BACILLUS ANTHRACIS 411 
seven days, or the iiiHained area slowly returns to normal. Less com- 
monly edema is the i)rominent symi)tom, pustule formation being 
absent or not conspicuous. The edematous area spreads rapidly- and 
it may be extensive enough to interfere with the nutrition of the part 
and lead to gangrene. The head, the arms, or the hands are more 
frequently invoh'ed than the lower extremities. 
Intestinal anthrax and pneumonic anthrax or woolsorters' disease 
are usually caused by the ingestion or inhalation of anthrax bacilli 
or their spores. Intestinal anthrax is unconunon; it is supposed to 
be an infection through the gastro-intestinal tract resulting from the 
ingestion of meat or milk of diseased animals. The symptoms are 
essentially those of meat poisoning: chill, vomiting, and nausea, 
diarrhea, and some fever. Woolsorters' disease prevails where hides 
and wool, particularly from South America, Morocco and Russia, are 
handled. The symptoms are: a sudden chill, immediate great pros- 
tration, intense paui, bronchial irritation, and occasionally death 
within twenty-four hours. Cerebral symptoms frequently are promi- 
nent in those cases which are more protracted. There are no distinc- 
tive postmortem changes; the lungs may be edematous and there 
are scattered patches of lobular pneumonia with inflammation of the 
regional bronchi. Shaving brushes made from horse hair that has not 
been sterilized have been shown to contain anthrax spores. A very 
consideral)le number of infections have developed therefrom.^ 
Immunity and Immunization.— The vulnerability of human tissues 
to anthrax infection is varied; the skin appears to be relatively resist- 
ant, but the lungs are very susceptible. The disease resulting from 
infection of the lungs by anthrax bacilli is one of the most rapid and 
fatal known to man. Practically no attempt has been made to 
immunize man to anthrax, but Sobernheim- has prepared a serum 
obtained by injecting animals immunized by Pasteur's method w'ith 
virulent anthrax bacilli, w^hich is said to be of some value as a curative 
agent in malignant pustule. 
Animal Immunization.— Fasteur protected animals against anthrax 
infection by vaccination with attenuated anthrax bacilli. Two vac- 
cines w'ere used; they w^ere prepared in the following manner: Vaccine 
A was obtained by growing anthrax bacilli at 42.5° C. for six weeks. 
The organisms are sporeless after this treatment, but they grow 
luxuriantly. They are avirulent for rabbits and guinea-pigs, but kill 
mice. Vaccine B w^as obtained by growing anthrax bacilli at 42.5° 
C. for two weeks. The organisms kill mice and guinea-pigs, but do 
not kill rabbits. Vaccine A is injected, and after two weeks Vaccine 
B is injected, both subcutaneously. The animals are immune two 
weeks after the last injection to cutaneous infection wdth anthrax 
bacilli, but are somewhat less resistant to infection by way of the 
alimentary tract. The immunity is of about one year's duration, 
1 Smith. Jour. Indus. Hyg., 1921, 2, 42.3. 
2 Ztschr. f. Hyg., 1897, 25, ?.()1. 
