NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
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upon gelatine, whereas, after exposure for an hour to a 1 in 50,000 solu-
tion, the growth was as vigorous as in the control experiment. Quinine
impedes the development of anthrax bacilli at a dilution of a 1,200 per
million, and entirely prevents it at 1,600 per million.
What becomes of the microbe in the cadavers, cadaveric debris
water and soil.—In the bodies of animals dead of anthrax, putrefaction,
as we have already seen, is promptly established, because the vibriones of
septicæmia which always exist in the digestive and the air passages, where
they are introduced by food, water and air, not being impeded by the action
of the cellular elements which have lost their vitality too greatly, find
themselves in a particularly suitable medium, more especially as the
bacilli of anthrax have left little oxygen; they consequently rapidly
develop and invade all the organs. For this reason, when we wish to
examine the blood of an animal to decide whether or not he has succumb-
ed to anthrax, it is necessary to do so as soon after death as possible, and
it is also imperative to take antiseptically, as soon after death as possible,
products which we intend to examine later on. A few hours after death
the action of the septic vibriones may mask the result, and the inocu-
lation of a charbonous material which has become septic lead to septicæmia.
In the blood and organs of animals dead of charbon, the bacilli re-
quire air for their existence which is not forthcoming, they find them-
selves in the presence of the carbonic acid given off by the septic vib-
rione, and the temperature not being a suitable one, as a rule, they do
not form spores nor filaments, although they may ocrasionally elongate
in the blood, and they do not consequently develop; they perish more
or less quickly.
So, then, if they do not form spores in the blood of the sick animal,
as we know they do not, it is the same in the cadaver, so long as the
blood does not become exposed to the air; for if after two or three
days we remove blood from a cadaver and heat it to 60º or 70º, a
temperature sufficient to destroy the rods but not the spores, it does not
fertilize a culture sown with it. In the same manner charbonous cada-
vers lose their virulence if anything more surely and more quickly accord-
ing as putrefaction comes on quickly or slowly. Everything which
facilitates putrefaction hastens the destruction of the microbe. The
length of time during which the bacillus anthracis remains alive after
the animal's death varies with the temperature; cold—a temperature
below 10º C.—facilitates its preservation. We may find it living after
four or five days in a moderate climate, and seven or eight days in a cold
climate. Canal has found it living in charbonous meat after eight
days; Nocard has likewise found it living and active after 17 days in
the carcase of a guinea-pig. When the surrounding temperature attains
49
18 º , 20º, 25º C., the cadavers preserve their virulence for a much shorter
period. In addition to this, all things being equal, the virus preserves
its life for a much longer period when the carcase containing it has been
opened and cleaned. It preserves itself equally in cadaveric débris in
the charbonous products, in the dejecta and excretions of the sick, in
the urine and fæces; putrefaction causes them to lose their virulence.
But, thanks to the presence of air, spores may form in these various
products, and in that case, of course, the virulence persists for a longer
time. The virulence of charbonous meat may or may not be destroyed
by salting (Peuch); after a thorough salting it may be, but after an
incomplete one it may preserve its vitality.
If the bacilli do not form spores in the cadavers, as we know they do
not, when they do not gain access to the air, still those which are rejected
from the mouth, nose, and anus in the blood which usually flows from
these natural orifices, also those in the urine and excrements, gaining, as
they do, exposure to the air and oxygen, go on to spore formation. The
bacilli are often exposed to the air in this manner, or by skinning the
carcases before burying them, or by allowing the blood and excretions to
remain on the latter, etc., and spore formation takes place. The spores,
once formed, preserve their vitality and their virulence for years; they
will remain latent, but capable of development when introduced into
suitable surroundings,—such as, for instance, the body of an animal sus-
ceptible to the malady; and hence it is that we are constantly observing
the appearance of charbon in animals pastured on land where animals
have died of the disease, or where they have been buried, or on land
which has been manured with manure from stables, etc., where anthrax
has been prevalent. Besides this, by cutting up a portion of a charbon-
ous organ, such as the spleen, into fairly thick pieces, and drying it at a
temperature of 25º to 35º C., the rods may bear spores which remain pre-
served for along time, and are, if anything, the more resistant the more
they become dried; whilst if we cut up the organ into finer portions,
or if we rapidly dry it, the rods perish. From this we may gather what
is likely to occur in the excrement or other products strewn on the
ground, roads, etc. Virulence persists when spores have had time to be
formed; it persists in the soil of ditches or holes, manure, urine, water,
and on pastures.
When we mix charbonous blood with the earth experimentally the
microbe lives and multiplies if the temperature is propitious, and more
especially so when the ground is watered with urine, etc. Spores are
formed and may be found several months afterwards in the soil after
numerous changes of atmosphere and temperature. These spores being
sown on a new soil, and this again in another (successive cultivations)
the last one may produce charbon.
E
50
Pasteur and Schrakramp have observed that the bacillus runs through
the whole course of its development in the soil. It is very probable
that spores sometimes cultivate in stagnant water rich in organic
matter. We have observed the presence of charbonous germs in water
where they have been carried by the rain.
It has been perfectly clearly demonstrated, by experiment and by
observation that charbonous germs are preserved in the soil. "By
washing suspected earth and allowing the water to settle," says Pasteur,
"then submitting the deposit so obtained to a temperature of 90º C. for
some minutes, we destroy all the germs excepting the spores of anthrax
or septicæmia, if there are any; by inoculating animals with this deposit
we get in some septicæmia, and in others charbon. In this manner the
presence of charbonous germs has been detected in earth from graves
three to twelve years after burial of animals suffering from charbon;
animals have been seen to contract charbon after having eaten herbs, etc.,
grown on graves two years after burial; forage deposited on soil con-
taining spores of charbon has been observed to commuicate the malady.
Spore formation occurs more especially in the superior layers of the soil,
but it may occur also in the deeper layers when the soil is permeable
and the temperature favourable; Soyka has noticed that it occurs more
rapidly in a humid soil than even a culture medium. it does not occur
in water deprived of organic substances (Rivolta), but the spores are
preserved in the water. In the same manner, according to the researches
of Kochstetter, whilst the bacillus is preserved three days in distilled
water, in ordinary water the spores remain for more than 154 days;
according to the researches of MM. Straus and Dubarry, the bacillus
may exist for two months in water, and the spores more than 130 days.
To sum up, these charbonous germs preserve their vitality for years in
the soil which covers charbonous animals' graves, and in the soil surround-
ing them; this soil may communicate charbon twelve years after the
burial of the carcass, and perhaps even a longer time. We may discover
germs in such graves, and may by intravenous injection of rabbits, guinea-
pigs, or sheep, which are not easily susceptible to septicæmia, with the
residue of the deposit from water with which they have been washed,
induce charbon and thus verify the suspected material.
Although the cadavers have been buried at a good depth, charbon
germs, despite the filtering action of the soil, remount to the top of the
graves, where we find them, as has already been seen; Pasteur, Feltz,
and Boilinger contend that they are brought to the surface by means of
earth-worms, but this view is denied by Koch, who claims to have proved
to the contrary by experimentally burying earth-worms in earth con-
taining the spores, and on careful examination of the casts of these
worms, finding no trace of charbonous germs of any kind. Pasteur,
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Feltz, and Bollinger, however, state that worms proceeding from char-
bonous graves deposit in their casts, and especially those found in spring
and autumn, such a number of these germs that it is sufficient to inocu-
late the deposit from the water with which these have been washed to
produce the disease. Pasteur has been able, by employing certain an-
tiseptics which have little or no effect on the virus of charbon, but which
destroys a great number of other germs contained in earth, to cultivate
and obtain a pure culture from the casts of worms.
Pasteur, and later Feltz, by mixing the bacillus in earth and causing
worms to live in it, have observed after some days that the casts extract-
ed from these worms contained the germ of the disease, for they gave it
on inoculation, and it was possible to cultivate it from them. It has
been in addition to this remarked that on soils in which worms do not
live, such as schistous, granitic and chalky, charbon is unknown, whilst
where the soil is clayey, loamy or alluvial, it is common. On the other
hand, it is very natural to suppose that worms are not the only means
by which charbon germs are brought to the surface; all creatures which
live in the subsoil may bring up the germs.
The germs so brought to the surface of the soil spread about attach-
ing themselves to plants; they may be taken up with dust, by the feet
of animals, penetrate into the respiratory passages, attach themselves to
the skin, hair, or wool; they may be carried by rain and deposited at
some distance; they may be carried into streams, ponds, pools, tanks,
swamps, deposited on their banks, and thus have more opportunities of
penetrating into the organism.
These facts explain the following, which have been frequently
observed: the frequent and successive appearance of charbon in animals
which are pastured on tainted pastures; the cessation of danger in certain
tainted pastures after a certain time; the infection of certain pastures,
which not having previously been dangerous, suddenly become so; the
appearance of charbon on soils where charbonous animals have never
been buried; the appearance of charbon in inundated pastures, etc., etc.
Besides this, other circumstances than the burial of charbonous
carcasses may facilitate the dissemination of germs. The bacilli may, as
has already been explained, form spores in the blood which has escaped
from the sick animal, or from the cadavers, in the dejecta, manure, urine,
and various other matter proceeding from charbonous cadavers, and it
is easy to conceive that there are numerous circumstances which favour
the dissemination of germs, more particularly when we consider that the
germs may multiply and form spores when they arrive on vegetable
detritus, marshy ground, etc. So it has been observed that animals
contract charbon when pastured on marshy ground or land subject to
E 2
52
inundation; animals placed in folds or stables, the floors of which have
been taken from anthrax graves; animals pastured on lands manured
with litter from charbonous sources, and those marching on roads over
which charbonous animals have been travelling. Nocard and Jouanne
have seen the importation of manure, especially artificial manure in the
form of dried blood, lead to an outbreak of charbon. In the same manner
charbon may be introduced into a locality where it did not previously
exist, by the utilization of manure coming from a country where charbon
exists, by the use of manure from horse slaughterers' yards when certain
parts, such as the matter from the digestive canal, have not been steril-
ized, by the excrements of animals which have swallowed the germs
without having become inoculated, etc. Slugs, for example, may swallow
the germs of anthrax and pass them out intact, and other animals may
doubtless do the same. Emigration of animals usually checks or stops
an outbreak when the animals are conducted to non-dangerous pastures,
but when emigration is adopted a danger of corrupting the new pasture
is inevitable; the danger is considerably lessened by submitting the
cadavers and the dejecta of animals, which fall sick after the emigration
has been carried out, to disinfection or destroying them. When the
germs exist at the surface of the soil, rain splashes them up on to the
herbage; dust also carries them on to plants, and it is easy, therefore, to
conceive that herbage and forage may be infected on tainted ground and
thus rendered exceedingly dangerous; we have also seen lastly that water
may contain and spread the contagion, giving rise to charbon in animals
which drink it.
Contagion how produced.—Knowing what has preceded this, it is
perfectly easy to understand how charbon appears and is propagated.
The origin of the affection is always the introduction of the bacillus or its
spore into the organism, and it is consequently of importance to deter-
mine the principal circumstances under which it propagates itself. The
contagious nature of charbon, its propagation by contact, is clearly shown,
as we have seen previously, by numerous observations and experiments
with sang de rate of the sheep, charbonous fever of the horse, splenic
apoplexy of the large ruminants, and malignant pustule in man, which
are of the same nature and may be transmitted by inoculation.
Contagion may occur directly from the sick animal to a healthy one;
this method of contagion is more frequently observed than is indirect
or mediate contagion.
Direct or immediate contagion.—Direct transmission sometimes
occurs from the mare to the fœtus, or from a sick animal or cadaver to
the man who is attending to or working with it.
Intra-uterine transmission.—Brauell, then Davaine and others as
well, have observed that charbon is not transmitted from the mother to
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the foetus, and that the blood of the latter is not virulent, nor does it
contain rods, when borne by a charbonous mother. They consequently
were led to the belief that perfect filtration occured in the placenta, the
rods being arrested by the flexuous capillaries there. However, it has
been for some years established that this rule is not an absolute one, but
is subject to some exceptions. Although generally we do not observe
the presence of rods nor the existence of virulence in the blood of the
fœtus, although sowings made with the fluid often remain sterile, there
are numerous cases, varying in frequency with the species on which the
observations are made, in which, by a bacteriological examination, by
inoculation, and more especially by culture, we may observe the presence
of the microbe in the organs or the blood of the young creature. Tous-
saint, in verifying whether the blood of the fœtus of a female dead of
anthrax conferred immunity, caused the death of a sheep by the inocula-
tion. There had then in this case been intra-uterine transmission, but as
the autopsy of the dead sheep had been made somewhat late, Toussaint
considered that the germs had passed through the placenta after death.
Messrs. Strauss and Chamberland, in 1882, observed that in acute
charbon in the female guinea-pig, the placenta often allows the microbe
to pass through it, and that the blood of the fœtus becomes in this
manner virulent. Females inoculated at various periods of gestation and
dying of charbon, the blood of the fœtus was examined microscopically,
inoculated into animals, and sown in broth. The microscopical examin-
ation did not as a rule reveal the presence of the bacillus on account of
the few numbers in which it was present in the blood. Cultures were
fecundated sometimes with the blood of various fœtuses; sometimes
with one, two, or more; at other times it occurred that of several flasks
sown with blood from one fœtus, some cultivated, whilst others remained
sterile. On inoculation it was found that a negative result followed
the inoculation of the cultures which remained sterile; sometimes also
a similar result was obtained with blood which had cultivated in broth.
The result of these experiments shows that culture is the most certain
method of revealing the presence of charbonous microbes in the blood or
tissues of the fœtus, and also in media containing them in small numbers,
and that we should not hesitate to make cultures with a large amount of
seed in such cases.
During the same year, 1882, Perroncito showed that the passage of
the microbe of anthrax from the mother to the fœtus might often occur
in the guinea-pig.
Other experimentors have made similar observations. Koubasoff has
drawn the following conclusions regarding the passage of the bacillss from
the mother to the fœtus. "The bacilli pass from the mother to the fœtas,
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and are, if anything, more numerous in its tissues the longer the mother
survives the inoculation." Malvoz has also observed that the bacillus may
in the guinea-pig pass from the mother to the fœtus, and he has decided
that the passage occurs by means of small vascular ruptures of the
placenta. Birch-Hirchfeld and Rosenblath have both observed the in-
fection of the fœtus through the placenta, one in a pregnant rabbit and
a goat, and the other in the guinea-pig; and they have explained the
passage of the bacilli, as Malvoz has done, by hæmorragic lesions occur-
ring in the placenta. Pangalli has found the bacillus in the blood of
the fœtus of a woman dead of anthrax.
Generally, however, intra-uterine transmission of the bacillus does not
occur. When it does occur, the bacillus appears to accumulate, more
especially in the liver of the young animal.
To sum up, then, the bacillus of anthrax may pass from the mother
to the fœtus, and in this way possibly may be explained certain cases
of immunity of lambs born of mothers which have been affected with
anthrax during gestation, or which have been vaccinated during that
period. In the same way may be explained cases where such immunity
has not been conferred, which is due to the passage not being constant.
So also may be explained the cases of abortion which sometimes follow
vaccination in the sheep and cow, and which are probably due to the
contamination of the fœtus by the vaccinal fluid which destroys it whilst
the more robust mother survives.
Transmission by contact.—When the milk becomes virulent the
young may be infected by sucking; authentic cases of this method of
contagion are, however, not forthcoming. Is this because the digestive
organs of the young animals do not present any abrasions, etc.? Trans-
mission by contact occurs in men working on cadavers or charbonous
débris, who wound themselves during such operations, or who have
already excoriations on the hands, etc. Such transmission has been
frequently observed, and it is the most frequent method by which man
becomes affected with the disease. In order that it may take place, that
the bacilli may be absorbed, it is necessary that the skin be wounded,
excoriated, incised, punctured, etc.; for, when intact, it does not absorb
charbonous microbes.
Indirect or mediate contagion.—Indirect or mediate contagion by
the medium of a solid or liquid vehicle, or by the air; infection, in a word,
by germs which are preserved in the external media, is the most frequent
mode of transmission of charbon. It may occur in three principal ways:
by the ingestion of food or drink containing the microbe; by the in-
halation of dust, etc., mixed with the spores of charbon; and by contact
of a contaminated body with the surface of the absorbents of the skin;
by the stings of flies, and the like.
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Contagion by ingestion.—Contagion is frequently effected by the
ingestion of aliment or water contaminated with the germs of char-
bon. The mucous membrane of the digestive passages, whether it
present abrasions or wounds, or whether it is capable of absorbing the
germs, notwithstanding the fact that it is intact, often serves as the
point of entry of the bacillus into the system. It has been stated that
charbon, which seems to appear spontaneously in regions where it is
enzootic, is often due to the ingestion of germs with the food, which
are ordinarily absorbed by the lesions or excoriations of the mouth and
pharynx, or in other parts of the digestive system. Besides this, the
rôle of the digestive canal in contagion is well established by numerous
observations and experiments.
Barthelmy has seen the horse contract charbon after drinking water
soiled with charbonous débris. Renault had induced charbon in the sheep,
goat, and horse, but not in the pig, dog, nor birds, by causing them to
ingest charbonous materials; the pig, dog, and birds are ordinarily re-
fractory when of adult age. M. Baillet explained the development of
charbon in the mountain pastures of Auvergne by admitting that the
animals contaminated themselves by ingesting herbs or forage or water
contaminated with germs which are rejected from the bodies of the sick,
and from cadavers badly buried, in quantity, and preserve their vitality
in the external media in which they find themselves placed. Davaine
induced fatal charbon in a guinea-pig by causing it to ingest charbonous
flesh.
M. Decroix has observed that the ingestion of virulent material
remained inoffensive. M. G. Colin has seen dogs ingest charbonous
material with impunity, also pigs and birds which have a natural im-
munity; he has also observed rabbits remain unharmed although fed
with the blood of a charbonous animal. M. G. Colin caused the gastric
juice of dogs to act on charbonous material, and found that it did not
produce charbon after inoculation, and hence concluded that charbonous
material which entered the stomach was destroyed. But it has been
observed that charbonous spores are found in active state in the excre-
ment of animals which have swallowed them without contracting charbon;
and, besides this, the spores or germs are often absorbed before
arriving at the stomach, and beyond this if the bacilli under the form
of rods are destroyed by the gastric juice, spores resist and may traverse
the whole digestive tube without having lost their virulence.
The appearance of charbon in animals which have been pastured on
fields where sick animals have previously grazed, and on places manured
with manure from charbonous animals, has already been noticed; it has
been observed in animals which have consumed herbage or forage taken