Infection and immunity

Front matter

NRLF

B M 210 3DD

MEDICAL

Foreword

The development of modern medicine, its influence on civilization, and its role in the advancement of the welfare of the nation are matters which concern us all. While our lives are short and we are soon to pass away, our children and their descendants will possess and occupy the land, — at least we hope that this may be true. No nation can be great so long as disease prevails widely among any classes. Modern medicine has become largely a social service. Preventive medicine is the keystone of the triumphal arch of modern civilization. Displace it and the whole structure will fall. Widespread epidemics lead to national decay. Infection has overthrown nations and has blotted out civilizations in the past. We are aware of the fact that the future of this country does not depend wholly on the medical man, but he should be ready at all times to do his part in assisting in the progress of the nation. Medicine consists of those facts, gathered from the various sciences, which can be utilized in the prevention or cure of disease. That nation which does not encourage scientific investigation, must fall into the rear. It is, therefore, the duty of the state to favor research medicine. Every physician who treats an infectious disease renders a service to the individual under his treatment, and at the same time he renders a greater service to the community in preventing the spread of the disease.

The present volume is an incomplete and imperfect statement of what medicine has done, is doing, and an indication of what it may do for the common good. The attempt has been made to present these facts in non-technical verbiage so that any intelligent citizen may read, comprehend, and appreciate them. The medical profession feels that it has a patriotic duty to perform in the advancement of the best interests of the people. It offers its services, and begs an intelligent appreciation of what it has done, is doing, and may do.

Contents

Infection 17

Historical Introduction 19

Asiatic Cholera 57

Introduction

The purpose of this writing is to state the essential facts of infection and immunity accurately and simply, so that they may be understood by the intelligent, non-professional man. The reduction and ultimate eradication of unnecessary disease and the consequent prolongation of life with improved health constitute a patriotic obligation which every citizen should strive to appreciate and to do his part in its performance.

The further developments of medicine, both curative and preventive, depend on scientific investigations. The public is the beneficiary and should in every way encourage medical research. By the application of discoveries already made, the burden of disease has been lightened, sickness has become less frequent and less prolonged, a greater degree of health has been secured, the efficiency of the individual and of the nation has been increased, and life has been lengthened and made more enjoyable. The Federal government and the states should sustain and promote scientific research. That government is the best which secures for its citizens the greatest freedom from disease, the highest degree of health and the longest life, and that people which most fully secures the enjoyment of these blessings will dominate the world.

Medicine consists of the application of scientific discovery to the prevention and cure of disease. All else which may go under the name of medicine is sham and fraud. Without advancement in the physical, chemical, and biologic sciences, there can be no progressive movement in medicine. Scientific knowledge is gained only by observation and experiment. Before the time of Jenner, we are told by the historian, it was unusual to meet in London one whose face was not marked by smallpox. There was a popular belief that one who had cowpox was immune to smallpox. Jenner put this belief to a scientific test. The result was the discovery of vaccination, and this secured the abolition of this disfigurement and a marked reduction in mortality. In 1849, a village doctor, with a crude microscope, studied the blood of animals sick with anthrax and compared it with that of healthy ones. He discovered the anthrax bacillus. This work was extended by Davaine, Pasteur, Koch, and others, and from this, the science of bacteriology has been developed. The particulate causes of many infectious diseases have been recognized, isolated, and their effects on animals demonstrated. Many of the mysteries of contagion have been revealed and the conditions of the transmission of disease made known. The fundamental principles of preventive medicine have been developed into a science which is to-day the most potent factor in the progress of civilization. Finlay suspected a certain mosquito to be the carrier of the virus of yellow fever. Reed and his co-workers demonstrated the truth of this theory, the work of Gorgas has freed Havana from the pestilence, and the construction of the Panama Canal is an accomplished fact.

Laveran discovered Plasmodium malariae. Ross studied its life history, and the fetters of a disease that has so long retarded the progress of man, have been broken. Mitchell and Reichert investigated the poisonous properties of snake venom. Sewall immunized animals with it. Ehrlich studied the similar bodies, abrin, ricin and diphtheria toxin, and von Behring and Roux gave the world antitoxin, the magical curative value of which has greatly reduced the mortality from diphtheria. The experiments of Villemin demonstrated the contagious nature of tuberculosis, long suspected and frequently denied. The diligent research of Koch resulted in the recognition and isolation of the causative agent, and since this discovery the mortality of the Great White Plague in Europe and the United States has been diminished more than half. It is, then, within the range of sanity to look forward to the time when the former "Captain of the hosts of death" will be known only by the fearful records he once made in the history of man's struggle to be relieved from the heavy tribute paid to infection.

We boast of a great civilization, but this is justified only within limits. Science more nearly dominates the world than at any time in the past. Learning permeates the masses more deeply, but credulity and ignorance are widely prevalent. In this country of nearly one hundred millions, there are thousands whose greed impedes the progress of the whole, tens of thousands whose ignorance retards their own growth, and other thousands who live by crime and procreate their kind to feed on generations to come. We have our schools, colleges, and universities, while our almshouses, insane asylums, and penal institutions are full. In our cities we see the palatial homes of the very rich, the splendid temples of trade and commerce, the slums of want and poverty, and the homes, both rich and squalid, of vice and crime. No nation in this condition can be given a clean bill of health. Our hilltops are illuminated by the light of knowledge, but our valleys are covered by the clouds of ignorance. We have not emerged from the shadows of the dark ages. The historian of the future will have no difficulty in convincing his readers that those who lived at the beginning of the twentieth century were but slightly removed from barbarism, as he will tell that the school, saloon, and house of prostitution flourished in close proximity; that the capitalist worked his employees under conditions which precluded soundness of body; that the labor union man dynamited buildings; that while we sent missionaries to convert the Moslem and the Buddhist, ten thousand murders were committed annually in the midst of us, and that a large percentage of our mortality was due to preventable disease. Evidently there is much to be done before we pass out from the shadows of ignorance into the full light of knowledge. In this great work for the betterment of the race the medical profession has important duties to perform. I do not mean to imply that the uplift of mankind devolves wholly on the medical man. The burdens are too many and too diversified, the ascent is too steep and the pathways are too rough for one profession to hope to reach unaided the high plateau we seek. Moreover, other callings have no right, and should have no desire to shirk the moral responsibilities which rest alike on all. But in past ages, medical men have been the chief torch bearers of science, whose light is the only one in which man may safely walk, and we must keep and transmit this trust and honor to those who follow us. I know of no scientific discovery, from the ignition of wood by friction to the demonstration of the causes of infection and the restriction of disease, which has not sooner or later assisted in the betterment of the race. It may be added that nothing else has so aided man in his slow and halting progress from the pestilential marshes of ignorance to the open uplands of intelligence.

In so great a work as the eradication of preventable disease, all intelligent people must cooperate. The law must support by proper enactments, and these must be enforced with justice and intelligence; it must recognize that the right to enjoy health is quite as sacred as that to possess property; that to poison men in factories and mines, to pollute drinking-water supplies, to adulterate foods, and to drug with nostrums, is manslaughter. Religion must teach the sanctity of the body as well as that of the soul, that ignorance is sin and knowledge virtue, that parenthood is the holiest function performed by man, and that to transmit disease is an unpardonable sin. The teacher must know hygiene as well as mathematics. The capitalist must recognize that improvement in health and growth in intelligence increase the efficiency of labor. There never has been a time when scientific medicine has had so many and such efficient and appreciative helpers as it has to-day. Our sanitary laws are for the most part good, but their administration is weak, on account of ignorance. The pulpits of the land are open, for the most part, to the sanitarian. The respectable newspapers are most effective in the crusade against quackery and disease. The philanthropist has learned that the advancement of science confers the greatest and most lasting benefits on man.

There is a moral obligation to be intelligent. Ignorance is a vice and when it results in injury to anyone, it becomes a crime, a moral, if not a statutory one. To infect another with disease, either directly or indirectly, as a result of ignorance, is an immoral act. The purpose of government is to protect its citizens, and a government which fails to shelter its citizens against infection is neither intelligent nor moral. To transmit disease of body or mind to offspring is an unpardonable sin. In a reasonable sense it is worse than murder, because it projects suffering into the future indefinitely.

That medicine has become a fundamental social service must be evident. To return one incapacitated by illness or injury to the condition of self-support, benefits not only the individual, but the community, inasmuch as it increases its productive capacity. Infirmity is a direct burden on the individual and scarcely less direct on the community. Weakness in any part diminishes the strength of the whole. It is a fully established principle in social economy that widespread intelligence and growth in knowledge are beneficial to the' state. It was in full recognition of this that the framers of the ordinance of 1787 wrote into that immortal document: "Religion, morality and knowledge being necessary to good government and the happiness of mankind, schools and the means of education shall forever be encouraged." The territory of the Northwest, the government of which was created in this ordinance, was at that time a vast waste of forest and prairie, furnishing a scant and precarious subsistence for savage tribes and attracting to its borders a few of the most hardy sons of civilization. The knowledge, for whose growth and diffusion the wise provision was made, has drained the malarial marshes, converted wild prairie and tangled wood into fruitful orchards and fertile fields, dotted the whole area with neat villages, reared great cities, linked all parts with steam and electric roads, and provided comfortable homes and abundant food for millions. The men who wrote the ordinance of 1787 left a great inheritance which is temporarily in our possession. Let us write into this great document: "Every ill which can be relieved shall be removed, and every preventable disease shall be prevented." The wisdom of our fathers has secured for us a greater measure of health and a longer term of life; let us do as well for those who are to possess this fair land in the next generation. Let us live not only for ourselves and the present, but for the greater and more intelligent life of the future.

Not myself, but the truth that in life I have spoken, Not myself, but the seed that in life I have sown Shall pass into ages — all about me forgotten Save the truth I have spoken, the things I have done.

All things are relative and health is no exception. With a greater degree of health among all, religion will become more effective for good, morality will have a deeper significance and a wider application, and knowledge will multiply and distribute its blessings more widely.

After the last epidemic of the plague in London, in 1665, the death-rate, so far as it can be ascertained, fell to between seventy and eighty per 1,000. During the next century it fell as low as fifty, but fluctuated greatly with recurring epidemics of typhus and smallpox. In the nineteenth, it gradually and quite constantly decreased and is now about fourteeen. In 1879-80, the first year in which the mortality

INTRODUCTION statistics of the United States possess sufficient accuracy to be of any value, the death-rate in the registered area was 19.8; in 1912 it was 13.9 — a decrease of 30 per cent. During the same time the mortality from typhoid fever has decreased 50 per cent. ; that from scarlet fever 89 per cent. ; that from diphtheria 84 per cent. ; that from tuberculosis 54 per cent. Hoffman states that had the death-rate for tuberculosis in 1901 continued, there would have been 200,000 more deaths from this cause from that date to" 1911 than actually did occur, so that the actual saving of lives from death by tuberculosis accomplished in that decennium averaged 20,000 a year. Preventive medicine measures its successes by the number of lives saved, and 20,000 a year preserved from death from one disease is no small triumph. In the last century the average of human life has been increased fifteen years and this increase could be duplicated in the next twenty years if the facts we now possess were effectively employed. Hoffman further states that the addition to the material wealth of this country secured by the reduction of deaths from tuberculosis within ten years amounts approximately to 6,200,000 years of human life, covering its most productive period. Medicine discovered the facts which have made this great work possible and has directed their application. With evidence of this kind before them, will our lawmakers listen to those who demand recognition as practitioners of medicine without proper qualifications ? The following figures give the death-rates from all causes and from each of certain infectious diseases in the registered area of the United States since the census of the year of 1879-80 :

.L-'CciLllO pCI

Year

Scarlet fever all causes

(all forms)

1879-80

19.8

54.0

34.0

112.6

326.2

1889-90

19.6

13.6

46.3

97.8

267.4

17.8

11.6

33.8

45.2

205.2

17.6

10.2

35.9

43.3

201.9

16.5

13.1

32.3

34.0

196.9

15.9

12.6

34.3

30.8

184.5

16.0

12.2

34.1

31.7

188.5

16.5

10.8

31.7

28.3

200.7

16.0

6.7

27.8

23.6

192.3

15.7

7.7

31.3

25.7

180.2

16.0

10.0

29.5

23.6

178.5

14.8

11.9

24.3

21.5

167.6

14.4

11.4

21.1

20.4

160.8

15.0

11.6

23.5

21.4

160.3

14.2

8.8

21.0

18.9

158.9

13.9

6.7

16.5

18.2

149.5

14.1

8.7

17.9

18.8

147.6

Preventive medicine, still in its youth, has accomplished great things. As I have stated, within the past thirty years in this country the mortality from tuberculosis has been reduced more than half, and with scarlet fever and diphtheria, the results have been more striking. Within the past ten years, the average life has been increased four years. Great epidemics which once devasted continents are no longer known in the more intelligent parts of the world. In fact, it may be said that the death-rate is now an excellent measure of intelligence. In 1911 the death-rate in London was 15 per thousand, while that of Moscow was 27.3. Preventive medicine is the keystone of the triumphal arch of modern civilization and its displacement would precipitate mankind into relative barbarism. Should the health administrators of any great commercial center fail, for even a few months, to exercise the function of restricting disease, the history of the epidemics of the middle ages might be repeated. Great things have been done, but greater tasks lie before us, and their accomplishment depends on the scientific wisdom of the medical profession and the intelligence of the people. Without the harmonious adjustment of these forces the greatest efficiency cannot be secured. While the mortality from tuberculosis has been reduced half in the past thirty-five years, we must not assume that the total eradication of this disease will be accomplished in the same number of years. Only the more progressive members of the profession have taken the initiative, and only the more intelligent members of the community have responded. Intelligence and the sense of moral responsibility must grow as the work proceeds. It remains for all who have the welfare of the race at heart to plan wisely and carry fonvard courageously the campaign against greed, ignorance and disease.

Chapter II Historical Introduction

The oldest and most persistent belief holds that disease is an infliction imposed on man by some supernatural power. This doctrine was handed down by tradition to the earliest civilizations, was incorporated in their records and is held by many to-day. Some have attributed disease to evil spirits and others have regarded it as a dispensation of their gods. The Babylonians regarded disease "as the work of demons which swarmed in the earth, air and water, and against which long litanies and incantations were recited." In the hand of the Jehovah of the Jews disease was a whip of chastisement which fell at will on the chosen people or their enemies. "I will put none of those diseases upon thee which I have brought upon the Egyptians ; for I am the Lord that healeth thee." There is no book of the middle ages down to the eighteenth century, describing an epidemic which does not attribute it to the wrath of God. Job ascribed his own pains to the "arrows of the Almighty." Luther wrote that "pestilence, fever and other severe diseases are naught else than the devil's work." Cotton Mather described disease as "flagellum Dei pro pecatis mundi."

"The American Indian medicine man or the Asiatic Samoyed does his best to frighten away the demons of disease by assuming a terrifying aspect, covering himself with the skins of animals so as to resemble an enormous beast walking on his hind legs, resorting to such demonstrations as shouting, raving, slapping his hands or shaking a rattle, and pretending (or endeavoring) to extract the active principle of the disease by sucking it through a hollow tube. . . . We may smile at these phases of Shamanistic procedure, but, except for the noise, they are not essentially different from the mind-medicine or faithhealing of our own day. Both rely upon psychotherapy and suggestion, and for a sick savage, the fantastic clamor made about him might be conceivably as effective as the quieter methods of Christian Science, to a modern nervous patient." (Garrison.)

20 HISTORICAL REVIEW

A doctrine quite as old, but with a smaller following at present, taught that all the joys and ills of man are determined by the position of the heavenly bodies. Even within the present generation there are those who believe that famine, war and pestilence are determined by the spots on the sun or by the juxtaposition of certain planets. Our great lexicographer, Noah Webster, wrote a book to prove that epidemics are due to earthquakes and other terrestrial disturbances.

Hippocrates taught that epidemics are due to a pestilential condition of the air. This theory dominated the medical profession for more than two thousand years, and still colors some of our conceptions of infection. Quite naturally, such a theory is liable to many modifications. How does the air become pestilential? This question has been answered in numberless ways. Some say it is made so by evil spirits; by an angered God; by the influence of heavenly bodies; by terrestrial disturbances ; by prevailing winds ; by emanations from earth or water; etc. It is natural for man to believe in the evil genius of the locality in which ills befall him. In 1898, intelligent army officers told with bated breath that the word "Chickamauga" means river of death. They believed that the epidemic of typhoid there prevalent was due in part, at least, to the miasm of the locality and the disease was called "Chickamauga fever." The word malaria (mal aria) owes its origin to this theory. In war, unburied bodies of men and animals were supposed to fill the air with deadly decomposition products. It was fear of this that secured burial of the numerous victims of the plague in the great epidemics of the middle ages. This fear had, in part at least, a religious basis, and burial was regarded not only as a necessary sanitary measure, but as a compliance with a divine command. The unburied dead became a reproach to the living ; from the decomposing body noxious and fatal emanations polluted the surrounding air, and with this threatening weapon, the dead demanded the honor of Christian burial.

Lowlands and swamps were supposed to be places in which noxious vapors were generated and from which they spread, poisoning the air of the surrounding country. These localities were shunned, especially after sunset, and the fear of breathing night air became well nigh universal. We now know that the real truth in this belief was made

HISTORICAL REVIEW 21

plain by the discovery of the transmission of malaria by mosquitos. The latest scientific support of the theory of miasm appeared in the teachings of the great sanitarian of Munich, Pettenkoffer. When he began his work in the Bavarian capital, about the middle of the nineteenth century, that city was known as a hotbed of typhoid fever. Fecal matter was deposited in shallow vaults and the drinking-water was taken from shallow wells. The whole city was honeycombed with these privies and wells, and the people were drinking strong infusions of their own excrement. Pettenkoffer taught that the fecal matter undergoes a ripening process in the soil and thereby becomes the cause of typhoid fever. Responding to his teachings, the people of Munich introduced a complete sewerage system and brought a pure drinking-water from a distant mountain lake. This resulted in the eradication of typhoid fever and Pettenkoffer 's theory was justified by the result. We now know that the typhoid bacillus needs no ripening process during the interval which elapses from its passage from the bowels of one to its entrance into the alimentary canal of another. Pettenkoffer's theory did not assume that the noxious agent in the fecal matter is a living organism, but rather held that the ripening process consists of chemical changes. From this, there grew up the idea of the de novo origin of typhoid fever. The fecal matter of uninfected individuals was supposed to undergo ripening processes in the soil and the products of these changes, finding their way into either water or air, distributed the disease. This theory was not only plausible, but was in accord with the then known facts. It found ready support, especially among army medical officers. However healthy men appeared to be when they went into camp, even in locations which could not have been contaminated previously, after a few weeks, typhoid fever appeared and spread in proportion to the filthiness of the camp and the inefficiency of the methods of fecal disposal. Men of the highest intelligence and widest experience became firm supporters of the de novo origin of typhoid fever which they regarded as a filth disease. They believed that the disease was spread by gases generated in any kind of filth, but more especially by those developed in fecal matter.

The theory of miasm was applied not only to typhoid fever and malaria, but to all diseases, especially those appearing in epidemic

22 THEORY OF MIASM

form. With sound sense, the Greek Father of Medicine said that when a large number of people fall ill simultaneously the cause must be sought in that which is common to all, and what can that be save the air they breathe ? It was observed, however, that while the whole community was breathing the same air, many remained well ; some had eruptive diseases; others diarrheal disturbances; and still others, respiratory affections. This necessitated the division of men into groups according to temperament. With the same factor in the air the result would vary with the temperament of the individual.

The study of the cholera epidemics of the nineteenth century removed the last scientific support of the theory of miasm. It had long been a matter of observation and record that epidemics travel from east to west. This was noted before the Christian era. It was frequently observed in classical times, and the cholera pandemics gave opportunity for collecting exact data on this matter. It was found that cholera, which is endemic about the delta of the Ganges, becomes pandemic on the occasion of certain religious pilgrimages. The faithful followers of Mohammed from all points of the compass gather at Mecca. Some come from the home of cholera, bringing the infection in their bodies. From their discharges others become infected, and as the great concourse disperses, bands of returning pilgrims carry the infection with them, and the disease widens its area. It travels just as fast and no faster than man travels. It goes where he carries it and nowhere else. When an individual drops the infection, some one else must pick it up and carry it on or it ceases to spread. The general direction of the spread of infection has always been from east to west because the great lines of human travel have led from this point of the compass, but it was found in the study of the cholera epidemics that whenever and wherever the paths of travel deviated from the general direction, the infection showed the same deviation. In other words, it became evident that infected man carried the infection in his own body. However, when the pandemics spread over Europe it was noticed that, while no place became infected unless visited by some infected individual, the disease established itself in certain localities and failed to do so in other places. This observation gave some support to the theory of miasm. In some soils the seeds of the disease grew and multiplied while in others they did not. When the water-

GERM THEORY 23

supply of a locality became infected, the disease spread among its consumers. Budd of London was probably the first to detect the role of infected water in the dissemination of Asiatic cholera. Finally the discovery of the specific bacteria of cholera and other diseases removed the last support of the theory of disease originating in miasmatic conditions of the atmosphere.

The "germ theory" of disease found lodgment in the brain of an occasional genius many centuries ago. Just who first suggested it and when are not easily determined, but the argument ran something as follows: Alexandria was free from the plague. A ship from a port where it prevailed came with sick on board. Those associated with the new arrivals acquired the disease and it spread in an ever widening circle until it prevailed throughout the city and extended in a similar manner to other countries. The disease must be due to a poison of some kind. It cannot be a chemical poison, like arsenic, but it must be a living thing which finds its way from the body of the sick to those of the well where it grows and multiplies and in so doing causes the symptoms of the disease and death. Thus, man's reason, stimulated by exact observation, caused him to conclude that an epidemic must be due to a contagium vivum. He might theorize concerning this living thing, but he could not demonstrate its existence. It was too small for him to see. In the first century of the Christian era Varro wrote that there are swamps in which grow animals so small that they cannot be seen. They enter the body through the mouth and nose and cause disease. Others wrote to the same effect. Probably the first to see bacteria was the Dutch scientist and lens maker, Leeuwenhoek, who near the end of the seventeenth century described the "animalculae" which he found under his microscope in the examination of tartar from the teeth and diarrheal stools. In 1849 a village doctor on the Rhine, with a crude compound microscope, saw rod-like bodies in the blood of animals sick with anthrax and failed to find them in the blood of healthy animals. The science of bacteriology may be said to owe its birth to these observations. Independently, this work was continued by Brauel, Davaine and others, but the founder of exact and systematic knowledge concerning the causal agents of disease was the great Frenchman, Louis Pasteur.