TUBERCULOSIS.

Synonyms. Definition: infectious disease caused by bacillus, attended

by productive inflammation, tubercles, necrotic degeneration,

caseation, fibroid change, calcification or ulceration. Animals

susceptible: python, salamander, carp, fish, birds, rodents, sheep,

goats, solipeds, cattle, dogs, cats, apes, swine, wild ruminants,

kangaroo, carnivora, cage birds, civilized (housed) man. Geographical

distribution: with dense population, Central Europe, Britain, Eastern

States; little in absence of cattle products—Scottish Western Isles,

Iceland, Newfoundland, Greenland Highlands, Arctic North America,

Northern Norway, Sweden, Lapland: open air life protects. Virulence:

ancient records, modern, early antituberculous legislation, decimation

of herds, researches of Vilemin, Gerlach, Chauveau, Semmer, Parrot,

Tappeiner, etc. Bacillus tuberculosis: evolutionary changes, relation

to actinomyces, 1.5 to 3.5μ by 0.2μ shorter and thicker in ox,

solitary, exceptionally short chains, on blood serum may be

filamentous, staining slow, carbolated fuchsin, technique, sections;

biology, adaptation to environment, to genera, variation in same

genus, experiments showing real identity of variant forms; vitality:

in water human bacillus 50 to 70 days, bovine bacillus indefinitely,

avian 117 days, dried sputa 9 months, cow’s lung 102 days, putrid

material 43 days to years, survives gastric juice, sunlight kills in

some hours, if in thin layer, day light 7 to 18 days, dry heat (212°

F.) for an hour left living bacilli, moist heat 140° F. for 1 hour

kills, low temperatures (−25° F.) fail, after 15 days in salt failed

in rabbit, after 30 in Guinea pig. Chemical disinfectants. Accessory

causes: racial vulnerability, close buildings, dark, foul, damp

stables, poor scanty food, heavy milking, conformation, early

breeding, inbreeding, age, predisposing diseases, traffic in animals,

dairy extension, admission of tuberculous animals from other states,

assorting tuberculous for sale in a given State, sale of sound from

tuberculous herd, lack of indemnity for animals killed, private

testing of herds and sale of tuberculous, accustoming to tuberculin

test, antipyretics during tuberculin test, false certificates of

tuberculin tests, feeding hogs on tuberculous offal, feeding calves

and hogs on tuberculous milk, feeding hogs after tuberculous cattle,

feeding from a common trough, dry, dusty stables, extension through

vermin, flies and other insects carry virus. The tubercle: miliary,

pinhead, conglomerate, proliferation of cells—tissue and leucocytes,

in nests in stroma, giant cells in center, then epithelioid, then

lymphoid, caseation, calcification, fibrosis, pearl disease.

Localization: _Cattle_: pulmonary: miliary tuberculosis, aggregation

into larger tubercles, caseated centres, fibroid, cretified,

abscesses, vomicæ, complex infections, infiltrations, difference from

broncho-pneumonia, lesions of different ages; pleural lesions;

congestion, exudation, fringes, nodules, grapes, adhesions,

caseations: bronchial and mediastinal glands, congestion, swelling,

softening, induration, caseation, cretefaction: cardiac lesions:

lesions of mouth and throat, pharyngeal glands: gastro-intestinal,

peritoneal, mesenteric glandular; œsophagastoma; liver tubercle;

splenic; pancreatic; genito-urinary; mammary; cerebral; spinal;

orbital; skeletal; cutaneous; muscular; glandular; table of

distribution. _Swine_: lesions: pharyngeal, intestinal, mesenteric,

muscular, hepatic, splenic, glandular, pulmonary, skeletal, caseation,

liquefaction. _Horse_: lesions: thoracic, abdominal, glandular, of

serosæ, vertebræ, etc. _Sheep_ and goat: lesions: thoracic, abdominal,

glandular, hepatic, pharyngeal, facial, etc., verminous affections.

_Dog and Cat_: lesions: respiratory, abdominal, pharyngeal, tonsillar,

hepatic, pancreatic, splenic, skeletal, arthritic, cutaneous. _Apes

and Menagerie Animals_: lesions. _Chickens_: lesions: intestines,

liver, spleen, peritoneum: lungs and kidneys often escape. _Pheasant_:

lesions: as in hens, centre zone has epithelioid cells, fibroid,

cretefaction, amyloid degeneration. _Parrot_: lesions: eye, beak,

tongue, palate, larynx, bones, joints, lungs, liver, intestines,

muscles, skin. Primary and secondary infection, extension by

lymphatics, blood channels, tonsils, inhalation, deglutition.

_Synonyms._ Consumption; Tabes; Scrofula; Pining; Grapes; Great White

Plague, etc.

_Definition._ An infectious disease common to man and a large number of

animals, caused by the bacillus tuberculosis, and characterized by a

productive inflammation giving rise to small, rounded bodies

(tubercles), or diffuse infiltration, with a tendency to necrotic

degeneration, and caseation, or to fibroid degeneration (sclerosis),

calcification or ulceration.

_Animals susceptible._ Tuberculosis comes near to being a panzoötic,

since although reptiles, fishes, birds and some mammals do not readily

contract it under normal conditions, yet under abnormal and debilitating

conditions nearly all will succumb to it.

_Reptiles._ Sutton found tuberculosis in a python which was kept so warm

in the London Zoological Gardens that a thermometer between its folds

registered 85° F. Kráhl, Battaillon and Ferre cultivated the bacillus in

frogs, Kráhl in snakes. Blauvelt found tuberculosis in a salamander.

Lechner found it in amphibia.

_Fishes._ Broussais records the prevalence of tuberculosis in carp in a

pond which received the sputa of a consumptive man. Under the skin were

found rounded tumors, containing abundance of bacilli, that infected

rabbits and Guinea pigs on which they were inoculated.

_Birds._ In birds of the farmyard—hens, pheasants, turkeys, ducks and

pigeons—it is very frequent and often occurs as an epizoötic. While the

tuberculosis of barnyard fowl is a manifest variety and not readily

interchangeable with the varieties affecting the mammal, yet, with a

special predisposition, it can be transferred and can then be conveyed

from animal to animal in the new genus in which it has been implanted.

That of cage birds is interchangeable with that of man.

_Rodents._ Guinea pigs have a strong susceptibility to tuberculosis,

whether from human or bovine source, and rabbits for that of birds, and

by continuous transmission through the body of the rodent, all alike

seem to tend toward acquiring common characters. The Guinea-pig,

therefore, has been especially availed of for the experimental

transmission of tuberculosis, and, as the disease in them becomes acute

and rapid in its progress, these subjects permit the multiplying of

experiments in a short period. _Rabbits_ are less vulnerable to the

bovine or human form.

_Sheep and goats_, kept under usual conditions, show a remarkable

immunity from tuberculosis, yet if directly inoculated an inherent

susceptibility is easily shown. Habitual immunity may be in some degree

due to their open air life, to the heavy winter fleece protecting them

against chills, to the comparative absence of the heavy and continuous

milk yield demanded of cows, to the more restricted development of the

lymph plexuses in the lungs and elsewhere, and to the limited

opportunity offered by the small tonsils for infection entrance.

The _horse, ass and mule_ rarely contract tuberculosis casually, the

more spacious stall, outdoor life, hard muscular condition, the very

small tonsils, the exclusive nasal respiration, the paucity of

connective tissue lymph plexuses, and the abundance of red globules,

probably favor immunity. Yet on inoculation by Chauveau, Nocard and

others, the horse readily succumbed to infection, generalization taking

place more certainly than in the ox.

_Cattle._ The bovine races are remarkably subject to tuberculosis. This

is probably due in part to the great amount of connective tissue lymph

plexus in the lungs and elsewhere, the habit of using the mouth in

hurried breathing, the deep, sudden inspiration through the mouth and

over the tonsils that follows a cough, the habitual restricted size of

the cow stables, the absence of individual separated stalls, the habit

of feeding from the same trough with the cattle adjacent, the great

drain of yearly breeding and heavy milking, the retention in the herd of

old, failing cows for their milk product and high priced offspring, and

the bovine habit of licking each other with the infected tongue. In many

European cities and even in country districts the disease is very

prevalent. In Copenhagen a few years ago 17.7 per cent. of all oxen and

cows killed in the abattoirs were tuberculous; in Berlin 15 per cent.;

in Holland 20 per cent.; in Pomerania and Bomberg 50 per cent.; in

Hildesheim, Hanover, 50 per cent.; in Berlin dairies 75 per cent.

(Ostertag): in Leipsic and Edinburgh 20 per cent. The great variation in

the data for the different cities is suggestive of different inspection

standards. American figures as given by the Bureau of Animal Industry

are for Baltimore (mostly cows recently from the country) 2.5 to 3.5 per

cent.; and for the packing centers (among 2,273,547 mostly fat steers,

and therefore selected) 0.02 per cent. It is here largely a matter of

locality and infection, I have seen large herds with 100 per cent.

tuberculous, and extensive districts, in the north and especially in the

south entirely free from the disease.

_Dogs and cats_ in their natural condition rarely show the disease, but

contract it readily on inoculation. Cadiot found 40 cases in 9,000 _post

mortems_ of dogs. The young are apparently more susceptible than the

old, and primary lesions in the abdomen are common and suggest infection

through the food. The majority belonged to consumptive persons, and

gnawed the bones that had been first picked by the owner, and ate from

his plate what he left. Jacobi records the case of a dog, with general

tuberculosis, which habitually licked up the expectorations of his

phthisical master.

_Apes and Monkeys_, in confinement, almost all die of tuberculosis.

_Swine_ contract tuberculosis readily, the large tonsils, the habit of

breathing through the mouth, and the abundance of connective tissue and

lymph plexuses in the lungs and elsewhere contributing to this. Yet in

them the affection is mainly a dietetic disease. Swine kept in the

country and fed on vegetable food are rarely affected. In Saxony, where

17 per cent. of the cattle are tuberculous only a shade over one per

cent. of swine were so, and in Baden only 0.02 per cent. In hogs raised

on our western farms and corn-fed the proportion is much less. Yet in

those fed on uncooked skim milk, kitchen scraps and the refuse of

slaughterhouses in a raw state, tuberculosis becomes very common. In one

case, in a large public institution, where the dairy herd was

universally affected, and where, on their slaughter, their raw offal had

been thrown to the hogs, I found that the latter were almost all

tuberculous. Similarly, in feeding experiments, from the time of

Gerlach, pigs and especially young pigs, have shown themselves to be

very susceptible.

Among the less domesticated animals that contract tuberculosis may be

named _deer_, _elk_, _gazelle_, _antelope_, _camel_, _dromedary_,

_giraffe_, _kangaroo_, _lion_, _tiger_, _jackal_, _jaguar_, _bear_,

_arctic fox_, _rat_, _mouse_ and the _common cage birds_, etc. Fröhner

found 36 per cent. of parrots affected in Berlin.

_Man_ has long been recognized as standing in the front rank of

susceptibility to tuberculosis. Yet even in his case the prevalence of

the affection bears an intimate relation to his indoor life. In large

cities _post mortems_ often show that one-third have suffered, and that

one-seventh and upward of the whole population die of tuberculosis.

Natives of tropical islands and countries, living in the open air and

apart from close association with civilized man, often escape entirely.

In South Africa the herdsmen living in close buildings suffer

encreasingly, while their cattle, kept constantly in the open pasture,

escape.

_Geographical Distribution._ The prevalence of tuberculosis shows a

direct relation to the opportunity for infection rather than to climate,

latitude or altitude. It is the prevailing disease of civilized

communities with dense populations, and especially in large cities where

the general vitality is lowered and the crowded buildings give every

opportunity for infection. It is preëminently the disease of Central

Europe, of Great Britain and of our Eastern States, where there is the

greatest activity in business, manufacture and commerce. Yet in the

Scottish Hebrides, Iceland, Newfoundland, the Greenland Highlands,

Arctic North America, the northern parts of Norway and Sweden, Lapland

and Finland it is hardly known. The absence of commerce and cattle and

the sparse population have much to do with this. The coasts of Greenland

with their Danish stations have two-thirds of the population tuberculous

(Cook); the Indians of Barrow’s Straits, when infected in 1899 by the

frozen-in whalers, suffered from it as from a plague; in Christiana,

Stockholm and St. Petersburg it is as prevalent as in the large cities

of Central Europe. Elevated and dry climates have often been found to be

free from the affection, yet it prevails inside the double windows of

houses in the higher Alps, and has, within a generation established a

notorious prevalence in Minnesota, Dakota and westward, as it has in

Australia, mainly owing to the advent of consumptives who sought for

health in the dry atmosphere. The hills and dry tablelands in North and

South America, Africa and Asia which have acquired a reputation for

salubrity, owe this largely to the sparse population and the absence of

facilities for infection. In South Africa, in spite of the dry and

genial climate, the disease is constantly encreasing in the human

(housed) population. The sea-coasts, which are the seats of large cities

and the centres of population and trade, are also the most extensively

affected with tuberculosis—in the West Indian Islands, Panama,

Nicaragua, Mexico, Yucatan, Columbia, Equador, Peru, Chili, Ceylon,

Guinea coast—while the sparsely peopled highlands of the same countries

are practically free.

What is true of man is equally so of cattle. In the Gulf states of this

country, herds living in the open air are practically free from

tuberculosis, while in New Orleans and other large cities, the cows shut

up in the confined stables and yards, are as tuberculous as those of the

great cities of the north. So in many districts in the northern states

we find no bovine tuberculosis, while in others, differing in no

essential particular as regards geological formation, altitude,

exposure, and industrial use of the animal, a large proportion are

affected.

_Virulence._ Tuberculosis has long been recognized as virulent. “It is

indicated in the Mishna and other Jewish works as rendering the meat

unfit for consumption, but to come to more modern times, we find that

throughout the seventeenth and eighteenth centuries the flesh of

tuberculous animals was excluded from human food, alike by the civil and

ecclesiastical laws of Europe. Tuberculosis in cattle was erroneously

identified with syphilis of man, which made a frightful extension in the

end of the fifteenth century, spreading from the army of Charles VIII

which had been engaged in the siege of Naples. This conviction lasted

until it was disproved about 1782. Though mistaken in the identity of

the two diseases, the fact that for centuries the common people and

physicians both associated tuberculosis with a malady so notoriously

contagious as syphilis, speaks strongly for the forcible evidence of

contagion manifested at that time. Morgagni, who must have begun

practice about 1700 A. D., testifies to the strong conviction of the

contagious element in tuberculosis. Indeed it became a common practice

to isolate the consumptive person from the public, and after his death

to burn his clothes and sometimes even the house, or at least to subject

them to a careful disinfection. It is recorded that in 1750, in Nancy,

the magistrates ordered the burning, in the public square, of the

personal property of a woman who had died of phthisis, from sleeping in

the bed of another consumptive person.

“At Naples, a royal edict of September 20, 1782, prescribed the

sequestration of the phthisical, the disinfection of the rooms,

chattels, movables, books, etc., with vinegar, eau-de-vie, lemon juice,

sea-water, fumigations, etc., under a penalty of three years at the

galleys, or in the case of nobles, of three years imprisonment and a

fine of 300 ducats. A physician who failed to report a case of

consumption was fined 300 ducats for the first offense, and banishment

for ten years in case of a second. Any one assisting in such evasion of

the law was sent to prison for six months.

“Chateaubriand found that, in 1803, he could not sell his carriages in

Rome, because Mme. Beaumont, who had died of consumption, had ridden in

them three or four times. George Sand, who was with the phthisical

Chopin in Minorca in 1839, was refused a lease of the house for the

second month, and the price of repainting and purifying was demanded.

Later, in Barcelona, they were assessed for the bed on which Chopin had

slept, as the police regulations prescribed it should be burned.

“This was not a mere survival of vulgar prejudice. Jacobi tells us of a

dog which died of consumption from eating the sputa of his phthisical

master. Laennec, the discoverer of auscultation, and the great authority

on pulmonary consumption, records that he himself contracted a

tuberculous nodule, through a wound with a saw, while making a necropsy

in a case of phthisis. Laennec died of tuberculosis later, although he

seemed to have checked this lesion by caustics. Andral joins Laennec in

enjoining the greatest caution and cleanliness in taking care of, or

associating with persons having advanced tuberculosis.

“Cullen, who started with a strong prejudice against the doctrine of

contagion, leaves us the following instance of its occurrence: ‘A young

man predisposed to phthisis married a Dutch girl of a sanguine

temperament and good constitution. Some days after the marriage the

woman lost her fresh color and was attacked by a bad cough; a month

later she commenced spitting blood. The physician advised her not to

sleep in the same bed with her husband, but she refused to follow his

advice, and six months later she died of phthisis. The servant who took

care of her and the domestic, who avoided, as far as possible, staying

in the sick chamber, both died of consumption.’

“Wickmann, court physician in Hanover, in 1780, pronounces emphatically

for contagion. In Zurich, at that time, one death in every six was from

phthisis. The contagion of phthisis was slow in its operation, and was,

therefore, less evident than that of plague, smallpox, scarlatina and

other affections attended by a skin eruption, but it was no less real

and deadly. It was also less frequently indirect, or carried from victim

to victim by intermediate agents. He cited instances of the transmission

of consumption from husband to wife and vice versa, and claimed that the

marriage of a phthisical person should be legally prevented. As a means

of preventing the disease, he proposed a strict surveillance of

establishments for the sale of old clothes, and the avoidance of leaving

infants with consumptives.

“Valsalvi and Sarconi refused to make necropsies of persons who had died

of phthisis.

“Dr. Ruhling, of Gottingen, writing in 1774, of the disease in animals,

says: ‘The malady is transmitted to sound animals by direct contact of

animals standing side by side in the stall, and licking each other, and

breathing the expired air direct from the diseased lungs; the

frequenting of the same pastures will also serve to propagate it.’ In

Krunitz’s encyclopedia, published in Berlin, in 1787, is the following:

‘The heifers show an ardent desire for the male, and remarkably enough,

do not become pregnant, but part with the fruit of conception. When

opened these animals show the first stomach, kidneys and surface of the

lungs, covered with pustules like dried mulberries or in suppuration.

The affection is contagious, and communicates itself from one animal to

another by contact.’

“Fromage, in the Dictionaire de Rozier, Article Phthisis, says: ‘Men of

art are very much in accord that this malady is not contagious, but some

stock owners think differently.’

“Huzard, who saw much of tuberculosis in the Parisian dairies in the

concluding decade of the last century, said that most of the

veterinarians looked upon the disease as contagious, and that some of

the physicians believed the same of the phthisis of man.

“Dewar, speaking of his experience in Scotland in 1839, and succeeding

years, in a particular herd, says: ‘The proprietor agreed to remove

partition walls, and to make openings opposite one another in the

outside walls, so that there might be a current of fresh air passing

through. These alterations combined with cod liver oil, tonics and

stimulants, may have prolonged life but yet no cure was effected, and

that herd died out. I resorted to every precaution when new cattle were

purchased to prevent infection; as I had an idea, even at that time,

that the disease might be communicated from one to another when in

immediate contact. The precautions adopted when fresh cattle were

purchased had the desired effect, for in a few years afterward, they

were as good a lot of cattle as any in the district. That herd left an

impression on my mind that never can be effaced, and made me always

dread the evil consequences of tuberculosis. Having practiced in the

same locality, which is an extensive breeding and rearing district, I

have seen several herds decimated. Though I have sometimes foretold the

owner what he might expect, yet he did not believe me until so many were

infected that the byres were infested with the fearful malady, and your

remarks in regard to nose contamination are so true that I do not think

it possible any can escape that are so exposed. I have also seen, as

Grad has, the same stall infecting beast after beast until a thorough

cleaning and disinfecting, with plenty of fresh air had removed all

infection.’

“Spinola, writing in 1858, of bovine tuberculosis, gives contagion as a

possible cause, and Lafosse, in 1867, says: ‘Physicians begin in

imitation of Morgagni to believe in the contagion of phthisis. The facts

published by Villemin appear to support this opinion, which has been

held by our colleague, Dupont, of Bordeaux, for several years.’

“Cruzel in his work of date, 1868, is much more positive; he says: ‘This

fœtid expired air, inhaled immediately by another cow upon a sound lung,

gives the latter tuberculous infection. It is a matter of every day

experience to the veterinarian. Two oxen or cows are kept in the same

stable, take their food from a common rack or manger, lie in the same

stall, and respire nose to nose. The one is, to all appearances,

perfectly sound, the other is in as good a condition, and is vigorous,

but it coughs from time to time, and its breath is foul. Soon we notice

that the animal that does not cough, eats with less appetite, he loses

flesh and soon he is unequivocally affected with the same malady as the

first.’ The foregoing quotations show clearly that in spite of the

misleading teachings of Broussais and others, the doctrine of contagion

in tuberculosis could not be overcome, and that up to the time of the

remarkable experiments of Villemin, in 1865, it maintained its hold upon

the minds of extensive and careful observers. In animals, especially,

the evidence was so frequent and clear, animal following animal in the

same stall, and eating from the same infected manger, only to be

infected in turn, and two animals stalled together, and licking the same

manger with their prehensile tongues, transmitting the infection with

certainty the one to the other, were facts that could not possibly be

ignored. Other cattle in the same building might escape for a length of

time, but the eating in common from the same fatal manger, by a

tuberculous and a healthy animal, quickly sealed the fate of the latter.

“Physicians, too, who were compelled to investigate the causes of the

extraordinary fatality from tuberculosis in the armies and navies, could

not shut their eyes to the fact notwithstanding that they came to the

task strongly prejudiced through education against the acceptance of

contagion. Thus, Dr. Bryson, in his report to the Epidemiological

Society, in 1860, on consumption in the several ships of the English

navy on the Mediterranean station, says distinctly that the disease

appeared to be propagated by contagion. Dr. Parkes, quoting this in his

Practical Hygiene, says: ‘It may be inferred that pus cells were largely

thrown off during coughing, and floating through the air, were received

into the lungs of other persons. The production of phthisis in animals

confirms this view. The case of monkeys in the zoological gardens,

narrated by Dr. Arnot, is a striking instance. Cows in close stables

frequently die of phthisis. But not only phthisis may reasonably be

considered to have one of its modes of origin in the breathing of an

atmosphere contaminated by respiration, but other lung diseases,

bronchitis and pneumonia, appear also to be more common under such

circumstances.’

Villemin in 1865, published his investigations in which he had produced

tuberculosis in a great number of animals, by inserting particles of

fresh tubercle or injecting the tuberculous sputa of man into the

subcutaneous connective tissues, the peritoneum and the trachea. There

resulted in nearly every case a chronic disease, the marked phenomena of

which were caseated centers devolving from firm inflammatory nodules in

the seat of inoculation, in the adjacent lymphatic glands, in the lungs,

serous membrane, liver, spleen and kidneys. The centers of such nodules

were at first transparent and grayish, but soon the center underwent

necrobiosis, forming a soft cheesy mass the size of a pin’s head, and

gradually enlarging to that of a pea, a bean, a hazel nut or larger.

After a period of about 14 days the lymphatic gland nearest the seat of

injection could be felt as a firm pea-like nodule, and in two weeks more

a second gland on the line of the lymph circulation, had become enlarged

and nodular, while the first, now the size of a large bean, had probably

undergone distinct softening. This became adherent to the skin, burst

and discharged continuously or at intervals with little or no tendency

to heal. If killed at this date, the animal showed only the open sore

and a chain of nodular pea-like caseated lymphatic glands leading up

from it. The lungs might be apparently sound, but the spleen and liver

usually showed miliary elevations on the surface, with clear grayish

centers, as viewed under a magnifying glass, opaque patches were found

on the omentum, and the lymphatic glands of the mesentery, of the portal

fissures of the liver and of the Hilus of the spleen were distinctly

enlarged and resistant. If not killed, the subject usually died 100 to

120 days after inoculation, and then the lungs were found studded with

tubercles miliary or larger and more or less caseated; the bronchial

mediastinal, subdorsal, pectoral, prepectoral, phrenic, mesenteric,

hepatic, and splenic lymphatic glands were more or less enlarged and

caseated, while the liver and spleen were enlarged and studded with

multiple tubercles. Guinea pigs give the most extensive and intensive

lesions, rabbits much less so, but in both emaciation and wasting are

very marked. In short the lesions are essentially and unmistakably those

of generalized tuberculosis.

“At first, however, incredulity prevailed and experiments on a large

scale were inaugurated all over Europe and America to put the question

to crucial test. Martin, Conheim, Burdon-Sanderson, Simon, Wilson, Fox,

Lebert and Wyss, Fraënkel, Waldenbourg, and others inoculated with all

sorts of non-tuberculous organic materials (bronchial mucus, foul pus,

cancer juice, diseased liver, simple cotton setons, etc.) and from these

in Guinea pigs there resulted local caseated foci, and implication of

the adjacent lymphatic glands. It was found that the liquids from low

types of pneumonia produced these apparently tubercular deposits, while

that from acute sthenic pneumonia did not; that the cotton thread seton

failed to produce the disease if it were first steeped in carbolic acid,

and that the lesion caused by breaking a bone without injury to the skin

failed to produce the characteristic lesions even in the very

susceptible Guinea pig. It became evident, therefore, that the morbid

results in these cases, were due to accidental inoculations with the

poison of the tubercle, which is widely distributed, or with some pyæmic

or other germs.

“Gradually the truth triumphed, and those who had at first been loudest

in their opposition were led by their own experiments to become the

firmest supporters of the new truth.

“As early as 1874, Gerlach had experimented largely in feeding the milk

of tuberculous cows, and had infected calves, pigs, sheep and rabbits in

this way. Chauveau in (1874), Klebs (1873), Semmer (1880) and Parrot

(1870) fed calves, cats, Guinea pigs, pigs, sheep and a variety of other

species of animals with tuberculous flesh or lungs, or saliva, producing

tuberculosis in a large proportion of cases. In this manner they escaped

the charge of the operation of a wound and of ærial bacteria, and yet

succeeded in producing infection. The lesions in this case began in the

intestinal mucous membranes and mesenteric glands.

“Another essay in the same direction was made by Tappeiner (1878), who

infected rabbits, Guinea pigs and dogs, by enclosing them in boxes and

compelling them to breathe tuberculous liquids intimately mixed with the

air atomization. In these cases lesions began in the lungs and bronchial

and mediastinal glands.[1]”

Footnote 1:

(From Report to the N. Y. Legislature, 1895. James Law.)

_Bacteriology._ The _bacillus tuberculosis_, the essential cause of

tubercle, was demonstrated by Koch in 1882. It was at first supposed to

be peculiar in its indisposition and tardiness to take a stain, and in

its retention of the stain once imparted, even when it is treated with

acids. Later observations have shown that these characteristics are

common to certain other bacilli, notably to those of leprosy, smegma,

and to specimens found in timothy hay and other grasses, cow dung, milk

and butter. These furnish sources of fallacy in the milk and butter

especially, but when the specimens examined are taken from the interior

of a tubercle, lymph gland or serous cavity the danger of error may be

practically ignored. What is quite as important is the fact that the

tubercle bacillus is subject to evolutionary changes in adapting itself

to a habitat in different genera of animals, and to a lesser extent in

different parts of the same animal, by which its pathogenesis is

modified, but these variations do not materially affect the staining

qualities. Still more striking variations have been found in old

cultures, ovoid forms (Metchinkoff), club-shaped microbes and filaments

(Metchinkoff, Klein, etc.), branching filaments (Fischl, Coppen Jones),

divergent club-shaped groups, like actinomyces (Babes and Levaditi). The

last named, seen in inoculated rabbits, have been held to establish a

relationship between the microbes of tuberculosis and actinomycosis, as

the club-shaped cells do not take the usual Ziehl-Neelsen stain for

tubercle bacilli, but the Birsch-Hirshfeld’s actinomyces stain. Apart

from the rabbit such variations are not likely to prove sources of

fallacy in identification of the microbe.

_Morphology._ As met with in the tubercle of man or ox the bacillus is a

minute rod with rounded ends, 1.5 to 3.5μ long, by 0.2μ in thickness. In

the ox it is shorter and thicker on an average than in man. They are

usually solitary, but two and exceptionally even three or four elements

may be united. In stained specimens unstained portions are frequently

seen (spores?). When cultivated on blood serum there is a tendency to

form elongated rope-like colonies having a waving outline. Other

evolution forms have been already noted.

_Staining._ The resistance to staining is overcome by a heated alkaline

watery solution of methylene blue (Koch), or better by a carbolated

solution of fuchsin (Ziehl-Neelsen). To a 5 per cent. watery solution of

carbolic acid add one tenth of its volume of saturated alcoholic

solution of fuchsin. The suspected sputum or scraping from a section of

a lesion is spread in a thin layer on a cover glass by drawing over it

the straight edge of a second cover glass, dried in the air, and passed

three times through an alcohol flame with the smeared side up. It may

then be floated on the surface of the staining fluid with the specimen

side down, then gently heated for three or four minutes almost to

ebulition, drying being prevented by the addition of more of the

carbol-fuchsin solution as required. It is then washed in water to

remove excess of the staining fluid and treated with a bleaching acid

solution (sulphuric acid 5 per cent. or nitric acid 15 per cent.) When

decolorized it is well rinsed in two or more portions of a 60 or 70 per

cent. alcohol and then in water. Next stain with a 1 or 2 per cent.

aqueous solution of methylene blue for one minute and wash off the

excess with water. The tubercle bacilli will appear of a deep red and

other bacteria blue.

_Gabbett’s_ counter-staining and decolorizing solution is especially

useful in economizing time. After staining, as above directed, in the

carbol-fuchsin solution for one minute, wash in water, then cover with a

solution of 2 grams methylene blue (powder) in 100cc. of 10 per cent.

sulphuric acid, until the film has a faintly bluish tint: then wash

thoroughly in water and examine. Tubercle bacilli come out red, others

blue.

In _examination of tissues_ the microscopic sections are steeped for

twenty-four hours in the carbol-fuchsin solution (or 1 hour at a

temperature of 45° to 50° C.), then decolorized in a 5 per cent.

sulphuric acid for a few seconds, then in a 70 per cent. alcohol: they

are then counter-stained in an aqueous solution of methylene blue,

washed in water dehydrated with absolute alcohol, cleared up in xyol or

oil of cedar, and mounted in Canada balsam.

_Biology._ The _bacillus tuberculosis_ is notorious for its variant

forms, assumed in adapting itself to given environments, and which it

retains with considerable tenacity for a time, even when placed in a new

and different medium. It is largely held to be an obligatory parasite,

and incapable of survival as a saprophyte, yet Straus, Nocard and

others, have shown that the form obtained from the tuberculosis of birds

can easily be made to live in suitable dead mixtures of organic matter.

It is also notorious that the bacillus taken direct from the tubercle of

the mammal, and which, as a rule, fails to grow at once in glycerined

bouillon, yet, after a first successful culture in the new medium, often

adapts itself completely, and thereafter it can in many cases be

transferred from bouillon to bouillon, with as great certainty as it

could formerly be inoculated from ox to ox. The difference is one of

habit and adaptability, rather than any primary and permanent

distinction of species. There is every reason to believe that the

microbe has lived, and under given conditions can still be made to live

as a saprophyte, with a greatly reduced adaptability to parasitic life

in the animal, just as we see to-day that it is only with great

difficulty transferred from certain genera of animals to certain other

genera (from bird to ox and vice versa). Trudeau tells us of a culture

of a bacillus tuberculosis from man, inoculated on the rabbit and then

cultivated _in vitro_ in successive generations for six years, that was

in this way robbed of its pathogenesis for Guinea pigs, which, after

inoculation, lived for many months, some two and a half years, and some

even recovered. The average duration of life in the Guinea pig, after

tuberculosis inoculation from man, rabbit, Guinea pig or recent culture

is but seventeen days. The bacillus of human sputum often produces only

localized tuberculosis in the ox. Even in the same species and

individual the pathogenesis often varies materially. Nothing is more

familiar than the slow progress of tuberculosis in the bones and lymph

glands of man, on the one hand, and its frequently rapid progress in the

lungs, liver and brain, on the other. As inoculated on the lower animals

bacilli from the lungs of man are usually more virulent than those from

the lymph glands (Creighton, Arloing, F. Craven Moore, Courmont and

Denis). Among seven specimens of human sputum, the bacilli in six cases

showed a fair average vitality, whereas those of the seventh failed to

grow on blood serum of the dog (Theobald Smith). In both man and cow a

large proportion of cases of tuberculosis remain localized, the disease

lasting for years with little or no appreciable advancement, and not a

few subjects appear to make a permanent recovery.

On every hand this evolutionary tendency of the bacillus tuberculosis

places itself in evidence, demanding a recognition of the fact, that

more or less transient or lasting variations in accordance with previous

or existing environment, control to a large extent the transmissibility

of the disease among different genera and even among individuals of the

same genera and species, and also the fatal progress, or the mild and

evanescent issue of the infection.

Even the most widely divergent of these evolutionary forms can often be

made to approach each other and apparently merge into one type.

Profiting by the example of Metchnikoff, Nocard enclosed in collodion

capsules the bacilli of the human sputum and inserted the capsules into

the peritoneal cavity of chickens which had proved refractory to their

direct inoculation. This excluded the direct action of the leucocytes

from the encapsuled bacilli, but allowed the endosmosis of the serum of

the fowl for their nourishment. After a sojourn of four months or more

they were transferred to other capsules and again enclosed in the

peritoneum and after a second and third transference of this kind it was

found that the bacillus had become actively pathogenic for the chicken,

having acquired the infecting potencies of the bacillus of avian

tuberculosis.

In keeping with the above is the fact that both rabbit and horse are

easily infected by the bacillus obtained from birds, and that after a

certain number of transmissions through the rabbit the issue of the

bacilli of bird and mammal appear to become identical. No less

instructive are the cases of the infection of carp by human sputa and

the conveyance of tuberculosis to rabbits and Guinea pigs by inoculation

with the nodules of the infected carp.

The _vitality_ of bacillus tuberculosis is strong but variable. In

sterilized water at 46° to 64° F. the human bacillus survived for fifty

to seventy days (Chantemesse and Vidal), the bovine indefinitely

(Galtier) and the avian bacillus at a higher temperature one hundred and

seventeen days (Straus and DeBarry). In dried expectoration the bacillus

of man still infects after nine or ten months (Koch, Schill, Fischer, De

Thoma). In infected cow’s lung, dried and pulverized, it infected Guinea

pigs at 102 days (Cadeac and Malet). In putrid matter it infected after

43 days (Schill, Fischer), 167 days (Cadeac and Malet), several years in

a grave (Schottelius).

It is not destroyed by gastric juice (Fischer, Falk). The bacillus from

tubercle of birds has a much greater vitality than that of mammals.

Marfucci successfully seeded new media from a culture of two years old,

and cultures in artificial media can be started more successfully.

Full _sunlight_ renders sputum on a solid nonabsorbent surface

noninfecting in several hours, varying according to the thickness of the

layer (Koch, Straus). When sputum is mixed in soil it may survive until

the 137th day (Feltz). On woolen cloth it may live five hours (Migneco).

_Diffuse daylight_, with shading from the sun, killed in seven days

(Koch), to eighteen days (Lucibelli).

_X-Rays_ do not arrest the growth of cultures (Blaikie, Pott, Ausset).

A _dry temperature_ of 212° F. for an hour left some of the bacilli

still infecting to Guinea pigs (Lartigan).

A _moist heat_ of 140° F. for one hour sterilizes (De Man, Th. Smith,

etc.). The scum formed on the milk may still prove infecting (Th.

Smith). Half an hour of a moist temperature of 212° F. is sterilizing.

Yet in the case of steaks, roasts and boiled meats the size of the piece

often prevents the reaching of this temperature throughout, and it

becomes unsafe to use any meat in which the redness of the juice shows,

that the albumen has not all been fully coagulated (162° F.).

A _freezing temperature_, −16° to −26° F., does not devitalize the

bacilli, even when alternated with thawing at intervals for several

weeks (Galtier, Cadeac and Malet).

_Heavy salting_ of meats has been thought to kill the bacillus in a

month. After 15 days in salt the microbe failed to kill rabbits, but

still killed the Guinea pig, whereas after 30 days it killed neither

(Galtier). The fact that salted meats are always unequally impregnated

in different parts, renders this extremely unreliable and more of a

snare than a guide.

The action of chemical disinfectants varies not only with the agent but

also with the medium in which the bacillus is found. In simple liquid

media (bouillon) the following results were obtained:

_Parts per 1000._ _Killed in._

Carbolic Acid 50:1000 30″ (Yersin)

„ „ 10:1000 1′ „

Alcohol (absolute) 1000:1000 5′ „

Ether 1000:1000 10′ „

Iodoform ether 10:1000 5′ „

Mercuric chloride 1:1000 10′ „

Salicylic acid 2.5:1000 6 hrs. „

Anilin water Saturated ———————— ——————— ————————

Thymol 3:1000 3 hrs. (Yersin)

Formalin vapor 60:1000 40 hrs. (Murray)

Sulphurous Acid (Sulphur 1 oz.

to cubic metre) ————————— 14 hrs. (Vallin).

The following agents proved ineffective: Saturated aqueous solution of

creosote, or of B-naphthol, of naphthalin, of potassium iodide, of

potassium bromide:—bromine water, iodine water (1:500), iodoform

solution or vapor, vapor of oil of turpentine.