SOME OF THE TRIUMPHS OF MODERN MEDICINE.
An Address by PROFESSOR LEWELLYS P. BARKER, M.D., LL.D., of Johns Hopkins University, Baltimore, before the Empire Club of Canada, on January 5, 1910.
Mr. President and Gentlemen,
All experience has taught us that properly to judge the significance of events we must not stand too near them. The year just behind us, for example, would seem, to those of us who have but now passed through it, destined to be especially remembered for at least some of its happenings, and yet many of its developments are doubtless far less important than we think them. It seems scarcely probable, however, that we make an over-estimate when we regard as truly epochal events in human history (1) the definite adoption of aerial flight into our system of transportation; (2) the discovery of the North Pole, and (3) the downfall of Turkish absolutism. Though the figures of Orville and Wilbur Wright, Louis Bleriot, Count Zeppelin, Commander Peary and Chevket Pasha may loom larger to us on account of our proximity than they will to those who follow us, it seems reasonable, I think, to believe that the new world-facts for which the names of these men stand, are highly important ones, to which our race is not likely soon to become oblivious.
If we go back a little further than the last year and include the last half century or more it must be borne in upon every one of us that we are living in a truly remarkable age. In the few minutes that are allotted to me for these remarks it is not my purpose to touch in any general way upon the wonders of the age, on the contrary, I desire to limit what I have to say to some brief comments upon the advances made by the branch of knowledge with which I am most familiar, namely Modern Medicine. In the last century mankind has made more progress (1) in understanding the nature of disease, (2) in finding out how to prevent disease, and (3) in discovering cures for disease, than had been made in all time preceding. This great progress has been due to the growth of the biological, physical and chemical sciences, and the application of the methods of these sciences to medical problems by men imbued with the scientific spirit. Observations and experiments have become ever more accurate and fruitfulness has kept pace with precision. A long series of post mortem examinations on patients who had been carefully studied by physicians at the bedside, had given us an idea of the anatomical basis of disease which, though it was a necessary preliminary to the study of the causes of disease which was to follow, for a time made medical men somewhat hopeless about prevention and more so about cure.
The researches of Pasteur and Koch in the last quarter of the last century started an entirely new era in our knowledge of the causes of infectious diseases. The discovery that this group of diseases is due to parasitism, to infection of the body by minute vegetable organisms, the bacteria, or to invasion of the body by microscopic animal organisms, the protozoa, formed the broad and fruitful basis for the development of modern preventive measures against infectious processes. Once the causes of such diseases were known and once we had become familiar with the extra-corporeal habitations of the parasites, the way was opened up for finding out the mode of infection or invasion and for prevention. Preventive medicine had, it is true, scored two great triumphs before these studies were made. I refer to (1) the wonderful discovery by Jenner of vaccination against smallpox made toward the end of the eighteenth century, and (2) Captain Cook's application of bind's methods to the prevention of scurvy.
The great series of triumphs was, however, to follow upon etiological studies made by men trained in bacteriology and parasitology. A brief survey of some of the more important results achieved will convince you of the enormous progress which has marked the years since 1876. Among the diseases of known bacterial origin--the following are now classed among the preventable diseases Tuberculosis, diphtheria, tetanus, Malta fever, Bubonic plague, puerperal fever, wound infection, summer diarrhoea of children, Asiatic cholera, typhoid fever, and the venereal diseases (gonorrhea and syphilis). Among the diseases due to protozoa which have been studied and in which the mode of infection is known and preventable may be mentioned malaria and sleeping sickness. Of diseases like yellow fever, hydrophobia, and smallpox which are preventable, though the virus is as yet unknown, I shall have something to say later on.
Tuberculosis formerly slew one out of every eight human beings; nearly every person who lives to his thirtieth year carries somewhere in his body some healed or unhealed focus of tuberculous infection. Now that the bacillus which causes it is known, and the portals of entry of the bacillus into the human body have been discovered; now that we fear a tuberculous ancestry less than a tuberculous propinquity; since we have refined methods of diagnosis which permit us to recognize the existence of a tuberculous infection in its very early stages, and have learned the curative effects of sanitary living (rest, good food, fresh air, wholesome surroundings), we are prepared for battle with this chief among the agencies of death. The public has joined the medical profession in the waging of this war against tuberculosis and a world-wide movement of prevention has been begun which bids fair to be successful. Within twenty years in those portions of the United States in which the causes of death are registered there has been a decline in the death rate from tuberculosis of about 30 per cent. When methods of prevention become more generally known and more perfectly applied the disease will diminish very rapidly and may ultimately be exterminated.
Diphtheria is a disease which, if we lived up to our knowledge, need scarcely be feared, though formerly it was one of the most terrible of scourges, destroying half of the persons it attacked. Following upon the discovery of its causative bacillus a mode of immunizing animals against it was worked out and Behring demonstrated that the introduction of some of the blood serum of an animal so immunized into the body of a person recently infected would rapidly cure the disease. More than this, if small quantities of this antitoxin are given to persons who have been, exposed to the disease by contact they will not have diphtheria. As a curative agent this antitoxin has reduced the mortality of diphtheria from more than 50 percent to less than 10 per cent. The incidence of the disease has been greatly lessened since its cause has been found out. In New York city alone the death rate per year from diphtheria has been reduced by 3,000 (W. H. Park).
Tetanus or lockjaw was found to be due to-an anaerobic bacillus, i.e., to one that does not multiply except when excluded from the air. This fact together with the prevalence of the spore forms of the bacillus in garden earth explains the frequency of the disease after deeply punctured wounds (e.g., from rusty nails or from Fourth of July explosions in the dirty hands of small boys). Today if an injury occurs which experience tells us is prone to be followed by tetanic infection, a dose of tetanus antitoxin promptly administered will surely prevent the development of the disease. Occasionally a life can be saved by this antitoxin after the symptoms of tetanus have appeared, but this agent is far more efficacious for prevention than for cure.
Malta fever, a long continued disease, common in the Mediterranean and found to be caused by a special coccal bacterial form, is controllable since it has been demonstrated that the vehicle of dissemination of the bacteria is the milk of goats. Bubonic plague, a disease which at intervals has swept over the whole world, familiar to all who recall their history as the terrible Black Death of Europe and the plague described by Pepys and Defoe, will never again devastate the more civilized portions of the earth. Due to a bacillus which is kept alive in the bodies of living rats and squirrels and transferred to human bodies largely through the bites of insects we have the cue for our protection. Puerperal or child-bed fever, wholly misunderstood in its nature until Oliver Wendell Holmes demonstrated that it is a contagious disease brought to unfortunate women by the contaminated fingers of physician, midwife or nurse, has been found to be due to preventable bacterial infection. In former times the deaths from puerperal fever in maternity hospitals were appalling. From October, 1841, to May, 1843, in Vienna, of 5,139 women delivered no less than 829 died, and in Paris, in 1864, of 1,350 women delivered, 310 died. It was not surprising that women came to look upon the lying-in hospital as the "vestibule of death." Since the methods of antisepsis and asepsis were introduced by Sir Joseph Lister, based upon the bacteriological studies of Pasteur, the death rate in maternity hospitals has been steadily reduced until today it is only about 0.02 percent or 2 deaths in 10,000 cases!
The antiseptic and aseptic treatment of wounds, including those resulting from accident and also those due to surgical operations, not only reduced mortality directly but also, together with anaesthesia, extended enormously the possibilities of surgery. Before Lister's time a compound fracture of the leg meant only too surely death or amputation; since then recovery is almost certain with a retained limb. Farther, as Mr. Eliot has recently emphasized in his inspiring Ether-Day lecture (Oct. 16, 1909), asepticism and anaesthesia "have opened a great field of animal experimentation, which has already yielded invaluable additions to our knowledge of physiology, pharmacology and pathology" . . . They have been indispensable to the medical research of the last forty years." The summer diarrhoeas of children still kill an enormous number in the first three years of life, but a pure milk and water supply, cleanliness, fresh air and good nursing are rapidly reducing this mortality.
Asiatic cholera, capable as everyone knows of killing at a stroke a large proportion of the inhabitants of a great city, formerly, once started westward, was only too likely to encircle the globe in a huge pandemic. It has done its worst work; it will never again cause a national epidemic unless men forget what we now know or fail to make use of the knowledge we possess. The comma bacillus discovered by Koch lives only in certain media and is spread only in definite ways; public health officers can speedily detect its presence and, warning a community, can protect the inhabitants from infection. Note how speedily the disease was stamped out in Holland last summer after the introduction of the infective agent into Rotterdam by a ship from Russia. A few years ago had Rotterdam been so contaminated the disease would have spread like wild-fire through Holland, and over Eastern Europe, and American summer visitors would have found themselves unable to return home as they would have been imprisoned by quarantine regulations.
Typhoid fever, also due to a bacillus, which enters the body chiefly in impure water but sometimes in milk or other foods, is distinctly a preventable disease. In many places by providing a pure water and milk supply the disease has been almost eradicated. In the larger towns in Germany between 1877 and 1881 the average death rate per year from typhoid fever for every 100,000 people was 43.6; in 19o6 this was reduced to only 6.1. The disease still prevails to a shameful extent, in the United States and Canada. In the United States alone 100,000 people die of typhoid yearly. One out of every four American soldiers in the Spanish war contracted the disease.
The venereal diseases, gonorrhoea and syphilis, are due to bacteria--the former to a micrococcus, the latter to a spirochaete. These diseases do untold harm not only to men who contract them but also when insufficiently treated--and generally they are insufficiently treated-to their wives if they marry and to their children. If young men were taught the nature and danger of venereal infection much of it would be avoided and thousands of men, women and children would be spared months and years of misery. A large proportion of cases of sterility in men are due to gonorrhoea, and probably the majority of diseases peculiar to women requiring operation are due to gonorrhoea unwittingly communicated by husbands. It is believed now that general paresis and locomotor ataxia occur only in individuals who have had syphilis, contracted by themselves or inherited from a parent. The best preventive measure against venereal diseases is chastity; next to that regulation of prostitution; and, finally, the diseases may be prevented in the exposed by certain prophylactic measures. A very great deal of blindness in the newly-born is due to infection of the child's eyes with the gonorrhoeal microorganisms as it passes from its mother into the world. All this blindness can be prevented by instilling two drops of a weak solution of silver nitrate (1 percent) into the eyes of each newborn child.
Malaria, the bane of hot countries, the blight of the Roman Campagna, and one of the principal barriers to tropical development has been found to be due to minute animal parasites which live out one portion of their life cycle in a particular variety of mosquito, the other portion of it in human blood. No human being gets malaria unless bitten by an infected anopheles mosquito; no mosquito gets malaria except by feeding on the blood of a malarial human being. These facts permit us to control the spread of the disease. In regions where malaria exists in the mosquitoes we may destroy them or prevent men being bitten by them; if a malarial patient enters a region whose mosquitoes are not infected, he may be screened off until the parasites in his blood have been killed by the administering of quinine. The disease is preventable; by thorough application of the knowledge we possess it could probably be eradicated. The sleepingsickness of Africa, due to an animal parasite, the trypanosoma, is transmitted to man by the bite of a fly. Prevent the Tsetse fly bite and you prevent trypanosomiasis and sleeping sickness. Tropical dysentery is a third disease due to a protozoa parasite, the amoeba coli taken in with impure water.
Turning now for a moment from those diseases due to bacteria and protozoa I must mention three diseases whose causal virus is unknown. Whatever their virus is, it must be extremely minute, as it will pass through a filter which will not permit known bacteria, and protozoa to pass. Smallpox is one of these, easily controllable by vaccination. In the 28 years before vaccination was practised in Sweden the annual death rate from smallpox was 2,0 50 for every million of population; in the 4o years following the introduction of vaccination the annual death-rate was only 1 58 per million. In the Prussian army there has not been a single death from smallpox since the enforcement of the vaccination law of 1874. Hydrophobia or rabies is a second disease of this type. Its cause is unknown, but by animal, experiment Pasteur found out how to prevent its development in human beings bitten by mad dogs. Thousands of lives are saved yearly by preventive inoculation after the bite with an emulsion of the spinal cord of rabbits containing the attenuated virus.
Thirdly, yellow fever due to an unknown virus, was found by Reed, Carroll, Lazear and Agramonte to be communicated to man only through the bite of a particular mosquito known as the Stegomyia. The mosquito is in turn infected by the blood of men suffering frond the disease, but fortunately there is only' a period of three days during which a patient can infect the mosquitoes which bite him. Yellow fever killed hundreds of thousands in Cuba, Mexico and the Southern States. In the light of our new knowledge it is far easier to control than malaria. Colonel Gorgas, applying this knowledge, has practically eradicated the disease from Havana and from the Panama Canal Zone. There is no reason why the disease should not be banished from the earth.
Many more examples of modern medical triumphs might be presented if time permitted, but you will agree that these are enough to illustrate recent advances. One of the latest conquests should not go without a word. I refer to Flexner's studies of the dreadfully fatal or maiming disease known as cerebro-spinal meningitis. By animal experimentation requiring the use of about 25 monkeys and a hundred guinea pigs Flexner has discovered how to use a serum which will save the lives of most persons affected. Almost 1,000 human beings have been treated with this serum; formerly 70 to 80 percent died and 20 to 30 percent recovered; with his serum 70 or 80 percent recover, and only 20 to 30 percent die. Thus, in the two or three years since it has been used at least 500 human lives have been saved by it. Surely such a showing--for the sacrifice of 25 monkeys and 100 guinea pigs ought of itself to silence the antivivisectionists forever.
The public at large has only begun to appreciate what modern medicine is doing to prevent disease. A favourable symptom, however, emphasized recently by Professor William H. Welch in an address before the Political Economy Club of Baltimore, is the notable interest in the prevention of disease which is being manifested by leading economists. Men like Professor Irving Fisher of Yale, Professor Willcox, of Cornell, Professor Glover, of Ann Arbor, are calling attention to the enormous waste due to preventable diseases. They estimate that the economic loss to the United States alone from preventable diseases amounts to many millions of dollars per year. How accurate their calculations are I am unable to judge, but if their attempts to measure the waste in terms of hard cash serves to awaken the public to the urgent need of applying the knowledge medicine has furnished for prevention, physicians will rejoice. In a commercial age economic considerations are sometimes more influential than the merely humanitarian!
Co-incident with measures undertaken directly for the prevention of disease society benefits indirectly in many ways. Think, for example, of the improvement in the general health of our people which has resulted from the anti-tuberculosis campaign! People sleep with their windows open or on porches; promiscuous expectoration in street cars and on the sidewalks has been prohibited by law; poorer people are being better housed; public buildings and public conveyances are being better ventilated; the hours of work and the conditions of life of the labouring classes are being regulated--indeed, great progress is making in personal and social hygiene. The general resistance to disease is being heightened and human beings enjoy more vigour than was possible before these reforms were introduced. Most people are astounded when told that during the last century the death rate has declined one-half, and the expectation of life increased by 10 or 12 years. In the prevention of typhoid fever and cholera infantum, it has become necessary to have pure water and clean milk. The fight against mosquitoes, malaria and yellow fever has led to the conversion of swamps and marshes into arable land. The extermination of rats in plague districts results in an enormous economic saving of stored goods which the rats would otherwise have destroyed. The prevention of alcoholism and venereal diseases will rob lunatic and idiot asylums, alms-houses and prisons of a large proportion of their inmates.
Fully to realize the benefits of preventive. medicine it is necessary to have the co-operation of individuals, of social organizations and of governmental agencies in each town, each Province, and in the whole State. Each individual should be educated in the home and in the schools in the fundamental facts of personal hygiene; societies of various sorts for public health and social welfare purposes can do much, especially in initiating movements or undertaking work which later on can be turned over to the authorities of town or state. The antituberculous crusade begun in this way has already begun to be looked after by municipal and state hearth officers. Nurses, physicians, charity workers, and philanthropists do much by organization in groups with specific health-improvement purposes in view.
It is, however, becoming more and more the function of government to deal with these matters. In the United States and Canada we are far behind England or Germany in Government care of the public health. Our laws are very deficient; we have very few trained sanitarians, experts in public health matters, the public generally (and too often medical men themselves) fail to realize that the average medical practitioner has almost no knowledge of sanitary science in the technical sense. We have no Institutes of Hygiene and Sanitary Science where such experts can be trained, though every University in Germany has its special institute of hygiene. To become a public health officer in England one must in addition to the ordinary medical education undertake special study and training leading to a "diploma in public health." Public health matters should, of course, be entirely divorced from politics. It should be regarded as a public scandal if public health officers, hospital appointee, asylum superintendents and the like are changed simply because of a change in political administration.
I have heard from Dr. McPhedran that interest has grown rapidly here in Canada in the matters of water supply, disposal of sewage, the prevention of tuberculosis and typhoid, and especially in sanitary housing of the poor. It came to me as a surprise, however, to learn on questioning Dr. Amyot that your Public Health law is some 30 years old. Ought you not to have a Commission appointed to undertake its revision? I should think it would be difficult to do the work of today satisfactorily under regulations framed so long ago. It is extremely desirable that there be a definite fixing of responsibility upon municipal, county, provincial, and Dominion health authorities and that the activities of all these authorities be properly co-ordinated and made cooperative. All health officers should be trained sanitarians, provided with liberal salaries, and the more important positions at least should be held by men who give their whole time to the work, and do not engage in the practice of medicine. Much money would necessarily be expended, but the saving of waste from preventable diseases in the town, county and state would be very great.
Canada is at this time astonishing the world by the advances it is making in material prosperity. The outlook for the future from its rich farms, its unexhausted forests, its enormous ore deposits, and its manufacturing activities is particularly bright. In this prosperity Canadians are not likely to forget the importance of the physical and mental welfare of the people. I believe that they will realize more quickly than most nations the value of the investment of large sums of money in medical research, and that there will be no difficulty in enlisting the aid of wealthy private individuals, and of the Government in its endowment. You will too, I feel sure, quickly act upon the idea that much money will be saved and great misery avoided by providing he means for putting into practice the newer knowledge of prevention of disease of which I have spoken.