BACILL'US OF SYMPTOMATIC ANTHRAX 



467 



tible. Dogs, cats, rabbits, and birds are immune. Man also appears 

 to be absolutely immune. Spontaneous infection occurs by the en- 

 trance of infected soil into abrasions or wounds, usually of the lower 

 extremities. Infection depends to some extent upon the relative de- 

 gree of virulence of the bacillus a variable factor in this species. 

 Twelve to twenty-four hours after inoculation there appears at the 

 point of entrance a soft, puffy swelling, which on 

 palpation is found to emit an emphysematous crack- 

 ling. The emphysema spreads rapidly, often reaching 

 the abdomen and chest within a day. The course 

 of the disease is extremely acute, the fever high, 

 the general prostration extreme. Death may result 

 within three or four days after inoculation. 



At autopsy the swollen area is found to be 

 infiltrated with a thick exudate, blood-tinged and 

 foamy. Subcutaneous tissue and muscles are 

 edematous and crackle with gas. The internal 

 organs show parenchymatous degeneration and 

 hemorrhagic areas. The bacilli, immediately after 

 death, are found but sparsely distributed in the 

 blood and internal organs, but are demonstrable in 

 enormous numbers in the edema surrounding the 

 central focus. 



If carcasses are allowed to lie unburied for some 

 time, the bacilli will attain a general distribution, 

 and the entire body will be found bloated with* gas, 

 the organs filled with bubbles. Practically identical 

 conditions are found after experimental inocula- 

 tion. 



Toxins. According to the investigations of Le- 

 clainche and Vallee, 1 the bacillus of symptomatic 

 anthrax produces a soluble toxin. It is not formed 

 to any extent in ordinary broth, but is formed in 

 considerable quantities in broth containing blood or albuminous ani- 

 mal fluids. 



The best medium for obtaining toxin, according to the same authors, 

 is the bouillon of Martin, 2 made up of equal parts of veal infusion and a 



FIG. 100. BA- 

 CILLUS OF SYMP- 

 TOMATIC ANTHRAX. 

 Culture in glucose 

 agar. 



1 Leclainche et Vallee, Ann. de 1'inst. Pasteur, 1900. 



2 Martin, Ann. de 1'inst. Pasteur, 1898. 



