BACILLUS 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 inocular 



tion. 



Toxins. — ^According to the investigations of Le- 



clainche and Vallee,^ 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,^ made up of equal parts of veal infusion and a 



Fig. 100.— Ba- 

 cillus OP Symp- 

 tomatic Anthrax. 

 Culture in glucose 

 agar. 



> Leclainche et Vallee, Ann. de I'inst. Pasteur, 1900. 

 ' Martin, Ann. de I'inst. Pasteur, 1898. 



