FACTORS CAUSING PHTHISIS: BACILLI-DAMPNESS-HEREDITY.

BY WM, F. WHYTE, M. D., OF WATERTOWN.

The essential cause of tuberculosis is the bacillus discovered by Koch. This being admitted, all that concerns us in this paper is the consideration of the means by which it enters the human body, and the conditions which are favorable to its entrance and subsequent development.

Tuberculosis is essentially a disease of weaklings.

The ancient Greeks who allowed all feeble and poorly developed children to die, undoubtedly prevented, to some extent, the prevalence and propagation of tuberculosis.

In medical books and journals published before the discovery of Koch, mention is frequently made of a tubercular diathesis, and, no doubt, there exists what may be called the pretuberculous condition.

Tyndale, of New York, makes the starting point from an impaired general condition, holding as a maxim that localized tuberculosis does not endanger life, so long as the general nutrition begets a reasonable resisting power from the tissues.

The symptoms of the pretuberculous condition he describes as all more than temporary departures from well being, of which the person has been conscious for weeks or perhaps months, and which by careful diagnosis cannot be made to fit into the frame of a recognized trouble, acute or chronic, functional or organic. There is a falling off in the daily routine of eating, breathing, elasticity in walking, refreshing sleep, buoyant mind, to which are added vague disturbances of sensation. Correct appreciation of this condition can only be reached by exclusion.

I have no doubt that imperfect assimilation of food or impaired nutrition caused by improper or insufficient diet, is in

adult life one of the foremost factors in allowing the bacillus to obtain a lodgement in the tissues. When once entrenched, the same conditions which allowed the first deposit will aid in the proliferation of the germs, and the fight of the leucocytes with the invader can only have one termination.

Gould sums up the question of prophylaxis in these words: "The prophylaxis of tuberculosis must begin before birth. The system must be rendered impregnable to the invasion of a disease agent that is practically omnipresent. The invasion once accomplished, the struggle is an unequal one. The enemy once entrenched, his expulsion is a matter of difficulty. The only hopeful means must be on the lines of physiological resistance. The soil must be rendered sterile. A healthy condition of fluids and tissues best fulfills the indication, in that it is antagonistic to bacterial growth and activity."

Dampness is without doubt an important factor in promoting the development of the bacillus. We all have heard, times without number, from our tuberculous patients, complaints of the dampness of the atmosphere. Cases which run their course without change of climate progress more slowly in a dry season, while change of surroundings from the city to the country often causes an arrest of the disease or a great amelioration of the symptoms.

Sanitariums for consumptives, without exception, are situated in mountainous regions, as in North Carolina, Switzerland, The Adirondacks and in Colorado.

Atmospheric dryness is one characteristic of the climate of Colorado. Of equal importance is the dryness of the sandy and porous soil which absorbs moisture rapidly.

The mean absolute humidity of Denver is one-half that of New York and Los Angeles, and one-third that of Jacksonville.

Dennison is authority for the statement that one-third of the adult inhabitants of the State, born outside of its territory,

have become residents because they had some form of tuberculosis.

A most common cause of infection is the inhalation of dried tuberculous sputum.

Cornet's investigations show that the dust of localities frequented by patients with pulmonary tuberculosis, possesses great infectiveness. Sputum containing the bacillus is exceedingly infectious, retaining its virulence in dilution of I to 100,000, the virulence of the sputum being in proportion to the quantity of bacilli present. Gebhardt employed pure cultures of the bacillus of tuberculosis, on the hypothesis that equal quantities of the same culture contain equal quantities of bacilli, with a subcutaneous inoculation of a dilution in the proportion of 1 to 400,000.

He obtained positive results.

"Malasses and Vignal desiccated the sputum of tuberculosis, moistened it with water, again desiccated and pulverized it, and this repeatedly, endeavoring to realize so far as possible the condition to which the sputum daily ejected into the streets is subjected. After this treatment, the bacillus retained all its virulence." At the congress of 'Deutsche Aertze' und Natur furscher in 1890, Schotelius stated that he had instituted a number of experiments with tuberculous lungs interred in a wooden box at a depth of five feet, the usual method of sepulture. After two and a half years, he found in the surrounding earth a quantity of spores producing tubercle bacilli. He advises the disinfection of bodies dead from infectious diseases. This highly practical and vital suggestion can never be carried out owing to lay prejudice. We are all aware of the difficulties in the way of an autopsy in private practice, and as to disinfecting the bodies of those who die of tuberculosis, that can only be carried out when public opinion and statute law make cremation the substitute for burial.

Gebhardt's experiments go to show that the digestive ap

paratus offers more resistance to infection than the lungs or peritoneum.

The transmission of the bacillus by food is another important factor.

During the past few years our State Boards of Health, veterinary societies and schools of agriculture, have been making investigations on the subject of bovine tuberculosis, which will tend to arouse public sentiment by causing the laity to become in some degree, at least, conversant with the danger of the use of meat and milk which have been infected with tubercular bacilli.

The percentage of tuberculous cows in the city dairy stables is very large, and it has been stated by good authorities that the dairy stock of the eastern states is from ten to fifteen per cent. tuberculous. Even this is regarded as a low estimate. Infection by milk is undoubtedly the cause of a large proportion of the tuberculosis of the intestinal tract and the mesenteric glands in infants. No doubt many of the fatal cases which we see of enterocolitis are tuberculous.

Woodhead's analysis of 127 cases of fatal tuberculosis in children showed that in 100 cases the mesenteric glands were affected.

Experiments have shown that the feeding of animals with the milk of cows known to be tuberculous, has caused infection of the digestive passages. Hirshberger states that the owner of a herd of cows known to be tuberculous, withdrew the milk from the market and used it to fatten his pigs. The result was they all became tuberculous and had to be slaughtered.

The

This source of infection is absolutely under control. sterilization of all milk fed to infants will without doubt remove one factor in the production of tuberculosis.

The Pasteurization of milk, so-called, is a step in the right direction, although it is to be feared that as it is usually carried out, it does not kill the bacillus. Dr. H. L. Russell, of

the Wisconsin Agricultural Experiment Station, in the May number of the Pharmaceutical Review, says that if properly carried out at a temperature of 155° to 160° Fahr., all germs found in milk are destroyed.

Infection by the ingestion of tuberculous meat is much more rare, as most of the meat consumed by civilized man is thoroughly cooked, with the exception of some kinds of sausage and underdone beefsteak, which is not subjected to a temperature of more than 150°.

The hereditary transmission of tuberculosis is from the maternal side. There is no evidence to show that a tuberculous father can transmit the disease to his offspring. To the seminal fluid of tuberculous man and male animals may be attributed genital tuberculosis in the female. In my own practice I can recall the case of a posthumous child of a tuberculous father which died in the third month of tuberculous meningitis.

The infant, however, was born and lived in the house which its father had inhabited several years before his death, so that other sources of infection, rather than heredity, were in all probability the cause of death.

There are a number of cases recorded of congenital tuberculosis. Jacobi reports having seen one in which the fetus born at the seventh month had miliary granulations in the liver, spleen, peritoneum and right pleura. Gaertner, of Jena, in his investigations, shows that in mice, rabbits and canary birds, tubercle bacilli often pass from mother to fetus.

The infection probably takes place through the placenta in mammals, and, occurring during the last part of fetal life does not show the characteristic lesions at birth.

Baumgartner's theory is that the virus is transmitted through the mother, but remains latent until some time after birth.

He regards its development as analogous to syphilis hered