the danger of
scattering the virus by careless handling in wagons that are not tight. As
a rule, the persons in charge of such transfer have no training for this
important work, so that deep burial is to be preferred. Burning large
carcasses is not always feasible; it is, however, the most certain means of
destroying infectious material of any kind, and should be resorted to
whenever practicable and economical. All carcasses, whether buried,
rendered, or burned, should be disposed of unopened. When stables have
become infected they should be thoroughly cleaned out, and the solution of
chlorid of lime freely applied on floors and woodwork. The feed should be
carefully protected from contamination with the manure or other discharges
from the sick.
(2) Preventive inoculation.--One of the most important discoveries in
connection with the disease was made by Louis Pasteur in 1881, and
consisted in the new principle of producing immunity by the inoculation of
weakened cultures of the bacillus causing the disease. This method has been
quite extensively adopted in France, and to some extent in other European
countries, and in the United States. The fluid used for inoculation
consists of bouillon in which modified anthrax bacilli have multiplied and
are present in large numbers. The bacilli have been modified by heat so
that to a certain degree they have lost their original virulence. Two
vaccines are prepared. The first or weaker, for the first inoculation, is
obtained by subjecting the bacilli to the attenuating effects of heat for a
longer period of time than in the case of the second, or stronger vaccine,
for a second inoculation some 12 days later.
There are several difficulties inherent in the practical application of
Pasteur's vaccine. Among them may be mentioned the variable degree of
attenuation of different tubes of the vaccine and the varying
susceptibility of the animals to be inoculated. The use of this vaccine is
increasing, nevertheless, and has reduced the mortality in the affected
districts from an average of 10 per cent in the case of sheep, to less than
1 per cent, and from 5 per cent with cattle, to less than one-half of 1 per
cent.
It is very important to call attention to the possibility of distributing
anthrax by this method of protective inoculation, as the bacilli themselves
are present in the culture liquid. It is true that they have been modified
and weakened by the process adopted by Pasteur, but
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