c P3 > o .- J^ ~ c y •2*3 p o ti-" :r o ■— ^ S S 5 f _ CCrSrtiS rtcjrirSO C S ■2 >^ ^ 000^J5 OOHSS S 23 E E E SEEE— J: ,^ i±; ^iS ii ; 1 "I I "i ci c3 cj «S o U 378 TYPHOID FEVER. >o in 00 NO vn t^ lO NO o in IT) PO . 00 ■ • • . VO OOO H lO ■ CO lO to (N ■ 00 CO "It CO J^ o m CO O ro l^ O t^ re re lo It N \o \o ^ • o .... 00 \0 lO ■ NO . f 1 N . re • 1- . re • . O\00 >0 t^ •* 1-1 uo re u^ •* 0) 00 •* o re 1-1 00 re loO M M re i-i re re On r^ r^ t^NO re -^ re -* re 1-1 ■ re^O On • re ^ O OO O rj- CNSO Cs o Cn ON re o 00 ■* re looo C) re M O N t-" O w M O '^ M re re ■ D re 1-1 reO O NO loco lO « 0) H M \0 lo re '^ x^ lo c^ NO i-t re 1-1 l^ O 1-t M f^NO t^ NO t~ t^OO t^ OS t^ o M re H LO M O 1>- IM lO LO t^ re reoo t~- C^l « O PI •+ vo vo to ro t^ H CO • -+ On M M oo NO CO ■ -1- MO) " t^ M re t^OO NO lO . 1-1 NO re -* M rl-CO re NO 00 re On lO in re (s M w CO re lO veco N On P) re On ^ HI M On On 1-1 00 t^ t^NO re !>. un M vo ve t^ On lo O w re (N NO ve O O NO M ID O re 01 _ M t^ lO 0) r}- . NO O OO ■^ 01 00 lO CI reoo NO O CO 00 •* •* C) t^ tJ- I-i LO r^ On H 00 ;• t^ OOO^ re M oT o" lo NO M M M M r^NO re r- On lO VO t^ I-I NO re 0_ 0.^00 CO lo re -t d" 0? M 01 M M I-I tTnO to lO le OO OO On oOnO Nq_NO^ 01_ 0) NO " C?. ■* H o" M M IH 01 HI re re 0" re M tJ. M On l-t 00 O reNO On lo 01 r^ Cnco no" no" ^ ■^oo" M M On 1-1 01 re t- -+ •+ •* 1-1 0) O O NO lO 0) H IOnO Oo" ^ On re re NO re 1-1 1-1 re t^ w NO OOO CO O CO On ^ On NO f;^ le re no" o" m o" re lO M M M 1-1 le t^ Cnco -t Cn re O lO ^ " reNO_ q^ On no" t^ re d" i-T M 1-1 M M HI HI ■* 01 O CO On -*nO 01 HI oi_ 01 On reoo d'oo" oT oT oT HI Ht M O HI Hf NO On 01 01 N. Y. Ind. Ky. Mass. Va. w u5 wi ,/ tn . • o t:^ ijj .^ • . [S-c o "5 tn C J3 . 52 ^ C u c a u 0) o ?^-^ 3 H^r.'i^ ^ ^ > O M •*-' ' y ^ ^ --".T-l ^^. S;=5^ ^S.S^^ ll.^i^tJ co^^:^ ^.£"6^^ ■S_^ -oogc ^^S^i ocoa:^ •■ggsi.cp ^S.i-'g c.5i;^§-§ ly-^-^-H .S.2£§-^ -5:5 8 §-3 ,-, hn^ Se pHS^O-GJi cecEfc- ut-i-i-u-. cS-C—GC orPSoS. F-j:Srtcd rtrtrtcS:^ rtnjcirart SjUOoo 3j^^.^ J^S^S ^S^^S ^^^^^ ^SSSS 38o TYPHOID FEVER. o o o o o is p. "S u i is > 1 o r^ M in On 00 rh Tj- 10 • ■ • rc N • • ■ . P) m • . PO ro PO ■ NO • ■ ro • in • . ro • in o "^ <^ . . . 1000 ■ ■ ■ ro ro ■ ■ ■ 00 t^ ■* t^ fO NO PI TtNO 00 M P) PI l-l M NO _ M r^ d ■ ^NO On On ■ P< t^ m J>.NO PI 00 t>. i-i PI t^ 4 o >0 >rioO ■* ■* 00 NO "^j- On w t^NO 00 PI 00 t^ ■* On r^NO 1000 10 H in PO t^ •* p) M Tj- in -^ NO NO Tf PO M PI NO 00 ON Tj- pi M m o rj- t^vO vo M 00 H NO in . PO Tj- in PI 00 i^ 00 On M N 00 NO H M M inNO w M On t^ • '^l-NO 00 M H 00 On in On H w NO o H On -"l-OO NO M H On H Tj- ■* 00 m -* Tf M rt M CO VO l^ in inNO PO Tj- H P< 00 W .»t 1^00 m M PO On 'i- Tt PI M M M m H O M t^ 10 10 l^ t^ H t^ OnOO . t-Tl- PI PI fC C< O>00 M Tj- po ro t~~ PI 00 00 PC M p) inNO M in ■ fONO in PO ■ MOO PO OnOO PO M Tj- d t^NO NO ■ 00 !>. ■ p< rONO ■ • "00 d a 00 inoo r-~ : NO 4 tj- ■ M CO in • -NO 00 a 00 16. I 42.4 59-9 P» • • PI a 3 1905 u. s. Census Estimate. »0 M NO 10 00 00 0> C< 00 NO W NO W NCT 10 O^0<^ pT rj-oo Tj- Ti- 00 .^ t^NO t^ 00 On On M m h" pT h" pTncT H H NO Tl- H CO P) NO ^ M t^ Tj- Tl- PO 00 M nO__ On PO 0_ pT in .^no" in M H PI PI M t^ PO r>- M On PI On M PI o'no" -4 PI PI 00 i i Oi c M M 10 On NO 10 « H 00 r^ 00 10 M 10 m ^ T? C> O^ M po moo On P) 00 H M NO NO in PO t^ ^ On cT in pT 00" ro M 00 PO W P) PI t^ OnOO pi PO NO t^ PI .* t^ PI H PI On H PO M 0" -* M H PI PI H 20,818 23,898 80,865 4) Ind. N. Y. Ohio Conn. Mass. N.J. Wis. Minn. Ala. N.J. N.J. Pa. N. Y. Ind. Iowa Mich. N. H. Tenn. b Michigan City Middletown . Middletown . Middletown . Milford (town) MiUville . . Milwaukee . Minneapolis Mobile . . Montclair . Momstown Mt. Carmel Mt. Vernon Muncie . . Muscatine . Muskegon . Nashua . . Nashville . APPENDIX XVI. 381 - PO O • • P*^ • C^ • 10 VOO i^Tj'i-PC t^C"'"^ PlO^' -t^ .POl-*- .UO-P*. )-(MMMMI-l WCS'IO POLO.-^ _OC-. "PC vCCCC^OvO OTl-POt^t^w M t^oO PC X PC O 00 o • t>. t^oc 00 t1-piOp)0. Orfiipir^vc tJ-tj-^i-i Opc-*Om O HI PC^PCPC--* wwNwww WLO-^O iriPOPl'-tCO ■^ PC .^.X O i/", Tj- p) r^o OC O ■* -^^C Cs <3 >-i n xn r^t^po pccC O O -^ O P! U-. t^ LoO iJO vOpjpjpcOO PCQPiO ■* PCO 00 O MWHiPiPi re PI PC" MHHP^MMP^ f-iwrj-pi \Opc-h pc vnoPCPC-* -CCOC" "CC-^omoc ov C^oo r>- r-» r^ r^ Tj- o, OOr^OCN -tOOOp) t^-^Ov 'LnO o « vooo pc pi O O 00 ^ IM.-ICOIO'-I PC-^'^Pl l-ll-(MtHMl-l CSWPCHi pspc*-t w OPCMt^-PC .HwMpqu-) PCt^PCiOi-i"* vOiOMM u-,OC 00 t^ ■* MVSC-. l/^PC '^OOC'^PC OlO'TOOw'* or^ t^oc pi pc o ijo O ■^PlPiPCi-' i-HPCPC'^Pl P)>hPji-iP ' ■ u-i ■ ** ■ O 00 00 u-.oC O O ■ ■ ■ • ■ ■ n ■ ■p)' 'Pf'ly-l' M MMMPC Pi"'' '''m' PC .'"'.". *^ u->- O ^^ . . . . . . CN . ■ " 'r^' 'C— " OPC^O-—P) O''' '"'O" ■ PI ' ' p^ ■ O ' PI M PI M M PI M ■ ■ • * ' ' w * C^ w 00 P) PI PI r^O^ PC00__ pT cf '^ p" w P) t~~ PC PC r^ PC 1^ PC PI ^ PCX M TJ-NC PC PC c> c? d^ 0" p< - M P» PC Pi X X 0~ Pi PC PC -T Ln f^ c;x_ On m" iP, pT tC (-r r~- U-. c~ t^ 0__ Pi PC -^ M r? M pp 0^ Pi X iJ-> X w t^ Pi M PCO PC o^o ^ X Pi P< W Pi 0\ M O- t^ Pi Pi 0- PC Pi PC ^ On 0__X__ -^ to (> icO"o" PC P< PI PC PI w" 00 1-00 PI X X -* PI ^ ON ^ ^nO^ •* Os d> pT iri M N Pi 20,006 108,027 17.54''^ 287,104 14,720 Pi t^ Pi r^. c> M OX C- Pi Pl_ u-. LT-. 0^ On t^ CT Pi" ti PC U", ir-,vC •* Pi M X__ M PC M ^ t^ PCX r-- ir; Tj- t^ 0__ M o ^ o'x" ■^ T? •:1- r-i Pi w Ci C^ M Tj- t^ r^ PC PCX u-> PC PC 0_ irj rt X" X~ pT PC C> Pi « Pi PC M p< Mass. Conn. Ind. Mass. Conn. • C ci • d>N^|^ > ! c o '^a rto N fO '^ o ^ fO 0\ H M ^ M NO r^ CO VONO o o t^ ■* »0 Tt- t^ ro O o J:^ 0\ On O NO t^ CO VO t- ^ w (N Tj-vO (N NO CJ H o " fO (N o CO ro O fO N vr> lr> t^ P) O On M N is (N \o O •* li^ M ^ O M On ONVO PJ ^ N On • n H o OO t>- ^ 0) ON -+ Thoo 2 n w ^ m lO M 0) ON "* M ^ M ^ ^ ON CO PI fit M H O N VO w t^ ■* •* VO Ol >-> CO t-. M r^ VO VO . M M M -+ N i_i o O Tl- O NO On (N vonO CO M ■ M r^ M > (N - 00 On On Tj- t^ VO w NO ^ t^ rt J3 J3 o o ^pis § C! g ^ g g nj ■g^wil- .t! -^w -y^a-rtj c!2<^'" t^59=^o oox) .g^ig-g ^£c-^y> gg^y^ ^3° O O O O O a bcJi a u titip^aj rtcSS iz; iz; :z; iz; :z; OOOOO OOOpl,pm PhPuPl, APPENDIX XVI. 383 N 00 ro 10 00 00 Os t- •* M »0 M CO . . t-. r^ rl- . . H ro t^ . H . . . ^ . H . M CO . ro M . • t^ t^OO 01 ■ « 10 M "* ro On CO fO • Tt- H H CO • 0 H NO CO CO I NO t^ O NO O H 0) r^ Tj- cq M 0) ^ t^ 0) NO On On O^ M N 00 ir> M !>. TtMO CO to ^ lONO 00 00 M 00 10 00 COOO •* On i-t M ON ■^ Tj- CO 0) VO t~» O H NO ■* o r^oo H -* . . . . . . . .. 0< • oq ■ CO ■ LO t^ W H M 00 -St On c^-jNO LO ^ oq H 10 NO LO t^ 01 NO 00 ON ■* l-l vonO no M NO T)- On CO ^ ^ ■* ■^ CO LO 00 r^ (N 00 COOO CO H -rt-oa H H 01 NO CO H CO 10 H M CO ■* 1000 10 w M On -* 't M CONO LOCO 00 00 Tl- M NO CI H W WHO) LO M 0< H W On CO CO M H CO M 00 On CO t^ M NO NO On On 01 OnOO 10 LO NO t^ NO On t^ x^ 0) On 00 10 On NO M LO M NO NO -* OnnO loco t1- CO t~- 0\ M 't COMD -^CO MD t^ COnO 10 r-- H CO M ^NO 00 NO t^ vn t>-00 H H H 10 CO ON On On On t^ CO 10 r:t- LOOO NO CO CO M M rq M H 1-1 CO M LO On M M M W M r^ oi CO 0) H H tn 43 ji! k! bbhj o U ^^^S>Ph ^HhS^Pm gg^^S O^Of^P. ^p^usS ^ in en ^ g tJ ti '(d >-> PL| PL^ Ph PMPh O .2 hM I — 1 uj F C li "C tn .rp O O O o Ph PliPhPM Ph .^ ^ y) yi en )H t-i 1-. ti ti 00000 -^4^ o ^ ^ -2 bO'S -O 3 P Ji' pLK PM PL, Ph pl^ PhPhPhO'O' Pi 384 TYPHOID FEVER. O Ph >^ H Q < "^ O I— I h <; h-i Ph O Ph o w < o o o o* o & £ J] i w O Ov ID VO IN Tj- On CO H o t^ 0\ • lo f^ - r^ ... 00 H . . . ^ . H 00 HI • • HI H (N ■ t^OO • NO P) • in o Ov 00 00 H Ov N in m -^ t^oo CS 00 NO t^NO oo N On U-) IT) in Tj- M MM Tf M M N o fO w M H -^ C^NO lO t^ P) O NO CN) M HI N HI -d- ii-> 4 o Oi ro 0 t^ On .NO CO d o Ov "^ . . '^ . On • ■ 00 ■ Tl- ■ • 00 • °o : : : : lO t^ C< HI to VONO On M On CO M M HI N On NO On ■ CN 00 d. Ov 00 . . lo . CO ■ " ro ■ ro " ■ ^ ■ 00 • ■ ■ ■ O O 00 CO lO NO ^ f) 00 On CS CO CS M HI NO (S d CO ; Ov 00 M 4 • • •* • NO ■ ■ fO ■ ID ... . M NO VO coco Tt HI NO NO t^ HI HI HI 01 CN| o . CO • • a 1 igos U.S. Census Estimate. M OnnO O m M li-) rooo O On fT OvNd~ On 00 H M 00 C^ O On •* M M lO ^ VO lO HI s Pa. Mass. Ind. Va. N. H. N. Y. Me. N. Y. Vt. Cal. Mich. Mo. Mo. Minn. Mass. Utah Tex. Cal. i b . . . Salt Lake City San Antonio . San Diego . . Reading . . Revere (town^ Richmond . Richmond . Rochester . Rochester . Rockland . Rome . . . Rutland . . Sacramento Saginaw . . St. Joseph . St. Louis . St. Paul . . Salem . . . APPENDIX XVI. 385 CM» lf> !>. Cv ir-. N M t^ r^ X M L/- !>-. •* fS rO n ^ r^ tr to ^ « r^ =^ w t-i tn •* c> ■LT c M « « ■^ K >o T - f. tT t « « >-l t^ c< >^ 1-. ro M X ■x: vC t^ vC •* ro t~. ro ^ ^ ^ t^ ~, _ n r-. fo ^ 00 X, tr « *"* f^ "^ "3- "^ rO c< «-( N in DC fO C) f) to '^ cs ■* ■* •*CC Ti-X t-~ \j~,zc t^ X ■LT, tr> ^ c- to X M 00 to -, ro N M t-1 vO Pi cr. M vC t^ j:^ vC X n ir-. — , -J r*^ ro 00 _ >o „ ^ r-. fT) N ■^ 10 x^ fl ~ c^ " " - -& 00 '^ *"• fl to r^ m 1-) to rn - - - u-. -, - LT, C - -- -+ Ci I^ Pi to « t^ 10, vC - •i- M to 10 „ r^ XT; — _ X ^ y. ^ — u~ ^ X ^ rO 1- •* C t-~ j-^ ^ r- i^ M f^ T ~ U-, ro ~ ""- ~ ~ "" X ^ M 10 CC -* ■<*■ ^ to •"* to M N ^nt^o .^ „ ■0 coo r^ f^ X « li^ t^O M M ^ 00 (N t~- O-* fO M ■* M "* t^ 00 t~. r^ t^ >-t „ f^ 00 to (S ^00 1- « N t^'^ HH fl M M VO 10 •* CO t^ tn f<^ cs "* tH (*■ W f) I-! t^oo o> t>- ri-OO '^ ri- c- X t^ ro r>. H M N l^j f^ _ N X Tt- n '^ r^ ^ -V -^ _ un X xo r-i -V O- r> !^ to Cv IS M "^ i>. - cs ^^ (-C r^ ^ ■" t>4 ^ " LTV '' M "■ "■ TJ- •^ cs CN r^ fO C O -^X rOO to O f^ ^ O r~-X T fO r- f*^0C oc O ^ IN O O fO T? ro ^r "^ tC -C ej M -1- — O fO "± Xtor^ O-O-fO to C Pi r^ O PO M ;? d^ c fo -f —^ tooc" o 0^0 - Tj- o fi CJ to to ■^ O Pi to C- IN f^ P^ C Ci O O O to - o cr c o N n ^ X Tr M !_, HH PC ^ „ tOCC ^ ^ J^. ^ X „ _^ _t PC r^ Pi 00 m tT 00 IN f^ i~( -^ ^ -T- -7- to to '■> -r r^ '^ t^ ^ r^ t--X p< t^ to T to • 00 ro PI lO O r- t^NO «^ o o M NO O lo O On no t>. rOGO d M On On O fO 1~- NO 00 1^ On w -+ O H to CO m (U OT 00 lo O w Lo lO OnOO t^ O NO NO M M O M M 00 t^ t-* r^oo uo roco ■Tt- H lO O) NO NO fO M t^ Ol H f) ■* rONO H OO ONOO On CNl CNl looo t^ cTno'oo" oT On HO) O O r^ r^ H r^ NO O O vooo ro ■^ rONO H ro ro ONOO O 00 CO Tl- M On CO "* O NO (M t^ H rooO M rooo NO H lo r^ Ti- CNl r^ uo NO 00 O 00 On no coco 00 00 On NO NO vo On O 00 NO t^ col—"' uS^g^ C > c >^ o (J nj D O 'S O ;-i iH ^ C ^ 5 QJ Cti CL) t3 ■ c fl d o ^55 f „ S 2 Ml tio w)3i:, d d S .— >H o) tn c^ c^ cd cd cd 3 ^ ^ IH »H IH O t^ 00" •^cc'^c" O C3 y; . w Iu5 u ^"3. > "«^ t-l ~ '^ CJ ij y y ^^^^ O 1^ .;; o — ..s 5 ^ H ^ =33 = 5 -I 10 O ■^ •* ■* w 1-1 10 O w l^) O P< POCC >-i t^ PI P) ■* C-00 O C> -^06 cc rC -^ i-i 1-1 M p) 1-1 Tj- ■^ 6 i § pi ^ ^ o 00' P) d 10 r>. PD r^oo 10 PO 00 COOO Cn 00 00 l/l t^ PI Tt 10 t>- Cn ; POCC to On M CO •* t- ^CO t^ lA iv^ C^ PO ro PO NO f^ 00 PI PO On •* ^0 C^m 0. -T PI 11 ; PO vn •* MOO r-- M PO •* m •* PO PI PI t^ h. POO X 00 10 M in ■ P! ^ -i- r^^ :> ■* - -. PO „ CO )1 tn CO P) PJ ^ p) ■o in ^0 r/1 M 30 10 t-~o in trs <-> PO M ^ ■* ■ in w in 00 ^ PO •^ *H ■* in Tf ' ro M M >H ;-> PO Mt n •^ PI -r. >_, >H M t-i •* PO P) X PI PI ro PI >o in ^ ^^^^^: ^^^^^ ;^>^ I \o fo fi c~ ox o -* o o t^ ■* ^ ; p ^ J £ n c G- c 3 c3 3 3 ci O I-I H t^ O X 3 ^ "5 •:2 T' 388 TYPHOID 'FEVER. TABLE II. — BOSTON, MASS., TABLE OF STATISTICS OF TYPHOID FEVER FROM 1810-1906. (Illustrating Chronological Distribution.) Population. Typhoid Fever. Typhus Fever. Year. Rate per Rate per Deaths. 100,000. Deaths. 100,000. 1810 33.787 1811 34,738 '63 181 5 1812 35,689 23 64 4 1813 36,640 42 124 5 1814 37,591 80 202 8 1815 38,542 r 51 132 5 1816 39.493 23 58 3 1817 40,444 59 146 2 1818 41,395 119 287 '1819 42,346 112 265 1820 43,298 51 117 8 1821 45,107 45 99 8 1822 46,916 34 72 4 1823 48,725 43 88 3 1824 50,534 62 122 8 1825 52,343 54 103 2 1826 54,152 50 92 4 1827 55,961 46 80 8 1828 57,770 . 46 79 9 1829 59,579 45 75 6 1830 61,392 iZ 53 7 1831 63,684 43 67 9 1832 65,976 60 91 I 1833 68,268 73 ■ 106 8 1834 70,560 70 98 4 1835 72,852 lOI 138 6 1836 75,144 68 90 5 1837 77,436 93 120 3 1838 79,728 42 42 7 1839 82,020 60 73 2 1840 84,311 69 81 8 1841 89,614 45 50 2 1842 95,251 65 68 2 1843 101,242 72 71 I 1844 107,610 73 67.8 APPENDIX XVI. 389 TABLE II. — TABLE OF STATISTICS OF TYPHOID FEVER. — Continued. Typhoid Fever. Typhus Fever. Years. Population. D« ^, Rate per ;aths. Deaths. Rate per 100,000. 100,000. 184s 114,366 97 84.8 1846 118,551 133 112 2 1847 122,890 166 541 9 1848 127,387 258 202 5 1849 132,048 119 90 I 1850 136,881 61 44 6 1851 141,308 88 62 2 1852, 145,878 46 31 5 1853 150,595 44 29 2 1854 155,464 38 24 4 1855 160,494 12 7 5 1856 163,820 70 42.7 6 3 7 1857 167,218 S3 49 .6 3 I 8 1858 170,685 73 42 ■9 2 I I 1859 174,227 74 42 . :; i860 177,840 I 10 61 .8 1861 180,646 96 53 .1 1862 183,497 85 46 •3 1863 186,390 I 30 69 •7 1864 189,331 I 07 56 ■5 10 5 3 1865 192,318 I 25 65 .0 12 6 2 1866 194,506 93 47 .8 8 4 I 1867 227,523 86 il .8 3 I 3 1868 231,024 I 20 51 •9 I 4 1869 246,541 I 38 56 .0 1870 250,526 I 68 67 . I 1871 258,032 I 76 68 .2 1872 265,764 2 29 86 .2 1873 321,200 2 43 75 .6 1874 331,395 2 02 61 .0 1875 341,919 7 27 66 ■4 1876 346,004 I 45 41 ■9 1877 350,138 I 56 44 .6 2 6 1878 354,322 I 20 zz •9 1879 358,554 I 19 3i .2 I 3 1880 362,839 I 54 42 ■4 1881 368,190 2 07 56 .2 1882 373,620 2 12 56.7 390 TYPHOID FEVER. TABLE II. — TABLE OF STATISTICS OF TYPHOID FEVER. — Continued. Population. Typhoid Fever. Typhus Fever. Years. Rate per Rate per Deaths. 100,000. Deaths. 100,000. 1883 379.129 198 52.2 ■ 2 0-5 1884 384,720 216 56 I I 3 1885 390.393 152 38 9 1886 401,374 135 iZ 6 1887 412,663 183 44 3 1888 424,274 170 40 I I 2 1889 436,208 186 42 6 1890 448,477 155 34 6 1891 457.772 154 33 6 1892 467,260 137 29 3 1893 476,945 148 31 1894 486,830 141 29 •1895 501,083 163 32 5 1896 516,305 162 31 4 1897 528,912 173 32 7 1898 541,827 185 34 1899 555.057 165 29 7 1900 560,892 143 25 5 1901 567,617 142 25 1902 574,465 139 24 2 1903 581,357 119 20 5 1004 588,320 135 22 9 1905 595.380 117 19 6 1906 602,440 122 20 3 The data for the years before 1845 are taken from the Census of Boston for 1845 by Lemuel Shattuck, Boston, 1846, and are " an abstract from the Printed Bills of Mortality." Subsequent data are taken from the last annual report of the Boston Board of Health. In the early records "typhus fever" and "typhoid fever" Mrere con- founded. The records also contain references to "fever," to "intermit- tent fever," " remittent fever," etc., many of which were doubtless typhoid fever, and which, if included, would make the figures from 25 to 50% more than those given in the table under " typhus fever." APPENDIX XVI. 391 •nopExndo J jo 0001 J8d sasnBO ^B raOJJ S8JBJ U-) 10 r^ 1000 w lomtN t^HOOoO^J w r
    . O O 0\ 10 r^ t^ H 00 lOVO (N CS M cofOfOO t^liOOONW 00 NO r>. M M M ? ■ •UOpBX -ndo'jjjo OOO'OOI JSd \0 ^00 Ht-~iorO'*'*cOcooo-*'^0<3^ ■<3-t>-M ■* PO ro Tt- ^ « H H On fOO H fOOvtot^i-i CN m rrM m Onioio^no^o Onw t^t^NOcxj^O Ttr^u-u-)'* r^ po PI PO PO •* ■ijilB^aoM Tb')ox jo -»d rl-HtoO M Oiorot^M -^ rooo nO OnmoO^OvO CnOO"* rOM PI PI rorOPO'^'^POPOPOP) popivom Mpq m M M P) a 4-* s •0 'o ja 0. ? 1 •IBjox P) GnmnO t|-iOOnP) POlOO POOO ^ •* PI K t^OO 00 •* 10 ■* t^CO ^OvOnOO OOOnO PI t^HO^O MHMPlMPlMPlPJly-jPlPJPlM On NO 00 ID •^ M M pq •jaq t^ PI l^ rO Cn^ id t^ "* PO On OnOO r^ po r^ m t^ ' HHP) MM MirjPOMPjH ; CO o\ M M •jaq -xn3A0>i POM POPOt^ioO ■T^NO00NO H On ir^ lO OCO 10 1^ ■ M H-HMPlMPlPlPiPOt^'^POP^M; ID r^ PI M M •jaqopo M M mmpipjpopjpOpO^mOiopO-*; 10 r^ PI M r-00 •3unf P) ■* P) " '^ pOnO t^ pO 1000 PI ■ PO «^ rj- " ; M MM M M 1 M M [ M •Abk oonotj- ;o\^NOo\ONP^ioiopiooooNPivroN ! irjNO w M •ipdv ■*nO P) no no r<^ t^ OnnO On IT) t^ t^OO On P) m H O • M M M M M M . M On r^ •qojBH "* -^oo pciop) P) ^Tj-ONiOM r^NO 00 ponO m • MPIM M M M MM. M ON M M M ■jIiBnjqgj PO 10 M PI -^ ID Tj-,z/0 00 P) t^ t^oo t^ M 00 w 00 • PO M M M MM. On PO M M •AjBnuBf M r^ PJ PO lONO Tj- -^ PO M M ^nO no 00 On t^ CJ m • MPIMPIMM MMMM- t^NO PI M sreai t^oO On M PI PO ■* u-)nO t^cO On M p) PO •* ionO 1^00 On m ii-5 lONO nonOnOnOnOnOnOnOnO t^t^t^t^l>.r^t^t^t^t^ oooooooococooooooooooooooooooooooooooooooococo 392 TYPHOID FEVER. •uoijEjndo J JO oooi Md sasnB;; IIB raojj sajBJ -qjBad jBnuuv Oni-i O 0 lo H ^ • fO 0) t^OO O MD ro On OnOO On O OnOO On ^ m h 00 t^NO ^■^lO^fO^iorOfO'* rONO CO ro CNi w "^ ro ^00 ■^Tt-rO'^^f^iOfO'^rororOrCfOPO •J3q -nioAOM ^ rooo lO-^ONtNOO Goo r-.0 t^ roco O O ^nO roON-^oiNO (m m on w r^rO'^PO<^iorO ^nO no vonO ^ pOnO nO '^lO'^POiOt^iOfOol PO •jgqopo w rONO w On roNO QNOOOiNwnwoOGONWoj -*oO cq oo lo ro ro t^ CO 0< NO' 'j- <~0 rONO ^ 'i-NO t^ r^ OnOO nO OnOO nOnO ^pDO t^-^rO'^PO WWW •jaq -rnajdgg NO >* On -^nO w ■* w O r^ moo 00 NO w no r^OO lOCO Tl- Tf LO M NO O) On N On LO ■* rO OnlO -^NO J>. On On pOOO t^ r^oO -^^fNO LO ro r-NO 00 ro ro ^ •}sn3nv M (73 IN O 00 t^ r^OO O ^ LO Ol On NO CN On^OI lo(N -^rOPOON-^ONON (N ON LO LO -^NO LO •* lonO w 00 r^ r^ LO lonO ■+ 'd-NO roM On lo ro ro M www w ■Mn[ w conO ro cs On NO lo *POCOPO(NC>D O w LOPOPOLOn LO-^Ol lO-^CN W 01 01 01 01 •aunf O TtNO r^ ro ot O r^jNO CO r^t-~»oO woo -^oO looo r^ On N w cO tJ- On woiwwojoOPOwwwQnO lo>0 oOw-^oirOWW 0104WNCJ w w 00 OnNO oo OnOO I^oO^CnNO 0100 NO w Q w CO t^ LO On "* ■* nO ^nO On oioiwwcorooiwwoOOt^LooDoOoOwNO(Nwwoioioiwoi •ipdy w lonO OO w lo lo On Ol LONO NOOO O O roCN-^oOrOONO poloOn'* wwwwww-^rOwWTtoOLOLOoorOrOwONOjololwrooOwro ■^OJVM 00 roini^oor^Low OnlooOwno h j^no loh woo t^LoO On^'^oO woiwwwro'd- wOi^t^'^^McsNO'^-vi-woiwoq^rooioi •AjBiijqaj O LO On oonO ^ro-+0 wnO wr^QNO w On NO oq -^-^nO ^-lopOiOOn wwoowoiwoioioioi OONO 00 oooi 0100 ^oooi w w wLorOw w •^JBnoBf t^ ro 01 01 0) oo On NO wQoor^wwNOG t^oO On ^ oonO w r^ Q On r^ wNOoiTfoowdOioo LONO w Tl- \t- r<700 oooi^oioioiONrDoioi •s •resA O w 01 CO 'sf LONO t^OO On O w 01 OO '^ LONO t^OO On O w 01 OO ■^ LONO OOOOOOOOOOOOOOOOOOOO OnOnOnOnOnOnOnOnOnOnO O G O O O O OOOOOCOOOOOOOOCOOOOOOOOOOOOOCOOOOOCOOOOO OnCnOnOnOnOnOn APPENDIX XVI. 393 TABLE IV. — TYPHOID FEVER DEATH-RATES IN CERTAIN CANADIAN CITIES PER 100,000. (Compiled for the Author by R. S. Lea, Consulting Engineer, Montreal.) 1 a 13 bi i 1 6 •g 3 St. Loui Sherbroo i a 1 •a a 1-^ 1 1 12 a t-l m a 1880 44-3 48.5 35-6 1881 10.9 66.1 64.0 20. 2 42.6 1882 73-0 70.6 47.2 112. 49-7 1883 84.0 80.9 30.5 52.3 33-1 1884 51-8 63.0 38.2 62. 1 39-2 33 8 1885 12.2 58.6 20.0 26.6 26.5 41 2 1886 34-5 45-7 26.4 53-7 12.6 47 8 1887 105.0 61. 1 46.2 22.3 37-0 63 9 1888 37-5 51.8 30-9 29.8 24.7 76 5 1889 41. 1 40.5 36.0 II-3 63-5 97 1890 40-3 93-5 28.6 26. 1 60.2 63 1891 30-9 93-9 24-5 38.8 67.3 94 2 1892 24.6 42.0 28.2 43-3 71.9 7 8 1893 37-6 39-5 10. 27-5 25-4 38 5 1894 39-S 23-4 17.8 21.2 20.2 68 4 '8.6 1895 47.8 28.9 23-5 37-1 79-4 120 1896 21-5 20.5 ... 62 . 9 34-5 24-5 27.2 21.5 59-0 7-9 1897 31-9 22. I ... 71. I 51.2 18.2 9.6 24-3 24.5 66 5 12.9 1898 25-3 II .0 •■• 43- 8 42.3 16.0 13-3 36.0 53-1 65 9 48.3 1899 20. 6 14-3 ... 17. 52.1 20.3 31-9 14.9 14.4 137 29.8 1900 46.7 7-3 16. 8 38.4 20.1 30-4 26.3 22.3 78 164.5 1901 50.2 I3-I 18.2 34. 21.7 17.8 19.0 15.8 39-0 36 I 125.2 1902 34-0 10. 1 17.4 16. 7 31-3 14-3 18.8 5-5 35 8 95-2 1903 42.6 12.7 7.1 49- 4 9-5 18.2 7.6 7.8 99-5 36 109.3 1904 50-5 9.8 50-7 31- 3 19-8 25.8 16.8 42.5 22. 1 5° 248.5 1905 22.4 II .2 JO. 6 31. 9 20.7 18.7 23-9 24.6 38.5 10 8 222.8 1906 48.7 8.3 56.4 33- S 33-6 31-4 34-8 36.2 38.4 52 8 152.2 1907 50.0 Population Estimates for igo6. Montreal 312,923 Toronto . . . . - . 222,903 Winnipeg 101,000 Ottawa 74>342 Quebec 72,034 Hamilton $4,562 London ...... 41,397 St. Louis 19,660 Brantford 18,973 Kingston 18,218 Sherbrooke 12,759 394 TYPHOID FEVER. Pi O I— I > Q < < ^ o p o to U I— I - I— I < > Q I— I O Ph >^ 1 d 5 K 2 ^ § *? " OOvlOOO OiM Tj-t^Tj- C^COOMOOC^'tCOMCOtO o. rj- t n n 46 « cod 6 corj Oivooooo loinioioo rrod Tf CO CO CO 4 O o 5 (3* t^t^i/ivO loo r--cor^ loo loTto o-^co\o r^vo W 00 O CO c r^t^oc ino^ooooo o o r^oo m o f^oo t^oo c>o for^ loo O 00 0) M M MM M MM MM M > O 00 0\(N CNOvO HVO -^O COM t^TfC00\lOT}-C^\0 ^ t^ CM _o M M\o -^oo^co cocor^ COCOCOCO^O C-) « OvCO^O O' o x^ O CO ° ". ot^oooo O COOO-^M looovOr^vOM CI MO oo M oo « dd'dcSdd'd'McT odo loioioo M o coo M o ^ tC rC 3 « ■* Tf lO lOVO 00 0> O M N I^O coo OCS lOOvCM >00 CM ^ o o t^ J^ t^t^t^t^t^t^oOOOCO co^'^'t'tioioioOOO r^ r^ J^ 00 hT m M M P< i iS in 6 o o o" o 00 tn O>0 f) COCO^OOO M ■^CO-^Nt^t^O COMOOI^ t^ w r^ CO 2 » -a 6 OOO C> vo CO CO c^ O^ CN dod d.4io4-ct44io4 c^ CO CO lo « f m t^MMMMMMM ^ wi XI _g r^ N r^o) co-^M cooo O CO o r^M oioo MOO -^ooo N CO lO 0^ ION ^MCO OnCO Ov^^ covO^ OvCO t^t^J^OOO lO o t- COtNCSWMMMCNM te n a o o* lovor^o M CNM M rj- r^iooo uo'J-coioTfcN coo O lo lO lO ^ n OMr->oco>oio(NCN MMCOCOOMCOIOIOOO lO t^ lO 00 S r-- in c^r^vOsOOc^Mr^io cor-.o-c<^rocooo o_o>oj o. t°i ^ CO r^od o'cSMiOCOiONCOOi M o" 4 lo tC lo oo" >o tC 4 m' 6 lo d CO "3 CNcor^Mvo M r^(N r^ OvoMior^C-ioOMOO- '^ -^ M M ". '^'^'^'^^^'^'C oo r-.ooo t^cocooooo o o O H M m" m CM^ cT P. h i2 n ~6~ o 00 lO ly^t^oo t^cs -^lor^N r^ooo -^o M t^ooo t^ 'J- o o o d t^ coco^ooo w O cs CJOO C^OO PI r^O O OOO^co : d " fi OvOO ■^OQvo lO-^vo CO-^C^ CH(NC . . . . O' . . . . '^ .... ^ .... "^ ^ ■ d .... o" ... . ^ ; : : : m' : ■ : : ° "3 p. . . . . ^0 . . . . N ^ ■ ■ ' ■ to ■ ■ ■ ' O o Ph r 6 1 2 » o c o" O CO OvOQOOO '^COMOOOO Ott^OO^coOoOiOM 00 o CM fJ 00 « io4co4>oioioN 4 comO rJ-rfcococor^O CM oi 00 O lO ft o % M X^ loio^o loco « TJ-OOOO r^o oio-*M coiOMOoo lOO f^ o "S r^ I^COCOOO M M ON M 'c^oo M COM oooo lo-cj-oo o o ^ C ri. o> aoo>i«>o>oo >o-o lO^t^OO loioiooo x^io lo CO o fi n o I-) c o o> o OrfMcOMQTfOM 01 rfMOO loOO CM Oco O N 00 Tf fO VO >OOMO TiOOO lONCC CO O ■^ h^ oco Mooco COM onq*q TfM'^fMCOOMt^f-.MO M 00 O t- _rt w '^ M M O.OOCOCOCOCO mcoOOoTmco^OO^ cX CO d 4 3 1^ CN O O cox^M voc^cooo «o O ^ocgo oco ^ ^00 r^ CO 00OOO>000mm CI CM COCOCOTf^lOiOiOVO lO O o o CO CO COCOCOCO-f'*-*4'f "f4'f-f44't44'*'f 4 4 4 4 p, ^ O M c^ co-^iovo r.^00 OO M (N co^ioo r^oo oo m CM CO "* !C sS 00 00 oooooooooooocooo a> oooooooooo o ° a 9. 9. 00 00 oooooooooooococooo cooocooooooooococo oo o o o o APPENDIX XVI. 395 TABLE VI. — TYPHOID FEVER DEATH-RATES IN CERTAIN CITIES OF FRANCE. (After Debauve-Imbeaux.) Name of City. Paris Lille Roubaix Rheims Nancy Lyon Saint-Etienne .... Marseille Toulon Nice Toulouse Bordeaux Rouen Le Havre Nantes Total for 56 cities of France . . . Population in 1901. 2,714,068 210,069 124,365 108,385 102,559 459,099 146,559 491,161 102,118 105,109 149,841 256,638 116,316 130,196 132,990 7,521,151 Typhoid Fever Death-rate per 100,000. 1886-1889 45-2 195 27.0 44.2 55-7 29-5 28.7 104.2 106. 2 85-7 80.2 62.0 72-5 195-5 51-7 52-1 For the year 1886 1890-1898 1899-1903 20. o 13-7 23-5 30-4 57-4 23.8 28.0 67-3 109. 2 51-8 35-8 19-3 09.8 17.2 28.6 31.2 21 . 1 23-9 40.7 95-9 30.7 24.8 17.4 40.6 87.0 36.2 21.2 For the year 1903. 396 TYPHOID FEVER. TABLE VII. — TYPHOID FEVER DEATH-RATES FOR CER- TAIN GERMAN CITIES PER 100,000. >> rj 1 1 i 1 a 1 (5 0. ;3 a S (J ti a ■S 'S :o i4 > c 1 a a 1885 16.3 34-0 21.3 17.2 13.8 15-9 131 13.0 42.4 9-3 7-2 6.8 1886 13 3 65-3 16.9 19.7 17 8 8.2 12.4 12.3 41.2 16.6 8-5 9.2 1887 13 6 85-9 15-6 9-3 10 8 9.0 II. 9 6.1 41.9 6.6 6.8 6.6 1888 12 8 52.2 14.6 9.8 9 8 6.7 9.4 8.3 80.9 10.4 8.2 6.5 1889 19 41.0 II. 2 9.4 7 7 "•3 16.7 8.6 17-5 II. 8 6.5 S-9 1890 9 I 26.2 14.8 8.0 7 6 II. 8 8.5 7.8 16. 1 7-3 2.1 9-5 I89I 10 4 26.2 II. 4 6.6 7 9 151 131 5-8 22. 7 5-2 7.0 13.2 1892 8 3 34-5 14.8 2.9 5 3 8.0 II. 4 7-5 13.8 6.1 4-7 9.8 1893 9 4 17.6 9.8 14.8 4 8 7.0 18.3 4.4 13-7 8.0 8.6 17.7 1894 4 2 6.0 6.8 2-5 8 9-7 6.7 6.3 16.4 7.2 S-8 5-8 189s 5 7 9.2 9.9 3-6 S I 8.3 8.4 5-2 8.1 6.4 4.4- 6-3 1896 4 7 5-4 7-1 3-2 4 3 7.6 5-8 4-5 16.0 6.8 6.2 7-5 1897 4 7-1 10.9 5-1 3 3 9.0 8.5 5-1 10. 1 3-6 1.2 31 1898 4 3 4.6 6.9 3-3 4 3 8.1 II. 4 1-5 9.9 S-8 3-7 4.4 1899 4 I 3-7 22.8 31 7 3 7.6 8.6 3-7 13.0 7-7 3-1 1900 5 8 3-4 10.6 4 I 4-3 I90I 4 7 6 4 1902 2 7 4 3-5 1903 3 2 5 3 1904 3 7 2 8 1905 5 3 3 7 3-2 3-7 APPENDIX XVI. TYP TABLE VIIT. TABLE SHOWING THE NUMBER OF DEATHS FI WHICH HAVE A POPULATION OF loo,ood Cities. Allegheny, Pa. Baltimore, Mo. Boston, Mass. Buffalo, N. Y. Chicago, 111. . Cleveland, Ohio Columbus, Ohio Denver, Colo. Detroit, Mich. . Fall River, Mass. Indianapolis, Ind. Jersey City, N. J. Kansas City, Mo. Los Angeles, Cal. Louisville, Ky. . . Memphis, Tenn. . Milwaukee, Wis. . Minneapolis, Minn Newark, N. J. . . New Haven, Conn New Orleans, La. New York, N. Y. Manhattan Bronx . . Brooklyn . Queens . Richmond Omaha, Neb.. Paterson, N. J. . Philadelphia, Pa. Pittsburg, Pa. Providence, R. I. Rochester, N. Y. San Francisco, Cal Scranton, Pa. St. Joseph, Mo. . St. Louis, Mo. . St. Paul, Minn. Syracuse, N. Y. Toledo, Ohio Washington, D. C. Worcester, Mass. . Cincinnati, Ohio . Population. 78,582 362,839 155.134 503.185 160,146 51.647 35.629 116,340 48,961 75.056 120,722 55.185 11,183 123,151 33.592 115.587 46,887 136,508 62,i 216,090 1,897,712 1,164,673 41,626 599,495 52.927 38,991 30,518 51,031 847,170 156,389 104,857 89,366 233,959 45,850 32,431 350,518 41,473 51,792 50,137 177,624 58,291 296,908 105,287 434,439 448,477 255,665 ,099,850 261,353 88,150 106,713 205,876 74,398 105,436 163,000 132,716 50,395 161,129 64,495 204,468 164,738 181,830 81,298 242,439 2,487,840 1,441,216 74.085 838,547 82,299 51.693 140,452 78.347 1,046,964 238,617 132,146 133,896 298,997 72,215 52,324 451,770 133,156 88,143 81,434 230,392 84,655 255,139 129,896 508,957 560,892 352,387 ,698,575 381,768 125,560 133.859 285,704 104,863 169,164 206,433 163,752 102,419 204,731 102,320 285,315 202,718 246,070 108,027 287,104 3,437,202 1,850,093 200,507 1,850,093 152,999 67,021 102,555 105,171 1,293.697 321,616 175,597 162,608 342,782 102,026 102,979 575,238 163,065 108,374 131,822 278,718 118,421 128,135 142,848^ 546,217 595-380 372,088 1,932,315 425,632 142,105 150,317* 325,563* 105,762 212,198 232,699 179,272* 200,000 222,660* 121,235* 312,948* 261,974* 283,289 119,027* 309,639* 4,000,403* 2,102,928 271,592 1,355,106 197,838 72,939 120,565* 111,529 1,850,093 364,161 198,635* 182,022 364.677 116,111* "5.479* 636,973* 191,023 117,129* 155,887 302,883* 1880 1881 44 196 154 171 70 35 43 98 197 207 no 568 169 32 79 135 59 116 165 212 121 462 51 156 119 42 61 26 98 63 361 123 33 33 51 41 151 216 82 354 121 26 116 155 47 69 155 152 47 496 71 32 152 29 44 94 17 38 372 594516625 476 405: The figures for th 71 99 93 92 107 153 26 32 498:645 II 2 53 38 26 90 139 325.902 341,444 178 191 91 153 38 650 268 140 30 152 166 579 188 128 39 163 26 16 662 130 52 49 150 25 166 60 77 123 21 28 183 146 20 . . . 118 153 136 152 21 610 154 44 32 118 33 125 44 14 16 134 19 116 * U. S. Census Estimate. )ID FEVER STATISTICS. M TYPHOID FEVER IN THE CITIES OF THE UNITED STATES )R OVER FOR THE YEARS l88o TO 1906. Deaths from Typhoid Fever by Years. il887 1888 1889 1880 1891 1892 1893 1894 1895 1896 189^ 189[ ]\m 19Ct 1901 1905 i9o: 1904 190c 1906 ■ no 106 106 146 96 171 161 99 227 59 7S 73 135 121 135 I4S 12^ i6e 182 187 ■156 161 191 247 150 193 22,^ 222 173 1 88 185 185 153 i8g 141 22c 185 195 197 183 183 170 186 155 154 137 148 141 163 162 173 185 165 143 142 139 iig 135 117 122 77 68 73 105 129 98 112 185 87 68 69 9S 87 9c 98 125 ^33 91 9c 90 382 375 453 1008 1997 1489 670 491 518 751 437 636 442 337 509 801 588 373 329 370 120 113 185 180 137 167 ^53 89 117 143 79 121 118 205 140 ^33 472 204 67 93 36 65 48 45 46 47 56 49 29 33 31 53 47 44 46 195 109 52 lOI 134 188 287 99 64 71 59 43 91 63 41 49 43 48 65 60 45 52 98 116 86 62 39 73 209 97 67 56 57 38 58 35 50 58 60 53 5° 45 70 45 46 48 209 49 27 62 33 30 25 32 21 II 15 21 14 27 19 II 9 52 no 56 140 80 64 65 74 79 63 88 108 122 412 75 81 114 132 159 ^67 123 116 96 174 158 38 79 41 39 44 60 33 71 33 44 60 36 132 53 46 70 54 45 98 54 45 52 45 35 37 19 '28 22 '36 43 31 "28 25 44 41 47 44 120 133 144 142 130 116 135 145 126 131 93 126 132 106 104 108 157 112 113 137 42 45 37 35 45 21 22 41 32 32 28 23 39 36 44 34 45 55 34 34 55 78 55 83 71 66 80 60 63 46 31 46 47 59 63 48 54 43 68 95 156 114 65 100 84 146 lOI 86 67 157 89 77 79 132 65 lOI 103 55 87 '84 76 131 194 134 153 63 43 43 61 44 31 85 25 53 50 61 38 40 53 24 38 24 24 18 26 28 28 32 28 25 36 30 28 107 43 42 31 49 63 34 46 41 50 59 SI 39 76 113 90 141 184 676 353 155 546 278 114 718 342 141 728 380 135 764 365 119 653 317 III 661 lOI 649 273 95 639 325 421 364 397 352 384 400 381 326 322 297 299 277 ronx are included in th ose fo'- Manhattan 23 16 30 32 34 33 32 37 44 143 153 161 182 180 162 179 159 173 163 173 270 16 205 27 20 301 32 13 24 272 27 16 322 32 I I 267 22 303 34 15 19 297 31 II 230 30 10 14 32 14 II 97 63 46 50 28 19 22 40 29 18 22 26 23 20 32 48 16 19 18 18 15 33 28 21 47 49 35 34 49 27 36 24 7 16 6 621 785 736 666 683 440 450 370 469 402 401 639 948 449 444 588 744 957 684 1063 269 191 218 315 249 256 292 152 213 175 184 218 342 464 416 475 474 503 380 519 39 103 59 39 62 51 50 70 46 40 24 39 42 41 47 36 37 28 35 39 38 54 39 43 50 71 58 18 43 26 35 19 32 30 31 19 21 29 19 31 64 93 160 ^33 128 99 99 118 108 85 62 136 74 46 77 98 10 100 91 9 31 20 18 28 33 24 21 33 24 15 14 25 32 24 18 13 13 22 '64 17 22 19 28 22 14 12 14 9 9 10 10 1^6 ^33 140 137 172 514 171 172 100 118 119 99 149 168 198 222 287 215 124 112 145 135 lOI 74 65 57 59 37 41 43 25 41 32 39 24 24 18 27 20 41 20 27 22 29 40 33 34 41 31 30 24 45 26 31 20 10 6 12 18 II 23 25 28 38 23 35 25 31 40 37 37 31 40 51 40 52 40 56 71 70 167 188 213 257 186 216 202 228 235 148 130 191 199 220 172 226 140 135 140 161 13 2 25 15 18 19 31 31 25 14 15 13 19 32 26 18 17 5 27 IS 403 203 142 205 186 121 ^34 169 120 164 lOI 105 121 119 182 206 150 270 155 239 TABL TABLE SHOWING THE NUMBER OF DEATHS FROM TYPHOID POPULATIONS BETWEEN 50,000 AND Cities. Albany, N. Y. . . Atlanta, Ga. . . . Bridgeport, Conn. Cambridge, Mass.. Camden, N. J. . . Charleston, S. C. . Dayton, Ohio . . Des Moines, Iowa Duluth, Minn. . . Elizabeth, N. J. . . Erie, Pa Evansville, Ind. Grand Rapids, Mich Harrisburg, Pa. Hartford, Conn. . Hoboken, N. J. Kansas City, Kas. Lawrence, Mass. . Lowell, Mass. . . Lynn, Mass. . . . Manchester, N. H. Nashville, Tenn. . New Bedford, Mass, Oakland, Cal. . . Peoria, 111 Portland, Me. . Pordand, Ore. . Reading, Pa. . . Richmond, Va. . Salt Lake City, Utah San Antonio, Tex. Savannah, Ga. . Seattle, Wash. . , Somerville, Mass. . Springfield, Mass. Trenton, N. J. . Troy, N. Y. . . Utica, N. Y. . . Wilkesbarre, Pa. Wilmington, Del. Population. 3o>75 37.409 27,649 52,669 41,659 49,984 38,678 22,4 28,229 27>737 29,280 32,016 30,762 42,015 3,200 39>i5i 59,475 274 32,630 43,350 26,845 34,555 29,259 33,810 17,577 43,278 63,600 20,768 20,550 30,709 3,533 24,933 33,340 94,923 65,533 48,866 70,028 58,313 54,955 61,220 50,093 33,115 37,764 40,634 50,756 60,217 39,385 53,230 30,999 43, M 38,316 44,654 77,696 55,727 29,110 56,747 •33,914 42,478 44,126 71,168 40,753 48,682 41,024 36,426 46,385 58,661 81,388 44,243 37,673 43 42,»37 40,152 44,179 57,458 60,956 44,007 37,718 61,431 94,151 89,872 70,996 91,886 75,935 55,807 85,333 62,139 52,969 52,130 52,733 59,007 87,565 50,167 79,850 59,364 51,418 62,559 94,969 513 56,987 80,865 62,442 66,960 56,100 50,145 90,426 78,961 85,050 53,531 53,321 54,244 80,671 61,643 62,059 73,307 60,651 56,383 51,721 76,508 79,848* 102,70 82,061* 96,324 81,877 56,147* 98,350 75,626* 64,942* 60,509 58,783 63,132 97,756* 54,807 93,160* 65,468 67,614* 70,050 94,889 77,042* 63,417* 84,227* 74,362 72,670* 65,026* 54,330* 104,141* 89,111 86,880* 58,914 61,146* 67,311 99,586* 69,272 73,540 76,271* 63,647* 58,721* 83,860* 1880 1881 1882 1883 1884 1885 18! 13 32 17 27 26 58 38 14 39 24 72 43 49 31 13 17 20 43 16 120 16 2; 51 45 * U. S. Census Estimated. [X. :VER IN THE CITIES OF THE UNITED STATES WHICH HAVE i,ooo FOR THE YEARS 1 880 TO 1906. Deaths from Typhoid Fever by Years. 87 1888 1891 1892 1893 1894 1895 1896 1897 1898 1899|1900il901 1902il903 1904 1905'1906 74 105 8 27 55 30 40 15 18 26 15 62 IC 99 3 17 56 24 41 58 63 12 16 38 24 46 22 53 24 33 50 57 28 32 14 15 10 17 30 lOI 14 21 96 33 25 36 97 30 3 44 47 14 112 8 19 27 9 9 30 94 82 38 56 77 52 10 14 23 73 18 17 77 8 20 49 61 31 13 34 22 7 5 66 83 18 17 16 29 19 36 7 13 42 48 44 35 33 37 14 35 24 19 17 14 19 12 16 13 17 20 66 10 II 45 29 42 28 30 39 6 10 17 26 34 7 32 60 125 21 28 13 14 16 10 7 19 20 46 30 49 88 II 25 II 55 15 35 28 58 20 14 39 15 27 20 29 44 29 39 27 36 12 29 26 II 16 28 9 15 14 17 36 20 45 29 23 20 II 18 17 13 13 15 52 18 24 15 15 33 48 9 ■46 39 22 13 23 19 33 40 75 14 23 16 24 9 17 26 76 36 38 19 6 15 15 23 35 32 20 33 17 26 12 16 14 42 9 32 17 34 55 37 31 23 26 29 6 13 29 37 41 17 17 13 46 12 15I 30 15 14 17 7 16 14 15 34 3c 51 36 34 33 10 17 45 25 15 25 29 34 27 30 51 35 6 63 8 29 9 35 34 41 35 36 54 36 34 43 37 II 16 34 28 19 34 INDEX. PAGE Aeration in streams • 55 Age ■ 103 Agglutination 11, 320 Albany, N. Y 77, 123, 238, 263, 276, 280, 369 Alcoholic beverages 91 Algae growths 58 Allegheny, Pa 158 Allied diseases 6, 222, 278 Animals not susceptible to typhoid fever 10, 11 Army camps 68 Artificial ice 62 Atlantic coast 114 Augusta, Me 154, 260, 369 Auxerre, France 185, 369 Bacillemia in typhoid fever 325 Bacillus typhosus (B. typhi) 1-8, 314, 322, 332, 337, 344 Bacteriology of typhoid fever 8 Baltimore, Md 122, 124, 259 Bangor, Me 178, 260 Baraboo, Wis 179, 369 Barriers against spread of typhoid fever 22, 23, 28, 34 Barnes' Well, Ithaca 226 Basingstoke, England 183 Beaches 120 Berlin, Germany 394 Binghamton, N. Y 77, 242, 280 Blood, in typhoid fever 13 Blood tests 17. 35 Bloomfield, N. J 204 Board of Health 26, 70, 84 Boats, pollution from 238 397 398 INDEX. PAGE Boiling water 86, 289 Boston, Mass 122, 124, 252, 388 Bowers, George 176 Breath 19 Brooklyn, N. Y 256 Bulstrode, Dr 206 Burlington, Vt 171, 369 Butler, Pa. . . . : 193, 369 Buxton, Dr. B. H 13, 322 Canadian cities 393 Carbolic acid 29, 289, 292 Carriers of typhoid fever 19, 213 Caterham, England 369 Cause of typhoid fever .....' 10, 21, 131 Celery 209 Census data 100, 303 Certified milk 79 Cesspools 32, 65, 290 Cesspools, fate of typhoid bacillus 52 Charleston, S. C 122 Chemical disinfection 289 Chicago Drainage Canal 51, 162, 246 Chicago, III 122, 161, 164, 369,391 Children 6, 33, 106, 108 Chloride of lime 29, 289, 291 Cholera 7 Chronological distribution 128 Classification of epidemics 135 Cleanliness 32, 78, 85 Clean water and how to get it 248 Cleveland, Ohio 166, 235, 369 Climate 114 Cockles 209 Coleman, Dr. Warren 13, 322 Collection of typhoid data 217 Colored race m Columbus, Ohio 369 Complications in typhoid fever S> 97 Conduits, purification of water in 60 INDEX. 399 PAGE Conn, Dr. H. W 20^ Contagion ' 23, 148 Contaminated waters 230, 282 Control of epidemics ' 223 Convalescence 5> 33 Copper sulphate 224, 294 Cornell University ■ j^2 Corrected death-rates 707 Corrosive sublimate 29, 280 293 Cost of typhoid fever 27<; 367 Currents in lakes i?? iiO Data, collection of 218 Data, study of 210 Date of infection 220 Dead ends ' 53 Death-rates 03 94 91; Defense, lines of, against the typhoid bacillus 69, 70, 85, 89 Defenses of the body against typhoid fever ir Delaware River 246 Depreciation of polluted water 278 Diagnosis of typhoid fever 2, 317 Diazo reaction ,20 Diet jjo Dilution r^ Disinfectants 29 287 Disinfection 25, 28, 35, 287 Disinfection of water supplies 224 Dispersion in lakes cy Distribution of typhoid fever jo? Drigalski-Conradi Agar ,7, Duration of typhoid fever e Dust 42 Dysentery » II Eberth bacillus , • Educational work 84 Emsworth, England 206 Endless chain ' 21 England 129 400 INDEX. PAGE Entry of typhoid bacilli into the body 12 Epidemics 134, 209, 214 Errors in death-rates 96 European death-rates 116, 117 Exit of typhoid bacilli from the body 17 Fabrics, typhoid fever in 68 Far Rockaway, L. 1 206 Fatality of typhoid fever 96, 99, 105 Fecal matter, disposed of 31, 38 Feces, typhoid bacilli in 49 Filters, house 86 Filtration of water 73> 77; 247, 276 Financial aspect of typhoid fever 273 Fire connections 177, 178 Flies 39, 67, 88, 198, 296 Flies, epidemic due to 135, 191, 196 Focus of infection 21 Food of typhoid bacillus 45 Food supplies, supervision of 83 Formaldehyde 294 France, cities of 395 Frankfort-on-the-Main 231 Freezing 45 Fruit, epidemic due to 136, 207, 209 Fuertes, James H 228 Fulton, John S 96, 113 Fumigation 294 Gastric juice 12 Gelsenkirchen 148 Geological distribution 119 Geographical ^ 115 German cities 71, 396 Glasgow, Scotland 268 Gorgas, Col. W. C i97 Ground waters 74, 185, 186, 188 Hamburg, Germany 235 Hansen, Paul 248 INDEX. 401 PAGE Hazen, Allen 248, 277 Health tone , 89 Heat, as a germ destroyer 288 Horton, Theodore 251 Howard, Dr. L. 296 Hudson River 238, 260, 263, 369 Hydrographic distribution 120 Hypersensitiveness 14 Ice, epidemic due to 136, 208 Ice, handling of 63 Ice, longevity of typhoid bacillus 61, 62 Immunity to second attack 109 Incubation period 2, 220 Infection, vehicles of 22 Inspected milk 79 Intestinal disinfectants 24 Intestinal disorders 14 Investigation of epidemics 216 Iron sulphate 294 Isolation '- ^^ Ithaca 142, 214, 226, 369 Jackson, D. D 121-300 Japanese-Russian War 197, 362 Japanese water supplies 117 Jersey City, N. J 233 Jordan, Dr. E. 193 Kennebec River 154, 263 Lake steamer, outbreak on 179 Lausen, Switzerland 181, 369 Lawrence, L. 1 206, 369 Lawrence, Mass 77, 149, 152, 236, 261, 279, 370 Leighton, M. 273 Lemon juice, effect on typhoid bacillus 91 Levy, Dr. E. C 154, 337, 371 Life-savers 214 Lime 30, 289, 290 402 INDEX. PAGE Limestone regions and typhoid fever 120, 183 Lincoln, England 106 Literature of typhoid fever 368 Liverpool, England 270 London, England 124, 269, 394 Longevity of the typhoid bacillus. . . 46, 50, 63, 65, 66, 67, 68, 344 Lorain, Ohio 261 Lowell, Mass 149, 152, 174, 235, 370 Lynch, Major Charles 197 Malaria 96 Manila, Philippine Islands 118, 119 Marine Hospital Service 272 Marlborough, Mass 202, 370 Medicine in peace and war 362 Merrimac River 150, 176, 263 Messalonskee stream 157 Microscopic organisms, effect on typhoid bacillus 58 Middletown, Conn 204, 370 Military camps . 195, 356 Milk, dangers from diet 78, 126, 268 Milk, epidemic due to 136, 198, 199, 201, 202, 204 Milk, longevity of typhoid bacillus 65 Milk supplies and death-rates 267 Millinockett, Me 177 Mississippi River 243, 265 Moisture 42 Monongahela River 159 Montclair, N. J 204, 285, 370 Morbidity statistics 99 Mount Savage, Md 188 Multiplication of typhoid bacilli in the body 12 Musca domestica 296 National Department of Health 284 Newark, N. J 232, 370 New Haven, Conn 140, 219, 370 New Haven jail 191 Newport, R. I ■ . 185, 220, 370 New York City 121, 122, 123, 124, 254 INDEX. 403 PAGE New York Department of Health 317 Northwest, epidemic on Steamer 180, 212 Nostrums 91 Nurse, duty of 24 Occupation 112 Ogdensburg hospital 208 Ohio River 265 Oysters 66, 80 Oysters, epidemics due to 136, 204, 206 Oxidation in streams 55 Panama * 196 Parasites 14 Parathyphoid fever 7 Paris, France 243, 394 Parker, Horatio N 190 Passaic River 232, 242 Pasteurized milk 79, 87, 267 Paterson, X. J 242, 370 Pearse, Langdon 154 Pease, Dr. H. D 344 Penobscot River 178, 263 Personal responsibility 89 Perspiration 19 Peyer^s patches 12 Phelps, Prof. Earle B 187 Philadelphia, Pa 77, 122, 246, 370 Phihppine Islands, t}-phoid fever in 117, 118 Physician, dut\' of 23 Pipes, purification of water in 60 Pittsburg, Pa 122, 15S, 283, 367, 370 Plymouth, Pa 136, 370 Pollution of streams 263 Population, estimation of 303 Portals of entr)- 12 Port Deposit, Md 209 Portland, Me 130 Potomac River 120, 1S9, 265 Poughkeepsie, X. Y 260, 370 404 INDEX. PAGE Prescott and Winslow 332 President's message 361 Price, Dr. M. L 190 Public authorities 34, 70 Pure water, value of 273 Quarantine 33 Race no Railroad car toilet rooms 38 Registration area 112 Rennes, France 208 Report to Board of Health 26, 34, 70 Residual typhoid fever 132 Resistant minority 47, 52, 213 Richmond, Va 154, 156 Roosevelt, President 361 Rosenau, Dr. M. J ■ 2151 Rural 112, 215, 371 Saliva 19 San Francisco, Cal 124 Sanitary supervision of watersheds 75 Sanitiage de Chile 124 Savage 332 Schenectady, N. Y 263 Schuylkill River ' 246 Scranton, Pa 145, 371 Screens 32, 87 Seaman, Dr. Louis L 198, 362 Seasonal distribution 121, 126 Sedimentation 54, 57 Sedgwick, Prof. William T 61, 125, 150, 199, 251 Self-purification of lakes and reservoirs 56 Self-purification of streams 53, 56 Sewage disposal 36 Sewage, longevity of the typhoid bacillus 50, 51 Sewage purification 52, 265 Sewer gas 36, 43 INDEX. 405 PAGE ■5^^ • 109 Shenandoah Valley 120 Shiga bacillus ^ Smith, Herbert E 140, 191, 202 Soil bacteria 54 Soil, typhoid bacillus in 6^ Somerville, Mass 108, 220 Soper, Dr. Geo. A 142, 174, 207 South America, typhoid fever no Southampton, England 2015 South-end, London 209 Southern states 114, 11 c 2?o Spanish War 129, 195, 214, 256, 258 Spleen ^ Springfield, Mass 76,199,207,371 Spring waters ^g Stagnation of lakes ry Stamford, Conn 108, 142, 201, 371 Standards of purity - . Statistics 71, 92, 98 St. Louis, Mo loj^ 24^ Sterilization 288 Storage, effect on quality of water ';8 eg Sunlight '44 Surface waters » - Susquehanna River 261; Switzerland, Lausen jgj Symptoms ^^ 2^ Taylor, L. H j,^ Temperature, effect on typhoid bacillus 4c Temperature of body in typhoid fever , Time, influence on longevity of B. typhi ee Tobacco Q Toilet rooms _„ Traveling, risks of qq Treatment of typhoid fever e 24 Trenton, N. J ^gg Troy, N. Y 276 Typhoid bacillus 8, 314, 322, 332, 337, 344 406 INDEX. PAGE Typhoid bacillus at large 41 Typhoid carriers '. 19 Typhoid fever, typical case 2 Typhoid Mary 20 Typho-toxin 15 United States army camps 195, 356, 362, 37 United States, cost of typhoid fever 275 United States Navy 196 Urban typhoid 112 Urine affected in typhoid fever 18, 24, 294, 320 Urotropin 24, 294 Vacation typhoid 127 Value of human life 273 Value of pure water 273 Vehicles of infection 22, 84 Vended waters 78 Viability of typhoid bacillus 46, 344 ' Vienna 394 Wainright, Dr 147 Walking cases ■ 6, 20 Warnings of epidemics 211 Washington, D. C 112, 122, 127, 191, 248, 270,371 Water analyses 76, 222,332,337 Waterbury, Conn 76, 202 Water cresses 209 Water, epidemics due to 13S) 228 Water filtration 73-265 Water, longevity of typhoid 46 Water supplies 72, 74, 221, 228 Watertown, N. Y 77, 242, 280, 371 Waterville, Me 108, 154, 371 Waves of typhoid 265 Well water 85 Wesleyan University 204 Widal test • - • 16, 317 Williams College 208, 371 Winchester, England ■ 205 INDEX. 407 PAGE Wing, Frank E 367 Winnipeg, ^lanitoba 102, 220, -571 Winslow, Prof. C. E. A 61, 125, 185 Youngstown, Ohio 249 Zinc, chloride 294 Zurich, Switzerland 235 SHORT-TITLE CATALOGUE or THE PUBLICATIONS OF JOHN WILEY & SONS, New York. LoNDOiir: CHAPMAN & HALL, Limited. ARRANGED UNDER SUBJECTS. Descriptive circulars sent on application. Books marked uitli an asterisk (*) are sold at net prices only. All books are bound in cloth unless otherwise stated. AGRICULTURE. Armsby's Manual of Cattle-feeding i2mo, Si 75 Principles of Animal Nutrition 8vo, 4 00 Budd and Hansen's American Horticultural Manual: Part I. Propagation, Culture, and Improvement i2n:o, i 50 Part II. 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Rewritten Edition. i6mo,mor., 5 co Merrill's Stones for Building and Decoration 8vo, 5 00 Non-metallic Minerals: Their Occurrence and Uses 8vo, 4 00 Monckton's Stair-building 4to, 4 00 Patton's Practical Treatise on Foundations. 8vo, 5 00 Peabody's Naval Architecture 8vo, 7 50 Rice's Concrete-block Manufacture 8vo, 2 00 Richey's Handbook for Superintendents of Construction i6mo, mor., 4 00 * Building Mechanics' Ready Reference Book : * Carpenters' and Woodworkers' Edition i6nio, morocco, i 50 * Cementworkers and Plasterer's Edition. (In Pres.s.) * Stone- and Brick-mason's Edition i2mo, mor., i 50 Sabin's Industrial and Artistic Technology of Paints and Varnish 8vo, 3 00 Siebert and Biggin's Modern Stone-cutting and Masonry 8vo, 1 50 Snow's Principal Species of Wood 8vo, 3 50 Sondericker's Graphic Statics with Applications to Trusses, Beams, and Arches. 8vo, 2 00 Towne's Locks and Builders' Hardware i8mo, morocco, 3 00 Turneaure and Maurer's Principles of Reinforced Concrete Construc- tion 8vo , 3 00 Wait's Engineering and Architectural Jurisprudence Svo, 6 00 Sheep, 6 50 Law of Operations Preliminary to Construction in Engineering and Archi- tecture Svo, 5 00 Sheep, 5 50 Law of Contracts Svo, 3 00 Wilson's Air Conditioning, (In Press.) Wood's Rustless Coatings: Corrosion and Electrolysis of Iron and Steel. .8vo, 4 00 Worcester and Atkinson's Small Hospitals, Establishment and Maintenance, Suggestions for Hospital Architecture, with Plans for a Small Hospital. i2mo, I 25 The World's Columbian Exposition of 1893 Large 4to, 1 00 ARMY AND NAVY. Bernadou's Smokeless Powder, Nitro-cellulose, and the Theory of the Cellulose Molecule i2mo, 2 50 Chase's Screw Propellers and Marine Propulsion Svo, 3 00 Cloke's Gunner's Examiner Svo, i 50 Craig's Azimuth 4to, 3 50 Crehore and Squier's Polarizing Photo-chronograph Svo, 3' 00 * Davis's Elements of Law " Svo, 2 50 * Treatise on the Military Law of United States Svo, 7 00 Sheep, 7 50 De Brack's Cavalry Outposts Duties. (Carr.) 24mo, morocco, 2 00 Dietz's Soldier's First Aid Handbook i6mo, morocco, 1 25 "= Dudley's Military Law and the Procedure of Courts-martial.. . Large lanio, 2 50 Durand's Resistance and Propulsion of Ships Svo, 5 00 2 4 oo 6 00 6 oo 7 50 1 50 2 00 4 00 5 00 S 00 10 I 00 7 so 2 50 * Dyer's Handbook of Light Artillery i2mo, 3 Eissler's Modern High Explosives 8vo, 4 * Fiebeger's Text-book on Field Fortification Small 8vo, 2 Hainilton's The Gunner's Catechism i8mo, i * Hoff's Elementary Naval Tactics 8vo, i Ingalls's Handbook of Problems in Direct Fire 8vo, * Lissak's Ordnance and Gunnery 8vo, * Lyocs's Treatise on Electromagnetic Phenomena. Vols. I. and H. .8vo, each, * Mahan's Permanent Fortifications. (Mercur.) 8vo, half morocco, Manual for Courts-martial i6nio, morocco, * Mercur's Attack of Fortified Places i2mo, * Elements of the Art of War 8vo, Metcalf's Cost of Manufactures — And the Administration of Workshops. .8vo, * Ordnance and Gunnery. 2 vols i2mo, Mtirray's Infantry Drill Regulations ' i8mo, paper, Nixon's Adjutants' Manual 24ino, Peabody's Naval Architecture 8vo, * Phelps's Practical Marine Surveying 8vo, Powell's Army Officer's Examiner i2mo, 4 00 Sharpe's Art of Subsisting Armies in War i8mo, morocco, i 50 * Tapes and Poole's Manual of Bayonet Exercises and Musketry Fencing. 24nio, leather, 50 Weaver's Military Explosives 8vo, 3 00 Wheeler's Siege Operations and Military Mining 8vo, 2 00 Winthrop's Abridgment of Military Law i2mo, 2 50 WoodhuU's Notes on Military Hygiene i6mo, i 50 Young's Simple Elements of Navigation i6ino, morocco, 2 00 ASSAYING. Fletcher's Practical Listructions in Quantitative Assaying with the Blowpipe. i2mo, morocco, i 50 Furman's Manual of Practical Assaying 8vo, 3 00 Lodge's Notes on Assaying and Metallurgical Laboratory Experiments. . . .8vo, 3 00 Low's Technical Methods of Ore Analysis. 8vo, 3 00 MiUer's Manual of Assaying i2mo, i 00 Cyanide Process i2mo, i 00 Minet's Production of Aluminum and its Industrial Use. (Waldo.) i2mo, 2 50 O'DriscoL's Notes on the Treatment of Gold Ores 8vo, 2 00 Ricketts and Miller's Notes on Assaying 8vo, 3 00 Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 4 00 Ulke's Modern Electrolytic Copper Refining 8vo, 3 00 Wilson's Cyanide Processes i2ino, i 50 Chlorination Process i2mo, 1 50 ASTRONOMY. Comstock's Field Astronomy for Engineers 8vo, 2 50 Craig's Azimuth 4to, 3 50 CrandaU's Text-book on Geodesy and Least Squares 8vo, 3 00 Doolittle's Treatise on Practical Astronomy 8vo, 4 00 Gore's Elements of Geodesy 8vo, 2 50 Hayford's Text-book of Geodetic Astronomy 8vo, 3 00 Merriman's Elements of Precise Surveying and Geodesy 8vo, 2 50 * Michie and Harlow's Practical Astronomy 8vo, 3 00 * White's Elements of Theoretical and Descriptive Astronomy i2mo, 2 00 3 BOTANY. Davenport's Statistical Methods, with Special Reference to Biological Variation. i6mo, morocco, i 25 Thom^ and Bennett's Structural and Physiological Botany i6mo, 2 25 Westermaier's Compendium of General Botany. (Schneider.) 8vo, 2 00 CHEMISTRY. * Abegg's Theory of Electrolytic Dissociation. (Von Ende.) i2mo, i 25 Adriance's Laboratory Calculations and Specific Gravity Tables i2mo, i 25 Alexeyeff's General Principles of Organic Synthesis. (Matthews.) 8vo, 3 00 Allen's Tables for Iron Analysis 8vo, 3 00 Arnold's Compendium of Chemistry. (Mandel.) Small Svo, 3 50 Austen's Notes for Chemical Students i2mo, i 50 Beard's Mine Gases and Explosions. (In Press. ) Bernadou's Smokeless Powder. — Nitro-cellulose, and Theory of the Cellulose Molecule i2mo , 2 50 Bolduan's Immune Sera 12mo , i 50 * Browning's Introduction to the Rarer Elements Svo, i 50 Brush and Penfield's Manual of Determinative Mineralogy Svo, 4 00 * Claassen's Beet-sugar Manufacture. (Hall and Rolfe.) Svo, 3 00 Classen's Quantitative Chemical Analysis by Electrolysis. (Boltwood.). .Svo, 3 00 Cohn's Indicators and Test-papers i2mo, 2 00 Tests and Reagents Svo, 3 00 Crafts's Short Course in Qualitative Chemical Analysis. (Schaeffer.). . .i2mo, i 50 * Danneel's Electrochemistry. (Merriam.) i2mo, i 25 Dolezalek's Theory of the Lead Accumulator (Storage Battery). (Von Ende.) i2mo, 2 50 Drechsel's Chemical Reactions. (Merrill.) i2mo, 1 25 Duhem's Thermodynamics and Chemistry. (Burgess.) Svo, 4 00, Eissler's Modern High Explosives Svo, 4 00 Effront's Enzymes and their Applications. (Prescott.) Svo, 3 00 Erdmann's Introduction to Chemical Preparations. (Dunlap.) i2mo, 1 25 * Fischer's Physiology of Aliinentation Large i2mo, 2 00 Fletcher's Practical Instructions in Quantitative Assaying with the Blowpipe. i2mo, morocco, i 50 Fowler's Sewage Works Analyses i2mo, 2 00 Fresenius's Manual of Qualitative Chemical Analysis. (Wells.) Svo, 5 00 Manual of Qualitative Chemical Analysis. Part I. Descriptive. (Wells.) Svo, 3 00 Quantitative Chemical Analysis. (Cohn.) 2 vols Svo, 12 50 Fuertes's Water and Public Health i2mo, i 50 Furman's Manual of Practical Assaying Svo, 3 00 * Getman's Exercises in Physical Chemistry i2mo, 2 00 Gill's Gas and Fuel Analysis for Engineers i2mo, i 25 * Gooch and Browning's Outlines of Qualitative Chemical Analysis. Small Svo, i 25 Grotenfelt's Principles of Modern Dairy Practice. (WoU.) i2mo, 2 00 Groth's Introduction to Chemical Crystallography (Marshall) i2mo, i 25 Hammarsten's Text-book of Physiological Chemistry. (Mandel.) Svo, 4 00 Hanausek's Microscopy of Technical Products. (Winton. ) svo, 5 00 * HasMn's and MacLeod's Organic Chemistiy 12mo, 2 06 Helm's Principles of Mathematical Chemistry. (Morgan.) i2mo, i 50 Bering's Ready Reference Tables (Conversion Factors) i6mo, morocco, 2 50 Herrick's Denatured or Industrial Alcohol , Svo, 4 00 Hind's Inorganic Chemistry Svo, 3 00 * Laboratory Manual for Students i2mo, 1 00 Holleman's Text-book of Inorganic Chemistry. (Cooper.) Svo, 2 50 Text-book of Organic Chemistry. (Walker and Mott.) Svo, 2 50 * Laboratory Manual of Organic Chemistry. (Walker.) i2mo, i 00 4 HoUey and Ladd's Analysis oi Mixed Paints, Color Pigments . and Varnishes. (InPres;; Hopkins's Oil-chemists' Handbook 8vo, 3 00 Iddings's Rock Minerals . 8vo, 5 00 Jackson's Directions for Laboratory Work in Physiological Chemistry. .8vo, i 25 Johannsen's Key for the Determination of Rock-forming Minerals in Thin Sec- tions. In Press) Keep's Cast Iron 8vo, 2 50 Ladd's Manual of Quantitative Chemical Analysis i2mo, i 00 Landauer's Spectrum Analysis. (Tingle.) Svo, 3 00 * Langworthy and Austen. The Occurrence of Aluminium in Vegetable Products, Animal Products, and Natural Waters 8vo, 2 00 Lassar-Cohn's Apphcation of Some General Reactions to Investigations in Organic Chemistry. (Tingle. ; i2mo, i 00 Leach's The Inspection and Analysis of Food with Special Reference to State Control Svo, 7 50 Lob's Electrochemistry of Organic Compounds. (Lorenz.) Svo, 3 00 Lodge's Notes on Assaying and Metallurgical Laboratory Experiments. .. .8vo, 3 00 Low's Technical Method of Ore Analysis Svo, 3 00 Lunge's Techno-chemical Analysis. (Cohn.) i2mo i 00 * McKay and Larsen's Principles and Practice of Butter-making Svo, i 50 Maire's Modem Pigments and their vehicles. ' In Press.) Mandel's Handbook for Bio-chemical Laboratory i2mo, i 50 * Martin's Laboratory Guide to Qualitative Analysis with the Blowpipe . . i2mo, 60 Mason's Water-supply. ' Considered Principally from a Sanitary Standpoint. ) 3d Edition, Rewritten Svo, 4 00 Examination of Water. (Chemical and BacteriologicaL) i2mo, 1 25 Matthew's The Textile Fibres. 2d Edition, Rewritten - Svo, 400 Meyer's Determination of Radicles in Carbon Compounds. (Tingle.). .i2mo, i 00 Miller's Manual of Assaying i2mo, i 00 Cyanide Process i2nio, i 00 Minet's Production of Aluminum and its Industrial Use. (Waldo.) .... i2mo, 2 50 Mixter's Elementary Text-book of Chemistry i2mo, i 50 Morgan's An Outline of the Theory of Solutions and its Results i2mo, i 00 Elements of Physical Chemistry i2ino, 3 00 * Physical Chemistry for Electrical Engineers i2mo, 5 00 Morse's Calculations used in Cane-sugar Factories i6mo, morocco, i 50 * Mu'r's H'story of Chemical Theories and Laws Svo, 4 00 MulHken's General Method for the Identification of Pure Organic Compounds. VoL I Large Svo, 5 00 O'DriscoU's Notes on the Treatment of Gold Ores 8vo, 2 00 Ostwald's Conversations on Chemistry. Part One. (Ramsey.) i2mo, i 50 " " " " Part Two. (TumbtilL) i2mo, 2 00 * Palmer's Practical Test Book of Chemistry l2mo, l 00 * PauU's Physical Chemistry in the Service of Medicine. (Fischer. ' ... - lamo, i 25 * Penfield's Notes on Determinative Mineralogy and Record of Mineral Tests. Svo, paper, 50 Pictet's The Alkaloids and their Chemical Constitution. (Biddle.) Svo, 5 00 Pinner's Introduction to Organic Chemistry. (Austen.) i2mo, i 50 Poole's Calorific Power of Fuels Svo, 3 00 Prescott and Winslow's Elements of Water Bacteriology, with Special Refer- ence to Sanitary Water Analysis i2nio, i 25 * Reisig's Guide to Piece-dyeing Svo, 25 00 Richards and Woodman's Air, Water, and Food from a Sanitary Standpoint.. Svo, 2 00 Ricketts and Miller's Notes on Assaying Svo, 3 00 Rideal's Sewage and the Bacterial Purification of Sewage .Svo, 4 00 Disinfection and the Preservation of Food Svo, 4 00 Riggs's Elementary Manual for the Chemical Laboratory Svo, i 25 Robine and Lenglen's Cyanide Industry. (Le Clerc.) Svo, 4 00 5 Ruddiman's Incompatibilities in Prescriptions 8vo, * Whys in Pharmacy i2mo, Sabin's Industrial and Artistic Technology of Paints and Varnish , . .8voi Salkowski's Physiological and Pathological Chemistry. (Orndorff.). .. . . .8vo, Schimpf 's Text-book of Volumetric Analysis i2ino. Essentials of Volumetric Analysis. lamo, * Qualitative Chemical Analysis 8vo, Smith's Lecture Notes on Chemistry for Dental Students 8vo, Spencer's Handbook for Chemists of Beet-sugar Houses i6mo, morocco Handbook for Cane Sugar Manufacturers i6mo, morocco, Stockbridge's Rocks and Soils 8vo, * Tillman's Elementary Lessons in Heat 8vo, * Descriptive General Chemistry 8voi Treadwell's Qualitative Analysis. (Hall.) • 8vOr Quantitative Analysis. (Hall.) 8vo, Turneaure and Russell's PubUc Water-supplies 8vo, Van Deventer's Physical Chemistry for Beginners. (Boltwood.) i2mo, * Walke's Lectures on Explosives 8vo, Ware's Beet-sugar Manufacture and Refining. VoL I Small 8vo, Vol. II SmallSvo, Washington's Manual of the Chemical Analysis of Rocks 8vo, Weaver's Military Explosives - 8vo, Wehrenfennig's Analysis and Softening of Boiler Feed-Water Bvo, Wells's Laboratory Guide in«Qualitative Chemical Analysis 8vo, Short Course in Inorganic Qualitative Chemical Analysis for Engineering Students i2mo. Text-book of Chemical Arithmetic ; i2mo, Whipple's Microscopy of Drinking-water 8vo, Wilson's Cyanide Processes i2mo, Chlorination Process. , i2rno, V/inton's Microscopy of Vegetable Foods 8vo, WuUing's Elementary Course in Inor^auic, Pharmaceutical, and Medical Chemistry i2mo. CIVIL ENGINEERING. BRIDGES AND ROOFS. HYDRAULICS. MATERIALS OF ENGINEERING RAILWAY ENGINEERING. Baker's Engineers' Surveying Instruments i2mo, 3 oa Bixby's Graphical Computing Table Paper igj X24i inches. 25 Breed and Hosmer's Principles and Practice of Surveying 8vo, 3 00 * Burr's Ancient and Modern Engineering and the Isthmian Canal 8vo, 3 50 Comstock's Field Astronomy for Engineers 8vo, 2 50 * CortheU's AUov7able Pressures on Deep Foundations l2mo, i 25 Crandall's Text-book on Geodesy and Least Squares 8vo, 3 00 Davis's Elevation and Stadia Tables 8vo, i 00 ElHott's Engineering for Land Drainage i2mo, i 50 Practical Farm Drainage i2mo, i 00 *Fiebeger's Treatise on Civil Engineering 8vo, 5 00 Flemer's Phototopographic Methods and Instruments 8vo, 5 00 Folwell's Sewerage. (Designing and Maintenance.) 8vo, 3 00 Freitag's Architectural Engineering. 2d Edition, Rewritten 8vo, 3 50 French and Ives's Stereotomy 8vo, 2 50 Goodhue's Municipal Improvements i2mo, i 50 Gore's Elements of Geodesy 8vo, 2 50 * Hauch and Rice's Tables of Quantities for Preliminary Estimates, l2mo, i 25 Hayford's Text-book of Geodetic Astronomy 8vo, 3 00 6 2 50 I 25 I 25 2 50 3 00 3 00 2 50 I 50 3 00 3 00 4 00 5 00 1 50 4 00 4 00 5 CO 2 00 3 00 A 00 i 50 50 25 50 50 5C 50 Bering's Ready Reference Tables (Conversion Factors) i6mo, morocco, Howe's Retaining Walls for Earth i2mo, Hoyt and Grover's River Discharge 8vo, * Ives's Adjustments of the Engineer's Transit and Level i6mo, Bds. Ives and Hilts's Problems in Surveying i6mo, morocco, Johnson's (J. B. ) Theory and Practice of Surveying Small 8vo, Johnson's (L. J.) Statics by Algebraic and Graphic Methods 8vo, Laplace's Philosophical Essay on Probabilities. (Truscott and Emory.) . i2mo, Mahan's Treatise on Civil Engineering. (1873.J (Wood.) 8vo, * Descriptive Geometry 8vo, Merriman's Elements of Precise Surveying and Geodesy. 8vo, Merriman and Brooks's Handbook for Surveyors i6mo, morocco, Nugent's Plane Surveying 8vo, Ogden's Sewer Design. . l2mo, Parsons's Disposal of Municipal Refuse. ^ 8vo, Patton's Treatise on Civil Engineering 8vo half leather. Reed's Topographical Drawing and Sketching 4to, Rideal's Sewage and the Bacterial Purification of Sewage 8vo, Riemer's Shaft-sinking under Difficult Conditions. (Coming and Peele.) . .8vo, Siebert and Biggin's Modern Stone-cuttmg and Masonry 8vo, Smith's Manual of Topographical Drawing. 'McMillan.) 8vo, Sondericker's Graphic Statics, with Applications to Trusses, Beams, and Arches. 8vo, Taylor and Thompson's Treatise on Concrete, Plain and Reinforced 8vo, Tracy's Plane Surveying i6mo, morocco, * Trautwine's Civil Engineer's Pocket-book i6mo, morocco, Venable's Garbage Crematories in America 8vo, Wait's Engineering and Architectural Jurisprudence 8vo, Sheep, Law of Operations Preliminary to Construction in Engineering and Archi- tecture 8vo, Sheep, Law of Contracts. 8vo, Warren's Stereotomy — Problems in Stone-cutting 8vo, 2 50 Webb's Problems in the Use and Adjustment of Engineering Instruments. i6mo, morocco, i 23 Wilson's Topographic Surveying 8vo, 3 50 BRIDGES AND ROOFS. BoUer's Practical Treatise on the Construction of Iron Highway Bridges. .8vo, 2 00 Burr and Falk's Influence Lines for Bridge and Roof Computations 8vo, 3 00 Design and Construction of MetaUic Bridges 8vo, 5 00 Du Bois's Mechanics of Engineering. VoL U Small 4to, 10 co Foster's Treatise on Wooden Trestle Bridges 4to, 5 00 Fowler's Ordinary Foundations 8vo, 3 50 Greene's Roof Trusses 8vo, 1 25 Bridge Trusses 8vo, 2 50 Arches in Wood, Iron, and Stone Svo^ 2 50 (G rimm 's Secondary Stresses in Bridge Trusses. (In Press.) Howe's Treatise on Arches 8vo, 4 00 Design of Simple Roof-trusses in Wood and SteeL 8vo, 2 00 Symmetrical Masonry Arches 8vo, 2 50 Johnson, Bryan, and Turneaure's Theory and Practice in the Designing of Modem Framed Structures Small 4to, 10 00 Merriman and Jacoby's Text-book on Roofs and Bridges; Part I. Stresses in Simple Trusses 8vo, 2 50 Part n. Graphic Statics 8vo, 2 50 Part in. Bridge Design . 8vo, 2 50 Part TV. Higher Structures Bvo, 2 50 7 7 50 5 00 4 00 3 00 1 50 2 50 2 00 5 00 3 00 5 00 2 00 6 00 6 50 5 00 5 50 3 00 Morison's Memphis Bridge. 4to, lo oo Waddell's De Pontibus, a Pocket-book for Bridge Engineers . . i6mo, morocco, 2 00 * Specifications for Steel Bridges i2mo, 50 Wright's Designing of Draw-spans, Two parts in one volume 8vo, 3 50 HYDRAULICS. Barnes's Ice Formation 8vo, 3 00 Bazin's Experiments upon the Contraction of the Liquid Vein Issuing from an Orifice. (Trautwine.) 8vo, 2 00 Bovey's Treatise on Hydraulics 8vo, 5 00 Chxirch's Mechanics of Engineering 8vo, 6 00 Diagrams of Mean Velocity of Water in Open Channels paper, i 50 Hydraulic Motors 8vo, 2 00 Coffin's Graphical Solution of Hydraulic Problems i6mo, morocco, 2 50 Flather's Dynamometers, and the Measurement of Power i2mo, 3 00 Folwell's Water-supply Engineering 8vo, 4 00 Frizell's Water-power 8vo, 5 00 Fuertes's Water and Public Health i2mo. 1 50 Water-filtration Works i2mo. 2 50 GanguiUet and Kutter's General Formula for the Uniform Flow of Water m Rivers and Other Channels. (Hering and Trautwine.) 8vo, 4 00 Hazen's Clean Water and How to Get It Large l2mo, 1 5o Filtration of Public Water-supply 8vo, 3 00 Hazlehurst's Towers and Tanks for Water- works 8vo, 2 50 Herschel's 115 Experiments on the Carrying Capacity of Large, Riveted, Metal Conduits 8vo, 2 00 * Hubbard and Kiersted's Water-works Management and Maintenance. . . 8vo, 4 co Mason's Water-supply. (Considered Principally from a Sanitary Standpoint.) 8vo, 4 00 Merriman's Treatise on Hydraulics. . 8vo, 5 00 * Michie's Elements of Analytical Mechanics 8vo, 4 00 Schuyler's Reservoirs for Irrigation, Water-power, and Domestic Water- supply Large 8vo, 5 00 * Thomas and Watt's Improvement of Rivers 4to, 6 00 Tumeaure and Russell's Public Water-supplies 8vo, 5 00 Wegmann's Design and Construction of Dams. 5th Edition, enlarged. . .4to, 6 00 Water-supply of the City of New York from 1658 to 1895 4to, 10 00 Whipple's Value of Pure Water Large i2mo, i 00 Williams and Hazen's Hydraulic Tables 8vo, i 50 Wilson's Irrigation Engineering Small 8vo, 4 00 Wolff's Windmill as a Prime Mover 8vo, 3 00 Wood's Turbines Bvo, 2 50 Elements of Analytical Mechanics 8vo, 3 00 MATERIALS OF ENGINEERING. Baker's Treatise on Masonry Construction 8vo, 5 00 Roads and Pavements 8vo, 5 00 Black's United States Public Works Oblong 4to, 5 00 * Bovey's Strength of Materials and Theory of Structures 8vo, 7 50 Burr's Elasticity and Resistance of the Materials of Engineering 8vo, 7 50 Byrne's Highway Construction 8vo, 5 00 Inspection of the Materials and Workmanship Employed in Construction. i6mo, 3 00 Church's Mechanics of Engineering 8vo, 6 00 Du Bois's Mechanics of Engineering. Vol. I Small 4to 7 50 *Eckers Cements, Limes, and Plasters 8vo, 6 00 Johnson's Materials of Construction. Large 8vo, 6 oo Fowler's Ordinary Foundations 8vo, 3 50 Graves's Forest Mensuration 8vo, 4 00 * Greene's Structural Mechanics 8vo, 2 50 Keep's Cast Iron. 8vo, 2 so Lanza's Applied Meclianics 8vo, 7 50 Martens's Handbook on Testing Materials. (Henning.) 2 vols 8vp, 7 50 Maurer's Technical Mechanics 8vo, 4 00 Merrill's Stones for Building and Decoration 8vo, 3 00 Merriman's Mechanics of Materials 8vo, 5 00 * Strength of Materials i2mo, ■ i 00 Metcalf's Steel. A 3Ianual for Steel-users i2mo, 2 00 Patton's Practical Treatise on Foundations 8v0) 5 00 Richardson's Modern Asphalt Pavements 8vo, 3 00 Richey's Handbook for Superintendents of Construction i6mo, mor., 4 00 * Ries's Clays: Their Occurrence. Properties, and Uses. 8vo, 5 00 Rockwell's Roads and Pavements in France i2mo, i 25 Sabin's Industrial and Artistic Technology of Paints ar-i Varnish 8vo, 3 00 ♦Schwarz's Long-ieaf Pine in Virgin Forest ., lamo. i 25 Smith's Materials of Machines i2mo, i 00 Snow's Principal Species of Wood 8vo, 3 50 Spalding's Hydraulic Cement i2ino, 2 00 Text-book on Roads and Pavements i2mo, 2 00 Taylor and Thompson's Treatise on Concrete, Plain and Reinforced 8vo, s 00 Thurston's Materials of Engineering. 3 Parts 8vo, 8 00 Part L Non-metaUic Materials of Engineering and Metallurgy 8vo, 2 00 Part n. Iron and SteeL 8vo, 3 50 Part m. A Treatise on Brasses, Bronzes, and Other Alloys and their Constituents 8vo , 250 TiUson's Street Pavements and Paving Materials. , 8vo, 4 00 Tuxneaure and J-Iaurer's Principles of Reinforced Concrete Constmction- Svo, 3 00 Waddell's De Pontibus. A Pocket-book for Bridge Engineers. . . i6mo. r::or., 2 00 * Specifications for Steel Bridges i2mo, 50 Wood's (De V.I Treatise on the Resistance of Materials, and an Appendix on the Preservation of Timber Svo, 2 00 Wood's CDe V. ) Elements of Analytical Mechanics 8vo, 3 00 Wood's (M. P. 1 Rustless Coatings: Corrosion and Electrolysis of Iron and SteeL 8vo, 4 00 RAILWAY ENGINEERING. Andrew's Handbook for Street Railway Engineers 3x5 inches, morocco, i 25 Berg's Buildings and Structures of American Railroads 4.to, 5 00 Brook's Handbook of Street Railroad Location i6nio, morocco, i 50 Butt's Civil Engineer's Field-book i6mo, morocco, 2 50 Crandall's Transition Ctirve i6mo, morocco, i 50 Railway and Other Earthwork Tables Svo, i 50 Crookel:t's Methods for Earthwork Ccmputatioris. (In Press. Dawson's "Engineering" and Electric Traction Pocket-book. i6mo. morocco 5 00 Dredge's History of the Pennsylvania Railroad: (1879" Paper, 5 00 Fisher's Table of Cubic Yards Cardboard, 23 Godwin's Railroad Engineers' Field-book and Explorers' Guide. . . i6mo, mor., 2 50 Hudson's Tables for Calculating the Cubic Contents of Excavations and Em- bankments 8vo, I 00 MoUtor and Beard's Manual for Resident Engineers i6mo, 1 00 Nagle's Field Manual for Railroad Engineers i6mo, morocco, 3 00 Philbrick's Field Manual for Engineers r6mo, morocco, 3 00 Raymond's Elements of Railroad Engineering. 'In Press.; Searles's Field Engineering i6mo, morocco, 3 00 Railroad Spiral i6nio, morocco, x 50 Taylor's Prismoidal Formulae and Earthwork 8vo, i 50 * Trautwine's Method of Calculating the Cube Contents of Excavations and Embankments by the Aid of Diagrams 8vo, 2 00 The Field Practice of Laying Out Circular Cvirves for Railroads. i2mo, morocco, 2 50 Cross-section Sheet Paper, 25 Webb's Railroad Construction , i6mo, morocco, 5 00 Economics of Railroad Construction Large i2mo, 2 50 Wellington's Economic Theory of the Location of Railways. ...... Small 8vo,, 5 00 DRAWING. Barr's Kinematics of Machinery Svo, 2 50 * Bartlett's Mechariical Drawing Svo, 3 00 * " " " Abridged Ed Svo, 1 so Coolidge's Manual of Drawing Svo, paper, i 00 Coolidge and Freeman's Elements of General Drafting for Mechanical Engi- neers Oblong 4t0) 2 so Durley's Kinematics of Machines Svo, 4 00 Emch's Introduction to Projective Geometry and its Applications.. ..... .Svo, 2 50 Hill's Text-book on Shades and Shadows, and Perspective Svo, 2 00 Jamison's Elements of Mechanical Drawing Svo, 2 50 Advanced Mechanical Drawing Svo, 2 00 Jones's Machine Design: Part I. Kinematics of Machinery. Svo, i 50 Part II. Form, Strength, and Proportions of Parts Svo, MacCord's Elements of Descriptive Geometry Svo, Kinematics; or. Practical Mechanism Svo, Mechanical Drawing 4to, Velocity Diagrams Svo, MacLeod's Descriptive Geometry Small Svo, * Mahan's Descriptive Geometry and Stone-cutting Svo, Industrial Drawing. (Thompson.) Svo, Moyer's Descriptive Geometry Svo, 2 00 Reed's Topographical Drawing and Sketching 4to, s 00 Reid's Course in Mechanical Drawing Svo, 2 00 Text-book of Mechanical Drawing and Elementary Machine Design. Svo, 3 00 Robinson's Principles of Mechanism Svo, 3 00 Schwamb and Merrill's Elements of Mechanism Svo, 3 00 Smith's (R. S.) Manual of Topographical Drawing. (McMillan.) Svo, 2 50 Smith (A. W.) and Marx's Machine Design. Svo, 3 00 * Titsworth's Elements of Mechanical Drawing Oblong Svo, i 25 Warren's Elements of Plane and Solid Free-hand Geometrical Drawing. i2mo, i 00 Drafting Instruments and Operations i2mo, 1 25 Manual of Elementary Projection Drawing i2mo, i 50 Manual of Elementary Problems in the Linear Perspective of Form and Shadow i2mo, i 00 Plane Problems in Elementary Geometry i2mo, 125 Elements of Descriptive Geometry, Shadows, and Perspective Svo, 3 50 General Problems of Shades and Shadows Svo, 3 00 Elements of Machine Construction and Drawing Svo, 7 50 Problems, Theorems, and Examples in Descriptive Geometry Svo, 2 50 Weisbach's Kinematics and Power of Transmission. (Hermann and Klein.) Svo, 5 Oq Whelpley's Practical Instruction in the Art of Letter Engraving i2mo, 2 oo Wilson's (H. M.) Topographic Surveying Svo, 3 50 10 3 00 3 00 5 00 4 00 I SO I 50 I 50 3 50 I 25 3 oo I 00 3 oo 3 oo 3 oo I so 2 oo 3 oo 1 25 S oo 2 50 4 00 3 CO 2 50 I 00 2 50 Wilson's (V. T.) 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Svo, Flather's Dynamometers, and the Measurement of Power i2mo, Gilbert's De Magnete. (Mottelay.) Svo, Hanchett's Alternating Currents Explained i2mo, Bering's Ready Reference Tables (Conversion Factors) lomo, morocco, Hobart and Ellis's High-speed Dynamo Electric Machinery. (In Press.) Holman's Precision of Measurements Svo, 2 00 Telescopic Mirror-scale Method, Adjustments, and Tests .... Large Svo, 75 Karapetoff's Experimental Electrical Engineering. (In Press.) Kinzbrunner's Testing of Continuous-current Machines Svo; 2 00 Landauer's Spectrum Analysis. (Tingle.) Svo, 3 00 Le Chatelier's High-temperature Measurements. (Boudouard — Burgess.) i2mo, 3 00 Lob's Electrochemistry of Organic Compounds. (Lorenz.) Svo, 3 00 * Lyons'3 Treatise on Electromagnetic Phenomena. Vols. I. and II. Svo, each, 6 00 * Michie's Elements of Wave Motion Relating to Sound and Light Svo, 4 00 Niaudet's Elementary Treatise on Electric Batteries. (Fishback.) i2mo, 2 50 Norris's Introduction to the Study of Electrical Engineering. (In Press.) * Parshall and Hobart's Electric Machine Design 4to, half morocco, 12 50 Reagan's Locomotives: Simple, Compound, and Electric. New Edition. Large 12 mo, 3 50 * Rosenberg's Electrical Engineering. (Haldane Gee — Kinzbrunner.). . .8vo, 2 00 Ryan, Norris, and Hoxie's Electrical Machinery. VoL I Svo, 2 50 Thurston's Stationary Steam-engines '. ■ ■ Svo, 2 50 * Tillman's Elementary Lessons in Heat Svo, i 50 Tory and Pitcher's Manual of Laboratory Physics Small Svo, 2 00 Ulke's Modern Electrolytic Copper Refining Svo, 3 00 LAW. * Davis's Elements of Law Svo, 2 50 * Treatise on the MiUtary Law of United States Svo, 7 00 * Sheep, 7 50 ■'' Dudley's Military Law and the Procedure ol Courts- martial ... Large i2mo, 2 50 Manual for Courts-martial i6mo, morocco, i 50 Wait's Engineering and Architectural Jurisprudence. ... 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Elementary Treatise on Differential Calculus Small 8vo, 3 Elementary Treatise on the Integral Calculus Small 8vo, i Johnson's W. W.,, Curve Tracing in Cartesian Co-ordinates i2mo, i Johnson's (W. W.) Treatise on Ordinary and Partial Differential Equations. Small 8to, 3 Johnson's Treatise on the Integral Calculus Small Svo, 3 Johnson's W. W.' Theory of Errors and the Method of Least Squares. i2mo, 1 * Johnson's W. W.,' Theoretical Mechanics i2mo, 3 Laplace's Philosophical Essay on Probabilities. (Tniscott and Emory., .i2mo, 2 * Ludlow and Bass. Elements of Trigonometry and Logarithmic and Other Tables Svo, 3 i Trigonometry and Tables published separately Each, 2 ' * Ludlow's Logarithmic and Trigonometric Tables Svo, i • Manning's IrrationaIN umbers and their Representation bySequences and Series i2mo, I Mathematical Monographs. Edited by Mansfield Merriman and Robert S. Woodvrard Octavo, each i No. 1. History of Modern Mathematics, by David Eugene Smith. Kg. 2. Synthetic Projective Geometry, by George Bruce Halsted. Ko. 3. Determi n ants, by Laenas Gift'ord "Weld. 'So. 4. Hyper- bolic Functions, by James McMahon. Ifo. 5. HarmorJc Func- tions, by William. E. Byerly. Uo. 6. Grassmann's Space Analysis, by Edward W. Hyde. 'So. 7. Probabihty and Theory of Errors, by Robert S. Woodward. Ko. 8. Vector Analysis and Quaternions, by Alexander Macfarlane. No. 9. Differential Equations, by William Woolsey Johnson. Ko. 10. The Solution of Eqiiations, by Mansfield Merriman. JTo. 11. Functions of a Complex Variable, by Thomas S. Fiske. Maurer's Technical Mechanics Svo, 4 < Merriman's Method of Least Squares Svo, 2 < Rice and Johnson's Elementary Treatise on the Differential Calcxilus. . Sm. Svo, 3 ( Differential and Integral Calculus. 2 vols, in one Small Svo, ■>. ; * Veblen and Lennes's Introduction to the Real Infinitesimal Analysis of One Variable Svo , 2 < Wood's Elements of Co-ordinate Geometry Svo, 2 ( Trigonometry: Analytical, Plane, and Spherical i2mo, i < mecha:s'ical e:s^gi:n"eerin&. ilATERIALS OF EXGIKEERIKG, STEAM-E^'GIKES AKD BOILERS. Bacon's Forge Practice i2mo, Baldwin's Steam Heating for Buildings i2mo, Barr's Kinematics of Machinery Svo, * Bartlett's Mechanical Drawing Svo, * '• " " Abridged Ed Svo, Benjamin's Wrinkles and Recipes i2mo, Carpenter's Experimental Engineering Svo, Heating and Ventilating Buildings Svo, Clerk's Gas and Oil Engine Small Svo, Coolidee's Manual of Drawing Svo, paper, Coolidge and Freeman's Elements of General Drafting for Mechanical En- gineers Oblong 4to , Cromwe'l's Treatise on Toothed Gearing i2ino. Treatise on Belts and Pullevs i2mo, 13 I 30 2 SO 2 50 3 00 1 50 2 GO 6 00 4 00 4 00 I 00 2 50 I 50 I 50 Durley's Kinematics of Machines 8vo, 4 00 Flather's Dynamometers and the Measurement of Power. i2mo, 3 00 Rope Driving i2mo, 2 00 Gill's Gas and Fuel Analysis for Engineers , i2mo, i 25 Hall's Car Lubrication i2mo, i 00 Bering's Ready Keference Tables (Conversion Factors) i6mo, morocco, 2 50 Button's The Gas Engine, 8vo, s 00 Jamison's Mechanical Drawing 8vo, 2 50 Jones's Machine Design: Part I. Kinematics of Machinery " 8vo, i 50 Part II. Form, Strength, and Proportions of Parts 8vo, 3 00 Kent's Mechanical Engineers' Pocket-book i6mo, morocco, 5 00 Kerr's Power and Power Transmission 8vo, 2 00 Leonard's Machine Shop, Tools, and Methods 8vo, 4 00 * Lorenz's Modern Refrigerating Machinery. (Pope, Haven, and Dean.) . . Svo, 4 00 MacCord's Kinematics; or. 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Svo, 5 00 Machinery of Transmission and Governors. (Herrmann — Klein.). .Svo, 5 00 Wolff's Windmill as a Prime Mover Svo, 3 00 Wood's Turbines Svo, 2 50 MATERIALS OF ENGINEERING. * Bovey's Strength of Materials and Theory of Structures Svo, 7 50 Burr's Elasticity and Resistance of the Materials of Engineering. 6th Edition. Reset Svo, 7 50 Church's Mechanics of Engineering Svo, 6 00 * Greene's Structural Mechanics Svo, 2 50 Johnson's Materials of Construction Svo, 6 00 Keep's Cast Iron Svo, 2 50 Lanza's Applied Mechanics Svo, 7 50 Martens's Handbook on Testing Materials. (Henning.) Svo, 7 50 Maurer's Technical Mechanics Svo, 4 00 Merriman's Mechanics of Materials Svo, 5 00 * Strength of Materials i2mo, 1 00 Metcalf's SteeL A Manual for Steel-users i2mo, 2 00 Sabin's Industrial and Artistic Technology of Paints and Varnish Svo, 3 00 Smith's Materials of Machines i2mo, i 00 Thurston's Materials of Engineering 3 vols., Svo, 8 00 Part II. Iron and Steel Svo, 3 50 Part in. A Treatise on Brasses, Bronzes, and Other Alloys and their Constituents Svo, 2 50 14 Wood's CDe V.) Treatise on the Resistance of Materials and an Appendix on the Preservation of Timber 8to, 2 00 Elements of Analj^'cal Mechanics 8vo, 3 00 Wood's CM. P.) Rustless Coatings: Corrosion and Electrolysis of Iron and Steel 8vo , 4 00 STEAM-ENGINES AND BOILERS. Berry's Temperature-entropy Diagram. i2mo, i 25 Camot's Reflections on the Motive Power of Heat. (Thurston.) i2mo, i 50 Creighton's Steam-engine and olher Heat-motors. . . Svo, 5 00 Dawson's "Engineering" and Electric Traction Pocket-book. , . .i6mo, mor., 5 00 Ford's Boiler Making for Boiler Makers iSmo, i 00 Goss's Locomotive Sparks Svo, 2 00 Locomotive Performance Svo, 5 00 Hemenway's Indicator Practice and Steam-engine Economy i2mo, 2 00 Button's Mechanical Engineering of Power Plants Svo, 5 00 Heat and Heat-engines Svo, 5 00 Kent's Steam boiler Economy Svo, 4 00 Kneass's Practice and Theory of the Injector Svo, i 50 MacCord's SUde-valves Svo, 2 00 Meyer's Modem Locomotive Construction 4to, 10 00 Peabody's Manual of the Steam-engine Indicator i2mo, i 50 Tables of the Properties of Saturated Steam and Other Vapors Svo, i 00 Thermodynamics of the Stsam-engine and Other Heat-engines Svo, 5 00 Valve-gears for Steam-engines Svo, 2 50 Peabody and Miller's Steam-boiiers Svo, 4 00 Pray's Twenty Years vrith the Indicator Large Svo, 2 50 Pupin's Thermodynamics of Reversible Cycles in Gases and Saturated Vapors. (Osterberg. ' i2nio, i 25 Reagan's Locomotives: Simple, Compound, and Electric. New Edition. Large i2mo, 3 50 Sinclair's Locomotive Engine Running and Management i2nio, 2 00 Smart's Handbook of Engineering Laboratory Practice i2mo, 2 50 Snow's Steam-boiler Practice Svo, 3 00 Spangler's Valve-gears Svo, 2 50 Notes on Thermodynamics i2mo, i 00 Spangler, Greene, and Marshall's Elements of Steam-engineering Svo, 3 00 Thomas's Steam-turbines Svo, 3 50 Thurston's Handy Tables Svo, i 50 Manual of the Steam-engine 2 vols., Svo, 10 00 Part I. History, Structure, and Theory. Svo, 6 00 Part n. Design, Construction, and Operation Svo, 6 00 Handbook of Engine and Boiler Trials, and the Use of the Indicator and the Prony Brake Svo, 5 00 Stationary Steam-engines Svo, 2 50 Steam-boiler Explosions in Theory and in Practice i2mo, i 50 Manual of Steam-boilers, their Designs, Construction, and Operation -Svo, 5 00 Wehrenfenning's Analysis and Softening of Boiler Feed-water 'Patterson) Svo, 4 00 Weisbach's Heat, Steam, and Steam-engines. ^Du Bois.j Svo, 5 00 Whitham's Steam-engine Design Svo, 5 00 Wood's Thermodynamics, Heat Motors, and Refrigerating Machines. . .Svo, 4 00 MECHANICS AND MACHINERY. Bart's Kinematics of Machinery 870, 2 50 * Bovey's Strength of Materials and Theory of Structures Svo, 7 50 Chase's The Art of Pattern-making i2mo, 2 50 15 Church's Mechanics of Engineering 8vo, 6 oo Notes and Examples in Mechanics 8vo, 2 00 Compton's First Lessons in Metal-working lamo, 1 50 Compton and De Groodt's The Speed Lathe lamo, i so Cromwell's Treatise on Toothed Gearing i2mo, i 50 Treatise on Belts and Pulleys i2mo, i 50 Dana's Text-book of Elementary Mechanics for Colleges and Schools. .i2mo, i 50 Dingey's Machinery Pattern Making i2mo, 2 00 Dredge's Record of the Transportation Exhibits Building of the World's Columbian Exposition of 1893 4to half morocco, 5 00 Du Bois's Elementary Principles of Mechanics : Vol. I. Kinematics 8vo, 3 50 VoL II. Statics 8vo, 4 00 Mechanics of Engineering. Vol. I Small 4to, 7 50 Vol. n Small 4to, 10 00 Durley's Kinematics of Machines 8vo, 4 00 Fitzgerald's Boston Machinist i6mo, i 00 Flather's Dynamometers, and the Measurement of Power i2mo, 3 00 Rope Driving i2mo, 2 00 Goss's Locomotive Sparks 8vo, 2 00 Locomotive Performance 8vo, 5 00 * Greene's Structural Mechanics 8vo, 2 50 Hall's Car Lubrication i2mo, i 00 Hobart and Ellis's High-speed Dynamo Electric Machinery. (In Press.) HoUy's Art of Saw Filinj; iSmo, 75 James's Kinematics of a Point and the Rational Mechanics of a Particle. Small Svo, 2 00 * Johnson's (W. W.) Theoretical Mechanics i2mo, 3 00 Johnson's (L. J.) Statics by Graphic and Algebraic Methods Svo, 2 00 Jones's Machine Design: Part I. Kinematics of Machinery Svo, i 50 Part II. Form, Strength, and Proportions of Parts Svo, 3 00 Kerr's Power and Power Transmission Svo, 2 00 Lanza's Applied Mechanics Svo, 7 50 Leonard's Machine Shop, Tools, and Methods Svo, 4 00 * Lorenz's Modern Refrigerating Machinery. (Pope, Haven, and Dean.). Svo, 4 00 MacCord's Kinematics; or. Practical Mechanism Svo, 5 00 Velocity Diagrams Svo, 1 50 * Martin's Text Book on Mechanics, Vol. I, Statics i2mo, i 25 * Vol. 2, Kinematics and Kinetics . .l2mo, 1 50 Maurer's Technical Mechanics Svo, 4 00 Merriman's Mechanics of Materials Svo, 5 00 * Elements of Mechanics i2mo, i 00 * Michie's Elements of Analytical Mechanics Svo, 4 00 * Parshall and Hobart's Electric Machine Design 4to, half morocco, 12 50 Reagan's Locomotives : Simple, Compound, and Electric. New Edition. Large i2mo, 3 5o Reid's Course in Mechanical Drawing Svo, 2 00 Text-book of Mechanical Drawing and Elementary Machine Design. Svo, 3 00 Richards's Compressed Air i2mo, i 50 Robinson's Principles of Mechanism Svo, 3 00 Ryan, Norris, and Hoxie's Electrical Machinery. Vol. I Svo, 2 50 Sanborn's Mechanics : Problems Large i2mo, i 50 Schwamb and Merrill's Elements of Mechanism Svo, 3 00 Sinclair's Locomotive-engine Running and Management i2mo, 2 00 Smith's (O.) Press-working of Metals Svo, 3 00 Smith's (A. W.) Materials of Machines i2mo, i 00 Smith (A. W.) and Marx's Machine Design , Svo, 3 00 Sorel's Carbureting and Combustion of Alcohol Engines. (Woodward and Preston.) Large Svo, 3 o« 16 Spangler, Greene, and Marshall's Elements of Steam-engineering 8vo. 3 00 Thurston's Treatise on Friction and Lost Work in Machinery and Mill Work 8,,o^ 3 00 Animal as a Machine and Prime Motor, and the Laws of Energetics. i2mo, i 00 Tillson's Complete Automobile Instructor i6mo SO Morocco, 2 00 Warren's Elements of Machine Construction and Drawin^ 8vo, 7 50 Weisbach's Kinematics and Power of Transmission. (Herrmann — Klein. ).8vo. 5 00 Machinery of Transmission and Governors. (Herrmann— Klein.) .8vo. 5 00 Wood's Elements of Analytical Mechanics ovo, 3 00 Principles of Elementary Mechanics i2mo, i 25 Turbines 8^o| 2 50 The World's Columbian Exposition of 1893 4to i 00 MEDICAL. * Bolduan's Immune Sera l2mo, 1 50 De Fursac's Manual of Psychiatry. (Rosanoff and Collins. ). .. Large i2mo'. 250 Ehrlich's Collected Studies on Immunity. (Bolduan.) 8vo, 6 00 * Fischer's Physiology of Ahmentatioii Large l2mo, cloth,' 2 00 Hammarsten's Text-book on Physiological Chemistry. (Mandel.) 8vo, 4 00 Lassar-Cohn's Practical Urinary Analysis. (Lorenz.). i2n:o,' r 00 * Pauli's Physical Chemistry m the Service of Medicine. (Fischer. ) . . . . i2mo, i 25 * Pozzi-Escot's The Toxins and Venoms and their Antibodies. (Cohn. 1. i2mo, i 00 Rostoski's Serum Diagnosis. (Bolduan.) i2mo', i 00 Salkowski's Physiological and Pathological Chemistry. (Orndorff.) 8vo', 2 50 * Satterlee's Outlines of Human Embryology i2mo, 1 25 Steel's Treatise on the Diseases of the Dog gvo, 3 50 Von Behring's Suppression of Tuberculosis. (Bolduan.) i2mo, i 00 Woodhull's Notes on Mihtary Hygiene i6mo, r 50 * Personal Hygiene " ,2jno| ^ ^^ Wulling's An Elementary Course in Inorganic Pharmaceutical and Medical Chemistry . i2mo, 2 00 METALLURGY. Betts's Lead Reflning by Electrolysis. (In Press.) Egleston's Metallurgy of Silver, Gold, and Mercury ■ V°l- I- Silver 8vo, 750 Vol. II. Gold and Mercixry g^^^ ^ 2^ Goesel's Minerals and Metals: A Reference Book - . .'. . i6mo^ mor' 3 00 * Iles's Lead-smelting \^^^^ ^ ^^ Keep's Cast Iron g^^^ ^ 50 Kunhardt's Practice of Ore Dressing in Europe 8vo, i ro Le Chateher's High-temperature Measurements. (Boudouard— Burgess.)i2mo,' 3 00 Metcalf's Steel. A Manual for Steel-users. . . i2mo' 2 00 MiUer-s Cyanide Process ■.■.■;■■■.■ ,^^^[ ^ „„ Minet's Production of Aluminum and its Industrial Use. (Waldo.). . . . ramo. 2 50 Robine and Lenglen's Cyanide Industry. (Le Clerc). ..... gvo' Smith's Materials of Machines ™, . , -. . i2mo, I 00 Thurston s Materials of Engineering. In Three Parts. «vn a »„ Part n. Iron and Steel .'...'.'.' gH' I Part m. A Treatise on Brasses, Bronzes, and Other Alloys and their Constituents „ Ulke's Modern Electrolytic Copper Refining ................... ' sTo, 3 00 MINERALOGY. Barringer's Description of Minerals of Commercial Value. Oblong, morocco 2 =^0 Boyd s Resources of Southwest Virginia o ' ovo, 3 00 17 4 oo 5 oo 50 1 oa I 25 5 oo Boyd's Map of Southwest Virignia Pocket-book form. 2 oo ♦Browning's Introduction to the Rarer Elements 8vo, i 50 Brush's Manual of Determinative Mineralogy. (Penfield. ) 8vo, 4 00 Chester's Catalogue of Minerals. 8vo, paper, i 00 Cloth, I 25 Dictionary of the Names of Minerals 8vo, 3 50 Dana's System of Mineralogy Large 8vo, half leather, 12 50 First Appendix to Dana's New " System of Mineralogy." 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