2. Varying Malignancy of the Tubercle Bacillus in Man. Nothing is more familiar to physicians than the slow progress of tuberculosis of the lymph-glands and bones, on the one hand, and its frequent rapid progress in pulmonary, abdominal, or encephalic organs on the other. It has on this account been rather difficult to persuade many of the etiological identity of scrofula and consumption. In experimental tuberculosis the same truth constantly crops up. Arloing and his followers found that the tubercle bacillus from the lymph-glands of man proved less virulent and deadly than that from the human lungs (Lecons sur la Tuberculose). As early as 1880, Creighton drew attention to this in his work on Bovine Tuberculosis in Man.

But the bacillus from the lungs is subject to variations of this kind. Among seven specimens of human sputum, cultivated by Theobald Smith, six had a fair average vitality, while the seventh failed to perpetuate itself on dog serum.^[4]

It should be strongly emphasized in this connection that the failure of extension and generalization of the sputum germ when transferred to cattle does not distinguish it from the tubercle bacillus as conveyed from ox to ox. Everyone at all experienced with the tuberculin test well knows that in most herds the majority of the tuberculous animals show no generalization, but only a localized tuberculosis. There is reason to believe that even recoveries take place after slight infection, and it is certain that many tuberculous cattle continue for years in what appears to be good general health. Unless in particularly susceptible subjects or under specially poor hygienic conditions, or unless in case of reinfection, the average bacillus of bovine origin habitually fails to produce in other cattle a rapid extension and generalization.

3. Interchangeability of Bacillus of Man and Bird. Of all known forms of tubercle bacillus that of birds is the most distant from that of man or ox, and yet the beautiful experiments of Nocard^[5] serve to establish their essential identity. Taking the bacillus of human sputum, which would not infect the fowl, he enclosed it in collodion capsules, which confined the bacilli while allowing transudation of the animal fluids, and left these in the abdomen of the chicken for not less than four months. He repeated this three times in succession with the product of the original sputum germ, and obtained a bacillus which was actively pathogenic for the chicken, though it had been harmless after the sojourn of four and eight months respectively.

This may explain the reported cases in which a flock of poultry have developed tuberculosis a few months after they were placed in the hands of a consumptive caretaker. That such transmission does not always occur is not surprising, considering that transmission between man and man is infrequent in comparison with the number of exposures. So in cattle the majority of exposed animals usually escape, although in such a case there can be no plausible explanation on the ground of a difference of germ. We have in every case to consider the necessity for receptivity as well as infectivity, and the lack of either is a bar to infection. When, however, we assume that the most diverse tubercle bacilli are descendent’s of one original stock, that a large herd must furnish some animals of more than usual susceptibility, and that such animals are subjected to continuous accessions of both bacilli and toxins, we can easily understand how some of the more adaptable germs will in time accommodate themselves to the new medium. A Pettinkoffer, with an immune constitution or a specially vigorous gastric digestion, may with impunity drink a culture of cholera spirillum, but the same is not true of the drunkard fresh from a spree and with seriously impaired digestion.

Bacillus Tuberculosis in Man and Ox. Points of Similarity. The bacillus tuberculosis of cattle is in general shorter and thicker than those of man, but many in both subjects are morphologically indistinguishable. Such differences are often far exceeded by different specimens of one stock of germ seeded on different media. There is no great difference in the thermal death point, and the viability in light, dryness, cold and putrefaction. The tendency is in all cases to colonize the lymph plexus or glands and to develop the specific lesions, with slight variation in detail. The slow development of the lesions from both forms of bacilli and their histological similarity is another argument for their essential identity. The slow growth of both on artificial media, the demand of each for a medium having the same approximate composition, and the similar pathogenic and diagnostic characters of the toxic matters elaborated by both germs bespeak a primary identity. The very remarkable staining qualities of tubercle bacillus, from whatever source it may be drawn, are no less remarkable.

Tuberculosis of Man and Ox Coextensive. The prevalence of tuberculosis in man and ox in the same country and district is so frequent that it may be safely set down as the rule. Among ichthyophagists and great fishing communities, like the people of the Hebrides, Iceland, Newfoundland, Greenland, and the coasts of Hudson Bay, tuberculosis is rare. In these countries cattle are few or absent, or, like the hardy highland kyloes of the Hebrides, they are kept in the open air. The immunity of the people is not due to insusceptibility, since they fall ready victims to tuberculosis when removed to infected countries and cities.

In Northern Sweden, Norway, Lapland and Finland, where cattle are scarce and reindeer plentiful, tuberculosis is said to be rare, though the inhabitants live in the closest of dwellings through the long winter. In most of the Pacific islands there are no cattle, and the natives are comparatively free from consumption. In Hawaii, since the introduction of cattle, consumption has increased. Australia and Tasmania, which forty years ago were the great resorts for English consumptives, have become increasingly the homes of infection since the development of the cattle industry and the influx of phthisical subjects. Minnesota and Dakota, in the early days, were held to be incompatible with tuberculosis, but since the advent of the white man and his stabled herds they have largely lost their sanitary reputation. The highest known mortality from tuberculosis to-day is that of the reservation Indians of these States, who feed on raw, diseased beef. In the Kighiz steppes the Tartars subsist on the flesh and milk of their solipeds, and largely escape consumption. In Japan, Dr. Ashmead tells us that the common people escape tuberculosis, while the aristocracy suffer severely. He attributes this mainly to the debauchery of the ruling class; but it must not be overlooked that they eat freely of beef and dairy products, which the rice-eating poorer population do not. The same remarks apply in measure to the mandarin and plebian classes in China. Holden tells us that tuberculosis is rare in Columbia, Ecuador and on the eastern slopes of the Andes, where little or no milk or butter is used. It must be further borne in mind that in these countries all herds live in the open air, and practically escape infection.

These examples must be contrasted with the consumers of beef and milk in civilized temperate countries, where the stock are largely kept indoors. A general average mortality of 7 or 8 per cent. from tuberculosis, and the post mortem evidence in European and American hospitals of 33 to 50 per cent. which show tubercular lesions, recent or remote, cannot be lightly passed over. The contrast with our reservation Indians is still more striking. Holden and Treon testify that the meat furnished to the Indians is always poor and often diseased, and that when the stock arrives our hungry wards devour the internal organs raw, or, later, the flesh as pounded preserved meat, and still uncooked. The deaths of these Indians from tuberculosis is 50 per cent. of the total mortality.^[6] Dr. Washington Matthews, who spent twenty-one years among the Indians, gives their food as the main cause of the disease, and states that when the supply of fresh meat is liberal the death rate from tuberculosis is highest (Census of 1880).

If we now contrast this fearful mortality with the immunity of the Indians of Hudson Bay, Great Slave Lake, Alaska, and the North generally, we have a most suggestive picture. It may be conceded that the extreme Northern Indians, being beyond the cereal region, have a slight measure of protection in their meat diet; but the recent spread of tuberculosis, like a plague, among the inhabitants of Barrow Straits, when introduced by the frozen-in whalers and the relief party, is sufficient disproof of any claim of special insusceptibility. There can be no doubt that in this, as in other virulent diseases, the rule holds that the long absence of the infection secures the preservation of the susceptible lines of blood, so that when the contagion does come it finds a more inviting field than in countries in which the more susceptible strains have been killed off and the comparatively immune have survived. Toward the Arctic circle the Indian must crowd into closer quarters in winter than his brother further south; but, in spite of all, the beef-eating Indian is being rapidly exterminated by tuberculosis, to which his brother of the north is a comparative stranger.

Exceptions: Their Explanation. This statement would be incomplete without a notice of exceptions to the rule. The Cape Town branch of the British Medical Association reports “that tuberculosis is rapidly increasing there in the human population, while tubercle in cattle is almost nonexistent.” This finds an abundant explanation in the different conditions of life. The men live indoors and concentrate the infection, whereas the cattle enjoy an outdoor life and escape. In a latitude of 30° south, where frost is rare, and with a dry climate (12 to 30 inches of rain per annum), the colonists find no occasion for housing their cattle, so that the conditions for the prevention of tuberculosis are ideal. It may be added that cattle are far less numerous in Cape Colony than they formerly were. The destruction first by lung plague and later by rinderpest has made the cattle industry extremely hazardous, and even before the advent of the rinderpest many had abandoned cattle and taken to sheep.

Parallel cases can be found in other countries. In Egypt, the great resort of consumptives, cattle are almost immune, the abattoirs furnishing about one tuberculous ox in ten thousand killed.^[7] From Tunis (Alix), Algiers (Sarciron, Plaise), and Senegambia (Lenoir) a similar testimony comes. Cattle imported from Europe may die of tuberculosis, which is liable to assume a rapidly fatal type; but the native cattle, kept in the open air, are practically exempt.

Jersey cattle in their native island, staked out at pasture all the year round, show little or no tuberculosis, whereas the housed Jerseys of England and America suffer severely. The cattle of our Gulf Coast States, kept on ranches in the open air, are largely immune, and the cattle of Columbia, Ecuador, Peru, and the Argentine Republic largely escape; but the housed dairy cows of our Southern cities show a very high ratio of consumptives. Consumption becomes more and more deadly in the Southern negro even in the country localities, while the outdoor cattle of the same districts escape.

The absence of tuberculosis from the sanitarium herd at Saranac requires to be explained on a different basis. This herd is housed in winter, and infection, once introduced, would have opportunity to spread. The absence of tuberculosis is highly complimentary to the management of the establishment. But a similar immunity is the rule for all well-managed sanitariums, and not as regards cattle only, but man as well. At Argeles no case of tuberculosis contagion to attendants occurred in ten years (Ferrand). At Soden baths, in a village of 1500, there were in thirty-four years 65 deaths, 15 from consumption (Hopt). At Falkenstein, in fifteen years, one attendant became tuberculous (Jousset). At Görbersdorf the cases of consumption in the village and environs decreased (Knopf). At Brompton, London, in thirty-six years, among 150 attendants, but one became consumptive, though they individually served for from fifteen to twenty-four years, and nearly 40,000 patients had been received.^[8] A well-conducted sanitarium is and should be a safer place than the average community, in which 15 per cent. and upward are tuberculous. The educational influence of such an institution should decrease tuberculosis in the surrounding districts.

Cases of Direct Infection from Man to Ox. Chauveau induced tuberculosis in cattle by feeding the tubercle from the lungs of man.^[9]

Nocard relates that a Beauce farmer, with a finely appointed stable and healthy herd, in 1883 employed a dairyman who had cough, profuse expectoration, and occasional hæmoptysis, and who had been several times in the hospital in consequence. He slept in the cow stable directly over the cows. In 1886 two cows, stalled immediately beneath him, showed ill health and were put up to fatten, but did badly and showed extensive tuberculosis when butchered. The dairyman stayed until 1891, having to go to the hospital several times in the interval. In 1892 the tuberculin test was applied and seven more cows were found to be tuberculous.

Huon tells of a cow bought to furnish milk for calves used to raise vaccine. She stood the tuberculin test, and was carefully secluded from all other cattle, but soon began to fall off, and in six months was very much emaciated, responded to the tuberculin test, and when killed showed extensive tuberculosis. Her caretaker at the vaccine establishment had what was believed to be chronic bronchitis, but when he died, soon after, this was found to be extensive pulmonary tuberculosis.

Bollinger inoculated a three-months’ calf with liquid from human tubercle and killed it seven months later. Fibroid pedunculated tumors, from a pea to a walnut in size, hung from the mesentery and spleen, and the mesenteric and retroperitoneal glands were tubercular.^[10]

Sidney Martin furnishes the following: Four calves were fed 70 c.c. of sputum containing a large number of bacilli. Three were killed after four, eight, and twelve months respectively, and had severally 53, 63 and 13 nodules on the small intestine, mostly on Peyers’ patches. Two calves received at one dose 440 c.c. of tuberculous sputum, and were severally killed after eight and nineteen weeks. The first had tubercular nodules in the intestine and mesenteric glands.^[11]

Frothingham injected into the peritoneum of two calves, three and thirteen weeks old, a culture of tubercle bacilli isolated one year before from the liver of a child. Slight local nodules were produced, some like spontaneous tubercle, others granulation tissue.

Theobald Smith inoculated sputum into the chest and abdomen of the following:

1. A yearling heifer, which was killed two months later and showed on the pleura near the seat of infection a mass of tubercles, one by one and a half inch in diameter, with partly caseated centres; also a nodule one-eighth of an inch on the right lung, and small tubercles attached to the diaphragm and omentum.

2. A yearling injected in the same way showed in two months on the diaphragm a mass of tubercles two inches in diameter, and a second mass one inch in diameter on the ribs near the seat of infection. Microscopical examination failed to detect bacilli, but there is no evidence that they were sought by culture or inoculation.

3. A cow injected in the chest and killed after two months showed tubercles of the lungs, pleura, and mediastinal glands, partly caseated and containing bacilli. Vascular fringes hung from the pleura.

4. A cow receiving a chest injection of sputum culture and killed in two months showed fringes and pendulous masses on the pleura, with small tubercles containing cheesy matter and a few bacilli.^[12]

Crookshank injected tubercular sputum into the peritoneum of a calf, which died of streptococcus infection on the forty-second day. It showed extensive tubercular deposits in the seat of injection and an abscess the size of a walnut. Nodular fleshy neoplasms in hundreds studded the mesentery, omentum, liver, spleen, and diaphragm, and small tubercles disseminated through the lungs and liver contained tubercle bacilli. Three abscesses contained streptococci.^[13]

The experimental inoculations of cattle with sputum by T. Smith, Kruse, and Adami showed a decided lack of potency in the bovine system, but (1) they do not show that the germ at once perishes in the system of cattle; (2) they do not prove that this germ, if returned from the ox to man, would prove less pathogenic than if carried from man to man without the intervention of the ox. (3) The observations of Bollinger, Baumgarten, and Crookshank show that under certain conditions the sputum bacillus can and does produce generalized tuberculosis in cattle. (4) Diminished pathogenesis of the germ when passed from man to cattle is no guarantee that this germ, or the slightly modified germ of casual bovine tuberculosis will prove equally mild if transferred from the bovine to the human patient.

Cases of Infection of Man from Ox. Tscherning, of Copenhagen, attended a young veterinarian who had cut his finger in dissecting a tuberculous cow. The skin wound healed in three weeks, but a subcutaneous swelling persisted, an ulcer formed, and a tuberculous mass containing bacilli was removed. No secondary tubercles formed.^[14] A parallel case occurred to a prominent American veterinarian. The diseased tissue was excised and the bacilli identified by the bacteriologist of the university with which the patient was connected, and a permanent recovery ensued.

Pfeiffer, of Weimar, attended a veterinarian who had been similarly inoculated from a tuberculous cow. The patient, aged thirty-four years, had a good constitution and no tuberculous taint. The cutaneous lesion healed, but six months later there was tuberculosis in the cicatrix; pulmonary tuberculosis followed, and the patient died of this two years later. At the necropsy were found tubercular arthritis of the wounded thumb and many vomicæ in the lungs.^[15]

The post-mortem wart (tuberculosis verrucosa cutis) is familiar to surgeons as occurring in butchers and tanners, and there is every presumption that in many cases this is of bovine origin (Martin du Magny, Hanot, Senn, Riehl, Paltauf, Osier). Gerber testifies that in exceptional cases this extends to the lymph-glands and becomes generalized.

Dr. Stang, of Amorbach, had a five-year-old, finely developed boy patient, of healthy parents, destitute of hereditary taint. He died after a few weeks’ illness with miliary tuberculosis of the lungs and enormously enlarged tubercular mesenteric glands. The cow which supplied his milk had been killed a short time before with pulmonary tuberculosis.^[16]

Dr. Demme, of the Children’s Hospital, Berne, had four infants, the offspring of sound parents, with no hereditary taint of tubercle, die of intestinal and mesenteric tuberculosis, having been fed on the milk of tuberculous cows. Among 2,000 tuberculous infants treated in twenty years these were the only ones in which he could exclude the probability of hereditary and other causes.^[17]

Mr. Howe, of North Hadley, Mass., lost a son, aged twenty months, from abdominal tuberculosis, three months after he had paid a week’s visit to his uncle and had been fed the milk of the uncle’s tuberculous cow. The cow showed at death generalized tuberculosis. The child had been strong and well, as were his parents.

The four-year-old son of Colonel Beecher, of Yonkers, died March, 1894, of tubercular meningitis, and the two Alderney cows which had supplied him with milk were then proved consumptive by the tuberculin test and post-mortem examination.^[18]

The child of Dr. Brown, U. S. A., and now of Cornell University Medical School, was similarly cut off by tuberculosis, having been fed on the milk of a tuberculous cow.

Dr. C. H. Peabody had a child patient die of tubercular meningitis three months after the family cow had been killed for generalized tuberculosis. There had been previously no tuberculosis in the family (Ernst, Infectiousness of Milk).

A. H. Rose, of Littleton, Mass., gives the case of a child which was fed for three years on the milk of a tuberculous cow and died with abdominal tuberculosis (Ernst).

Gordon, of Quincy, Mass., records the case of a ten months old child of healthy parents and ancestry which had been fed on the milk of a cow with advanced tuberculosis, and which died after a few weeks with acute tuberculosis (Ernst).

Gage, of Lowell, Mass., had an infant patient of healthy parents and surroundings, but which subsisted exclusively on a cow’s milk that contained bacilli and infected Guinea pigs. The child died of tubercular meningitis. A second child fed the same milk suffered in a similar way (Ernst).

Andersen, of Seeland, reports the death from tuberculosis of a six months old child which had fed on the milk of a cow having tuberculosis of the udder. The mother developed symptoms of tuberculosis after the death of the child.^[19]

Dr. Gosse, of Geneva, Switzerland, spent his Sundays with his family on an estate in the hills, and his daughter, aged seventeen years, took great pleasure in drinking milk warm from the cows. Early in 1893 she sickened with an obscure illness, and after ten months died, revealing at the necropsy intestinal and mesenteric tuberculosis. The five cows on the estate were tested with tuberculin; four reacted and were killed; two showed tuberculous udders (Nocard).

Dr. H. M. Pond reports four cases of tuberculosis in one family, three of them fatal. The cows supplying the family with milk were tuberculous.^[20]

Dr. Faust, veterinarian, of Poughkeepsie, records the case of a family on Long Island that lost from tuberculosis 139 cows. A three-year-old child and two grown sons died of tuberculosis. Tuberculosis was unknown in the parents’ families.^[21]

Dr. Kelly, veterinarian, Albany, gives the following: In a family of five a son, aged nineteen years, was very fond of milk and drank it fresh from the cow, and contracted tuberculosis. Some months later the farm herd of seventeen registered Jerseys were tested with tuberculin, and thirteen reacted and showed extensive tuberculosis when killed.

Dr. Cooper, veterinarian, Paterson, N. J., furnishes this: A child, fed on the milk of a cow, contracted tabes mesenterica. Examination revealed the presence of tubercle bacilli in the milk. The milk was then fed to ten kittens, all of which became ill and emaciated, and when killed showed tuberculosis.

Such cases, in connection with the experimental inoculations, furnish more than mere circumstantial evidence. They are corroborated and strengthened by the very uniform diffusion of tuberculosis in man and stalled cattle in practically all civilized countries. Of the closer connection in individual cases one or two instances may here be added as drawn from personal observation:

1. In one case a family cow and the owner’s wife had both advanced tuberculosis. The lady consumed a good deal of the cow’s milk, but when she gave up its use she felt decidedly better.

2. The owner of a thoroughbred herd of sixty head had suffered for years from consumption, and attributed the poor condition of the animals to lack of care since he had been laid aside. Without the tuberculin test, I diagnosed tuberculosis in fifty-nine of the animals.

3. In a second thoroughbred herd there never lacked one or two cases of advanced tuberculosis, two of the family suffered, and the eldest son, who was fond of milk and vegetable food, died of pulmonary tuberculosis.

4. A dairy of common cows had seventeen out of twenty-six destroyed for tuberculosis, and the farmer’s wife, father-in-law, and two brothers-in-law had shortly before died of consumption. The wife felt ill in the close house air, and with her father occupied herself much about the cattle.

5. A veterinary professor, who was meat inspector of the city abattoir, died a few years ago of tuberculosis, which he handled so constantly in his daily duties.

Stalker and Niles report that 5 persons, 20 to 30 years of age, of healthy ancestry, died of tuberculosis within two years, on a farm where 17 tuberculous cattle were found, and others had died in previous years, (Bull. Ia. Agr. Exp. Stat., 29).

Leonhardt reports the death from tuberculosis, abdominal and meningeal, of two children, fed on the milk of a tuberculous cow, (Rep. N. H. Bd. of Health, 1892).

Sontag reports the death by tuberculosis of a six months old child of healthy parents, that had been fed the milk of a tuberculous cow, (Rep. N. H. Board of Health, 1892).

Dr. E. Pearson quotes the following:

“A well known veterinarian wounded in the hand in opening a tuberculous cow, had a tumid, intractable sore, the tissues of which when excised showed tubercle bacilli.

A veterinarian, of Chester Co., Pa., in opening a tuberculous cow, cut his knuckle, which healed tardily, remained swollen and when excised, showed typical tubercular lesions including giant cells.”

He quotes from Hartzell the cases of two men wounded in cleaning cattle cars, both of whom had resulting tubercle, arrested in one case by excision, but in the other advanced to generalized tuberculosis and death.

Bang gives the following Danish cases:

A merchant having two chlorotic daughters secured a fine cow to feed them fresh milk. The cow was killed tuberculous and was replaced by another which also showed tuberculosis, this time affecting the udder. The girls died of tuberculosis at 16 and 18 years. Two younger children fed on the milk of sound cows grew up healthy.

A healthy cow became tubercular, after having been placed in the same stall in which another had died of tuberculosis. A child fed almost exclusively on the milk of these two cows died of tuberculosis.

A peasant at Silkeborg drank freely of milk freshly drawn. He died of tuberculosis, as did also a cow, and later in the same stable, a pig.

A peasant had an 11 year old cow with generalized tuberculosis, implicating the udder. The wife of the peasant, formerly healthy, became tuberculous shortly after the udder became affected and died at 45. A daughter who, like her mother, used the milk of this cow, died consumptive in the same year. The husband who drank beer, and not milk, remained well.

A physician fed his two children on the milk of his tubercular cow, and lost both from tuberculosis. Neither parents nor grand-parents were tuberculous. (L. Pearson in Bull. 75, Tuberculosis of Cattle).

Thorne had reports from twenty-two Ohio physicians to the effect that they had traced tuberculosis in their patients to the use of the milk of tuberculous cows, and thirty-three who believed they had reason to suspect the meat and milk supply as the source of cases of consumption. (Ohio Exp. Stat. Bull. 108).

To these may be added the cutaneous forms of tuberculosis (tuberculosis verrucosa cutis), which occur on the hands of persons (butchers, tanners, coachmen, cooks, etc.), who handle infected products of animals. These have been described by Riehl and Paltauf, Senn, and a number of surgeons and dermatologists and the relation of the occupation to the seat of the disease is conclusive as to the source of the infection. It is the exact counterpart of the verrucosa necrogenica of the hands of persons working in the dissecting rooms of medical schools, and the source of infection is equally well established in both cases.

A strong argument for the appreciable influence of the bovine bacillus upon man (acting directly or indirectly through the pig) is that the relative death rate of Jews from tuberculosis is materially less than that of other races. It is constantly claimed that orthodox Jews who eat only kosher (rabbi inspected) beef and no pork, suffer least of all the population from tuberculosis. Dr. Gerster, judging by the burial returns of the United Synagogue and the English Registrar General’s returns, concludes that only about half the relative proportion of Hebrews suffer from consumption as do other races in the same country. Some remarkable facts come out in the report of the Royal Commission on tuberculosis in England. In England and Wales the disease had decreased 39.1 per cent, in thirty-five years, but this decrease has been mainly in pulmonary cases, while the abdominal forms decreased only 8.5 per cent. Sir Richard Thorne, indeed says, that in children of the first year there had been an actual encrease of 27.7 per cent. Northrup and Still, on the contrary, present statistics showing that in children the pulmonary form of tuberculosis is the most common (Brit. Med. Jour. 1898). If in the face of this there has been a very material encrease of the abdominal form, coincident with the notorious encrease of the disease in dairy cows and of the bottle-feeding of infants, may we not enquire how much of this is due to the greater prevalence of bottle-feeding and the infected cow’s milk? It is not for a moment supposed that the majority of infections in children come from the cow. The question is whether this encrease in the minority is not in measure chargeable on the cow. The impaired nutrition resulting in some instances from the use of cow’s milk cannot well be charged with a marked encrease of cases in which the mesenteric tubercles point so directly to infection through the food. If it is held that the tubercle bacilli in the milk are harmless, we wait for evidence of the real cause of such encrease and localization.

The experiments of Adami show that tubercle is directly transmissible from man to ox though usually with decreased virulence. More recently, Ravenel using the bacillus derived from the mesenteric glands of a child, injected intravenously two tuberculin-tested calves, with 5cc. each of the culture producing exalted hyperthermia, miliary tuberculosis of the lungs, tuberculosis and caseation of the bronchial and mediastinal glands, and death in 17 days. Dr. Garnault’s experiment on himself, now in progress, has already shown the great danger to a susceptible man, of the bovine bacillus.

As showing accommodation to environment, Battaillon and Ferre found that the bacillus (mammalian and avian) grown in frogs, Dubard that grown in fishes, Kráhl that grown in frogs, snakes, fishes and lizards, and Müeller that grown in the glow worm, thereafter grew at summer temperature (68° F.) and grew poorly or not at all in the bodies of mammalia.

The tubercle bacillus is primarily and essentially one, but this must not close our eyes to the fact that in different hosts and environments it takes on very different habits, so that for the time and in these surroundings, it is materially modified in its pathogenic attitude toward different races. Yet its ready variability when conditions are favorable to change, renders it desirable to destroy it in all its forms, and especially in those which approximate most closely to those that prey on man and animals.

An impartial review of the whole field warrants the conclusion that the nineteen young (and therefore comparatively insusceptible) cattle which in Koch’s hands failed to develop generalized tuberculosis after inoculation with the virulent sputum of man, and the smaller numbers that resulted in the same way under similar treatment in the hands of Th. Smith, Dinwiddie and Adami, while showing a very marked limitation in the susceptibility of the sound bovine system to weak bacilli from man, cannot disprove the many well authenticated cases of the transmission of tuberculosis from cow to man and the reverse. The greater potency of the bovine bacillus over that of man, in its action on the small rodents and pigs, utterly forbids the unproved assumption that it is on the contrary harmless to man.

If the object of the sanitarian were merely to delay a fatal result in his tuberculous patient, while he accepted the prevalence of tuberculosis as inevitable for all future time, the acknowledged lessened receptivity of the ox for the bacillus from man would mean more and would be at least worthy of a hearing, but as the extinction of a disease germ and its representative plague must ever be the first object, any movement toward the preservation in cattle of a germ which is deadly to man and much more so to cattle, must be held as subversive of the prime purpose of sanitary work. This is true even if we allow, for the sake of argument, that only a few of the bovine bacilli are capable of dangerously colonizing the human body, and that special environment is needful to allow of such successful colonization. On the other hand the limited receptivity of the ox for the bacillus from man is the greatest encouragement to active work to exterminate tuberculosis from our herds. It is impossible to adopt in man the summary measures that are so successful in the speedy stamping out of the plagues of the lower animals, so that tuberculosis in the human family can only be eradicated by slow degrees, and therefore there will long continue for our herds the danger from the human side, but just so far as the susceptibility of cattle to human tuberculosis is limited, in the same ratio are our hands strengthened in effective work for the extinction of consumption in our herds and for preserving their soundness after they have once been purified. If they were to be reinfected by the presence of any consumptive person we might well despair of success in face of a wide prevalence of tuberculosis in man, but since it is only exceptionally that cattle suffer from man, outbreaks coming from this source can the more easily be taken care of. In this view tuberculosis is approximated somewhat more closely to the other bovine plagues (lung plague, rinderpest) which can be stamped out with the greatest ease and certainty, so that as a purely economic measure the argument for the speedy extinction of tuberculosis in our herds is reinforced.

TREATMENT OF TUBERCULOSIS.

Like all deadly infectious diseases in the lower animals, tuberculosis is not to be profitably treated as a rule. In the case of specially valuable breeding animals, in which the prospective progeny will pay for large outlay, and when the disease is in its incipient stage, treatment may be warranted. The patient should be thoroughly separated from other animals, kept in the open air, or, in our northern winters, in roomy, well ventilated buildings facing the south, well lighted, kept immaculately clean, frequently whitewashed, and well drained. If there are more than one case every precaution named under the head of prevention must be adopted. Exercise to keep the muscular system in good tone is called for, but never to fatigue. Hence, a sheltered pasturage is ideal. Feeding must be liberal including a ration of grain or seeds, and oil bearing seeds like linseed, rape seed or cotton seed may be specially named. Cod liver oil alone, or etherized is often of great value, with iron and bitters continued for weeks or months. In the case of specially valuable animals one may use a pneumatic cabinet the principle of which is to diminish the air pressure on the body at large by an exhaust, while pure air for breathing, at the ordinary atmospheric pressure, is introduced through a tube furnished with a face piece fitting around closely beneath the eyes. This serves the purpose of attracting (sucking) the blood toward the skin and other tissues from the lungs, which in their turn are compressed by the air at the atmospheric pressure. Pulmonary congestion is in this way lessened, exudates are absorbed, necrotic tissue removed, sepsis counteracted, hæmatosis encreased, circulation of both blood and lymph stimulated, digestion and nutrition improved, and general health invigorated.

Active grooming and even the stimulating effect of cold douches may be invoked, the skin being rubbed actively until dry and warm.

If the circulation is poor, a stimulating steam or hot water bath of fifteen minutes followed by a cold sponge and rubbing till dry may be profitably substituted. In such cases it is well to put a cold sponge on the head while in the bath.

Medicated inhalation is often valuable especially when the lesions are on, or near the bronchial mucosa. In 1868, Dewar met with most successful results from inhalation of sulphurous acid gas impregnating the atmosphere as strongly as the patient can breath without discomfort. His own groom who had given up work because of advanced phthisis, under treatment of half an hour three times a day, became ruddy, gained weight, and betook himself to work again. In rabbits which I inoculated with human sputa, the same year, all died tuberculous excepting one which I fumigated three times a day for weeks. This rabbit remained plump and well.

As an example of a still more irritating inhalant, I watched the case of a phthisical man who secured employment on the government disinfecting corps, in Chicago, in purifying the lung-plague-infected stables with chloride of lime solution, and who very soon began to improve, gaining weight and strength, his cough meanwhile subsiding.

Cervello’s use of formalina by inhalation though well spoken of by its inventor would seem too irritating on the delicate lungs, however good it is as an antiseptic.

Inhalants may be conjoined with the pneumatic cabinet.

Among agents used to moderate the cough may be named codeine, morphia, cherry laurel water, wild cherry bark, guaiacol, menthol, syrup of Tolu, or chloroform, or alcohol inhalation.

As an internal antiseptic, carbonate of creosote has often proved beneficial.

Mustard blisters on the skin covering the tubercle is claimed by Knopf to act beneficially by attracting the microbes from the delicate lungs to the more robust skin and connective tissue, where they can be better disposed of by the more abundant leucocytes.

He has also found excellent results in complex infections in animals from the use of Marmorek’s streptococcic serum in doses of 10cc., followed after the second dose by 5cc. every 24 hours. In other cases it failed of the effect (reduction to normal temperature) evidently indicating that the hyperthermia was maintained by other microbes than the streptococcus. The principle is good, and perhaps at some time in the future a bacteriological examination of the sputum may reveal the microbes present and suggest the sera for such complications.

The introduction of air into the peritoneum has long been known to exercise a retarding and curative action on abdominal tuberculosis. At the present writing my colleague, V. A. Moore, is experimenting by pumping air and oxygen into the peritoneum and pleuræ in cattle slightly affected, with encouraging results.

I should add that isolated superficial tubercles may often be excised to advantage, and the part dressed antiseptically.

It is only in exceptional cases, however, that one is warranted in preserving and running the danger of spreading the tubercle bacillus for the advantage that can be secured to individual animals from treatment.

EXTINCTION OF TUBERCULOSIS IN CATTLE.

As cattle are the great propagators of tuberculosis on the farm, the question of extinction necessarily centres around this race. As in all other dangerous infections, the most prompt and successful method would be in the time honored one of destroying the infected and thoroughly disinfecting all their products. The only barrier to success in such a case would be the conveyance of infection anew from man to cattle after the herd had been purified. The demonstration that cattle are less susceptible to infection by the human sputa than many had supposed does away largely with this objection, as in a generally purified bovine race, the few primary cases contracted from man could be easily taken care of. Then, if tuberculous persons were interdicted from attendance on cattle, the danger in this direction would become very nearly a negligible quantity.

There remains the question of expense and many honestly consider this as absolutely prohibitory. The estimate of 5 per cent. of our 68,000,000 head to be killed and paid for at $25 per head, would be $85,000,000. But there is no necessity for this. Our fat steers at the packing houses are tuberculous only to the extent of 0.02 per cent., speaking well for their dams and nurses. The estimate of 5 per cent., based upon the testing of those few herds that have been taken because they were already known to be tuberculous, is unquestionably far above the actual ratio for the United States. It may apply to dairy cattle in some infected districts, but, for the bovine race of the whole country, it is absurdly high. If we had 10, 20 or 50 per cent. infected, as in some countries of Europe, the objection of expense might be a formidable one, but when the ratio of the infected is but 2:10000, we have every encouragement on the score of expense to enter on a campaign of extinction. But again, we do not need to deal with 68,000,000 cattle as we can omit the steers which are so little affected and which will all come to the slaughter house in two or three years. The source of their infection (a few cases excepted) is in the older cows and bulls of the dairy and breeding herds, and this brings down our total to a little over 17,000,000. The average census price for dairy cows is $29 and, as the condemned cows are depreciated by their condition, it would be a high average to estimate them at $20. Again, the average infected ratio of cows for the entire country would be set high at 2 per cent., and on this basis it might well be that the required indemnity would not aggregate much over $6,000,000. Five or even ten times that amount would be a mere trifle in comparison with the $3,000,000,000 value, constantly encreasing, of our domestic animals, with the $99,210,272, representing our yearly product of beef and beef products, with our annual dairy products, worth $500,000,000, (Alford), or with our yearly loss of 100,000 of our population in the very prime of life when they are of the greatest value to the country, representing a yearly drain of $100,000,000, beside all the suffering and loss entailed by their prolonged and too often helpless idleness. Though this last item is doomed to continue for a length of time after the disease has been extinguished in our herds, it is receiving constant accessions from the latter, and can never be entirely done away with until our cattle are above suspicion.

An even more serious problem is the demand for tuberculin and above all for accomplished, experienced and honorable veterinarians fitted to conduct the sanitary campaign over the entire country. The tuberculin cannot be produced in a week or a month, yet the problem of its production in any required amount in a few months is merely one of the encrease of existing plants under the management of the same careful hands now engaged upon it. As to veterinarians it would be impossible to secure at once the required staff of men capable of carrying out the work over the whole country. But this is not essential. The work can be begun in the counties supplying the large cities with milk, and in the great butter and cheese producing areas where it is so urgently needed, and it must be made to include all thoroughbred herds, which are so constantly drawn upon to improve the blood elsewhere, and each herd, county and district, as freed from infection must be scheduled and no additions made to it from outside, except under the guarantee of the tuberculin test, repeated in six months. The reacting animals, must be appraised, excluded from the herd, and disposed of, it may be to the butcher to be killed under official expert inspection, and the salvage, if any, to be deducted from the appraised value; or to be rendered and the salvage estimated; or to be buried as the case may be. In all such cases the other animals (horses, pigs) that occupy the same buildings and yards should be tested, although the risk of the infection of cattle from these animals is comparatively small. Unless in badly infected herds, steers and young cattle, which can be kept in a separate herd need not be tested. Vermin must be killed. Thorough disinfection must be applied to buildings and yards, and the dairy herd must be retested at the end of every six months until no more reactions are met with.

In this way the campaign in any State can be begun with a small staff, which may be steadily encreased as men are trained to the work, and in no great length of time the dairying and breeding herds can be purified and the investigation carried into the more purely agricultural fields, where herds are small and usually free from infection. Many minor points would require the attention of a competent superintendent of the work. My object here is to make a plea for the approved and attested method which has never failed in the case of other animal infections on enclosed farms, and which is based on the absolute destruction of every seed of the disease in the area under sanitary control. The method has the apparent drawback, that it demands a greater relative outlay at the start, than do others proposed, but in view of its certainty, and the confident hope of an early abolition of all infection, loss, and expensive expert control, it must, in my opinion, be looked upon here, as it has always proved in the past, the course of the truest economy. It may be compared to the treatment of a field of thistles by removing the offensive weeds, root and branch, before they have advanced to seed, instead of merely cutting them down with a mower, and leaving the roots, to grow anew, to leaf, to blossom and seed, in spite of the temporary partial drawback. But as the prospect of early legislation along this line is not a bright one, the expert must accommodate his aims and efforts to what can be done under the existing laws.

Breeding Healthy Stock from Parents with Latent Tuberculosis. When a State is not pledged to exterminate tuberculosis by prompt and radical measures, it is quite possible to raise healthy stock from sires and dams that have the disease in a latent form. It is very exceptional that calves are born tuberculous. If, then, they are kept in a pure environment and furnished with the milk of sound nurses, or even with the milk of their own tuberculous dams, after it has been heated for one-quarter of an hour to 180° F. or 212° F. they can be preserved in perfect health.

This is especially adapted to herds of valuable thoroughbreds, the destruction of which would be a serious loss, and the preservation of the strain of blood a most desirable object.

The whole herd should be tested with tuberculin, and the advanced and generalized cases, that can be detected by objective symptoms, should be at once destroyed and safely disposed of. The animals in good condition and that have not reacted should be placed in a new barn and yard, or where no tubercle has been, or in places that have been thoroughly disinfected, under special attendants. There will remain the animals in good condition with no objective symptom, but that have reacted, and these are placed in separate barn, yard and pasture well away from other stock, under their own attendants, for breeding purposes. They should have the best of food and air, clean, well lighted, roomy buildings with shelter from storms, clean sheltered yards, and in summer, pasturage. Any cow showing indication of active advance or generalization of the disease (cough, wheezing, dyspnœa under exertion, excessive pallor of mucosæ, unthriftiness) should be at once separated and destroyed as endangering the reinfection of others, and the stable subjected to disinfection. The calf, as soon as born, must be removed to a special building or park, where it shall get milk from a sound cow or that of its own dam after it has been carefully sterilized. After sterilization the milk cannot safely be returned to the unscalded pail into which it was drawn from the cow, and it should be fed by separate attendants who have not milked nor handled the affected animal. Any loss of condition, unthriftiness, cough or scouring on the part of any of the calves should be the signal for its separation from its fellows, subjection to the tuberculin test, and, if it reacts, for its destruction and the disinfection of the building where it was. It is well to test each calf at six weeks old and to remove the reacting ones. The success of this method is now well established.

Goodman, of Dorpat, applied it largely as early as 1891, rearing the healthy calves of reacting cows on the milk of cows that had stood the test. Bang, of Denmark, raised such calves to sound maturity on sterilized milk. Reynolds, of Minnesota, reports the raising of twenty-four healthy calves from infected cows on the milk of tested cows, while three fed on milk of reacting cows, which was supposed to be sterilized, all became tuberculous. McEachran (1899) in an extended experiment succeeded perfectly with the milk of tested cows only. I have now in hand a Jersey herd in which the progeny, fed on the milk of their reacting dams, became tuberculous without exception, and in the years following, those fed on the milk of the same reacting cows after it had been kept at 180° F. for half an hour all grew up healthy.

Under this method, inasmuch as the infection is not at once extinguished, but temporized with for the benefit of the stock owner, State indemnities are not necessarily called for. Yet the State can profitably test the cattle at public expense, mark indelibly those that react, schedule them and control them, so that they will not be allowed to change hands nor to mingle with sound animals until finally butchered, dead or recovered. The State should see to the thoroughness of the seclusion, disinfection, the safe disposal of all products from milk to manure, and the testing at intervals of three or six months of both cows and calves.

Raising Healthy Offspring Without Sterilizing the Milk. In the northwest territories cows and heifers that have reacted to tuberculin, but which otherwise appear to be in good health, are made into a herd by themselves and placed on a special range apart from all other cattle. They live in the open air, slight shelter being allowed in winter only, and their calves are allowed to suck the dams until winter. The wide range, the open air life, and the early destruction by oxygen and sunshine of the discharged bacilli, tend in the main to ward off infection, except such as comes in the milk, and the majority of the calves grow up in apparent health and are fattened for market. A small minority are born tuberculous or contract the infection from the milk, but this does not seriously impair the financial success, and living in the open air they bring little danger to others. The loss is infinitesimal as compared with the expense of milking a large herd, sterilizing the milk and feeding it by hand. Advanced cases, with objective symptoms, should always be removed, and the cows may be tested at intervals if compatible with profit. The seclusion of the herd should be complete, by distance, by the configuration of the country, or by fence.

For this system the climate of our Southern States, where stock can remain out of doors all the year, offers a better field than the semi-arctic northwest.

Removal of all Unthrifty Animals and Those Showing Physical Symptoms of Tuberculosis. Before the days of tuberculin testing I succeeded in extinguishing tuberculosis in several herds by the prompt removal of all unthrifty animals and such as showed objective symptoms of tuberculosis, the disinfection of the buildings, the restocking from sound herds, and the strict separation of the new stock from the old. In one herd of 200 this entailed the final destruction of the whole original herd; in others the destruction was in the main limited to particular (susceptible) families. But in these days, with the tuberculin test available, a resort to a method of this kind would produce an unnecessarily slow, uncertain and expensive result.

Removal of Animals Showing Objective Symptoms or Reaction under Tuberculin. The Bang (Danish) method is the chief example of this, and is so considerate of both state outlay and stock owner’s interests that it is deserving of high praise. Under it the State usually waits for the stock owner to take the initiative, but to encourage applications from the owners, it furnishes tuberculin testing without expense, and even allows a small indemnity for animals killed because of advanced tuberculosis. In return for this the stock owner agrees to furnish separate buildings (or enclosures), yards and pasturages, new or, when necessary, disinfected, one set for the high conditioned, nonreacting, healthy herd, and a second for the animals that reacted but which show no further sign of tuberculosis, with separate attendants, utensils and other appointments for each. This reacting herd is furnished with the best of food, air, accommodation and hygiene generally, and the milk is sterilized before it is allowed to pass into consumption by man or for calves or pigs or for the production of butter. The quarantined herd is marked, registered, and kept under government surveillance; it cannot be parted with for stock uses, but it is at the disposal of the owner to keep it for milk, or fatten at once for the butcher. Finally every member of this herd is slaughtered under government inspection, and the beef put on the market or sent to the rendering works as may be decided. The system secures the hearty coöperation of dairyman, dealer and government, and while it comes short of the speed and efficiency of a generally applied method of extinction, it is accomplishing a great work for Denmark, putting an immediate stop to the advance of the disease in the worst infected herds, and placing the latent cases of such herds in a safe seclusion for the rest of their lives. At first the tested herds showed 40 per cent. affected; now less than 20 per cent.

The feature which would be likely to work the least satisfactorily in the United States, is the disposal of the sterilized milk as such. It is to be feared that this milk would find but a poor market with us, and if it proved unsalable, the preservation of the reacting herd would be no longer an economic success.

In Pennsylvania where practically the same method is in force, leaving it in the option of the owner to keep the reacting latent cases and sterilize their milk, or to abandon them to the State, have them appraised and slaughtered with indemnity, the uniform practice has been to accept the latter alternative. Not a single owner, I believe, has elected to keep a herd in quarantine and sell the milk sterilized. The result has been that four times the number of applications come in that the appropriation will warrant the officials to take in hand.

A special feature of the Pennsylvania method is the provision that a stockowner can have his herd examined, and tested with tuberculin, at his expense, the State to furnish a certificate setting forth the condition of the animals. In case of infection, the owner has the option of abandoning the reacting ones to the State, to be secluded, or appraised and slaughtered, he meanwhile guaranteeing that he shall introduce no new animals into the herd except by tuberculin test under the direction of the State Board.

The usual provision is in force that no indemnity is allowed for any animal that entered the state not more than three months before, and without the tuberculin test demanded of all such stock animals.

Indemnities are restricted to $25 per head and under for non-registered animals and grades, and $50 for registered thoroughbreds. The average appraised price has been $23.

On the whole an excellent work is being done in Pennsylvania, and herds now tested are found to contain not more than half as many infected animals as did those tested a few years ago. A better showing would doubtless have been made if the State appropriation had permitted the board to give attention to all applications made.

The good results may be attributed to the adoption of a system which secured the confidence and trust of the stockowner: he sees that the State has no desire to oppress nor injure him; he is in no dread of a high-handed confiscation of his remunerative property without indemnity; while advanced cases are destroyed he is left the option of segregating his latent cases and marketing their products under the precaution of sterilization; he can raise the progeny of these animals if he will, under similar precautions; he can sell his stock and its product under government certificate if they prove sound; he can avail of government assistance in protecting his herd against reinfection, by the testing of animals to be purchased. Under such a system there is no object in secreting infection, and in underhanded sale of tuberculous animals, with the spread of the disease into new centres. Even the tardy or inimical stockowner is roused to action by public opinion, when he finds the market for his suspected product growing more and more uncertain, and feels the daily encreasing pressure of opinion among neighboring owners, that he is exceeding his rights in maintaining an infected herd in the very midst of their purified ones.

A most important item of the system of Pennsylvania, and of sixteen other states, is the compulsory testing of all stock cattle introduced into the State. This has the further support of the Federal Government which demands a tuberculin test of every stock bovine animal imported into the United States. This is a natural corollary of every attempt to restrict or extirpate tuberculosis from a State, but when through willful blindness a great State like New York, repudiates a measure of this kind, it but makes its dairy and breeding herds the depository of the reacting animals that other states wisely exclude. The sifting process goes on at Buffalo and other centres and the New York herds are loaded with the rejected, diseased animals. Under the operation of this, and the denial of indemnity for animals slaughtered, it will be wonderful, if the New York stock owner is not soon roused up from his idle dream of fancied security, by a great extension of the infection.

Generally Applicable Measures. Under any system many special rules will be demanded in individual cases, which it will require the skill of the expert sanitarian to apply, and which cannot be referred to here. The following are generally applicable whether by the owner in his particular herd, or by the State or other authority dealing with the subject.

1st. On discovery of a case of tuberculosis, test the whole herd with tuberculin. (See Tuberculin Testing.)

2d. Remove all animals that show a typical reaction.

3d. Destroy and burn, boil or deeply bury all cases of the disease, unless it is decided to form an isolated herd of latent cases which are in good condition and apparent good health.

4th. In case of doubt or disturbing influence which may have caused rise of temperature (calving, heat, exposure, concurrent disease, changes in management, etc.), keep the suspected animal apart for four weeks and test again.

5th. Repeat the test every six months, and if two successive tests show no indication of tuberculosis, the herd may be accounted sound.

6th. As soon as tuberculous animals have been removed from a stable, let it be vacated and thoroughly disinfected with chloride of lime, 4 ozs. to 1 gallon of water, and enough quick lime to make a good whitewash which will show if even a square inch is missed. When chloride of lime is objectionable because of its tainting the milk, use mercuric chloride 1 dr. to 1 gallon water, with enough sal ammoniac to make it freely soluble. The roof, walls, and especially the floor, gutter and feeding trough must be first thoroughly scraped, washed and cleaned, all rotten wood work must be removed, and, in case of double boarded walls, the boards must be removed on one side to permit of a thorough application. Utensils should be scalded and dressed with carbolic acid, 1:20. A stable incapable of disinfection should be abandoned for a length of time or burned.

7th. In making new purchases, avoid any herd in which tuberculosis has appeared, or that has had sickness or deaths in recent years.

8th. Do not purchase from city, suburban nor swill stables.

9th. Do not take a cow that is in ill health or low condition, especially one with cough, nasal discharge, foul breath, wheezing breathing, hard nodules under the skin, diseased udder, swollen bones or joints, or a tendency to scour or bloat.

10th. Test every animal with tuberculin before admitting it into the herd.

11th. Do not admit strange cattle to house, field or yard. Keep apart from the herd until tested.

12th. Keep each animal strictly to its own stall and manger.

13th. Board up between the stalls in front so that no two cows can feed from the same manger.

14th. Be especially watchful of the older cows and on the slightest sign of ill health, separate and subject to the tuberculin test.

15th. In case a herd of cattle is found to be tuberculous, subject to the tuberculin test all domestic animals that have mingled with them freely and fed from the same troughs. Remove those that show a reaction.

16th. Exterminate the vermin (rats, mice, sparrows) in a building where tuberculosis has prevailed.

17th. Let no consumptive person attend on cattle nor prepare their food.