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Abel (a) found living bacilli of plague in water after twenty days. 
He added an oese to 50 c. c. of sterile distilled and tap water. 
The German Plague Commission (b) found that the organism was 
no longer virulent after five days in tap and ten days in distilled water. 
Yokote (c) worked on the problem of how long the plague bacillus 
can remain alive in the dead body. He used mice for his experiments 
because they are very susceptible. The mice were inoculated and the 
presence of the bacilli demonstrated in the heart’s blood of the dead 
animals, which were then placed in a wooden casket. Each casket was 
covered with a lid and then buried in a metal box filled with garden 
earth. From time to time water was poured on the earth so that it 
always had a certain moisture. The temperature of the room was taken 
daily. After a certain time the bodies were disinterred, the amount of 
moisture present in the earth surrounding the casket determined quan- 
titatively, also examined bacteriologically and by animal experiments 
for pest bacilli. Mice were used for this purpose, and glycerin agar 
for culture medium. 
^ On disinterring the body the amount of decomposition was noted, and 
by means of cover-glass prepartions he determined the characters and 
numbers of micro-organisms present in the various organs. Plate cul- 
tures were made from the internal organs, on agar-agar, and some of the 
heart’s blood, liver, or in case of advanced decomposition, some of the 
remains were inoculated into mice subcutaneously. 
I As a result of these experiments, he concludes that the pest bacillus 
loses its life and its power of infection in a relatively short time. It 
remains alive, at most, twenty to thirty days. This depends on the 
temperature. The higher the temperature, the stronger the decomposi- 
tion, the shorter the life of the bacillus. In summer many saprophytes 
grow in the body and cause products which kill the pest bacillus. In 
cold winter this growth of saprophytes is less, and the pest bacillus 
could therefore live and maintain its virulence a longer time. 
He states that his experiments are not sufficient to determine posi- 
tively the length of time the pest bacillus may live in a buried body, 
but he gives it as his belief that the organism can not live longer in the 
cadaver than spore-bearing organisms because it does not have spores. 
It is also of interest to notice that the pest bacillus did not escape from 
the wooden casket into the surrounding earth. It seems, therefore, 
that there is no danger in the burial of pest cadavers of infecting the 
I surrounding earth as long as the coffin is tight. 
a Loc cit. ' h Loc cit. 
c Uber die Lebensdauer der Pestbacillen in der beerdigten Tierleiche. Dr. Z. 
Yokote. Centralblatt fur Bakteriologie und Parasitenkunde, etc., Vol. XXIII, 1898, 
No. 24, page 1030. 
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