CHAPTER XXXII 



BACILLUS OF SYMPTOMATIC ANTHRAX, BACILLUS OF MALIGNANT 



EDEMA, BACILLUS AEROGENES CAPSULATUS, BACILLUS 



BOTULINUS 



BACILLUS OF SYMPTOMATIC ANTHRAX 



{Bacillus anthracis symptomatici, Rauschbrand, Charbon sym,ptoinatique, 

 Sarcophysematos hovis) 



Symptomatic anthrax is an infectious disease occurring chiefly 

 among sheep, cattle, and goats. It is colloquially spoken of as " quarter- 

 evil" or "blackleg." The disease has never been observed in man. It 

 was formerly, and is often to-day, confused with true anthrax, largely 

 because of a superficial similarity between the clinical symptoms of 

 the two maladies. Bacteriologically, the two microorganisms are in 

 entirely different classes. 



Geographically, symptomatic anthrax is of wide distribution and 

 infection is usually through the agency of the soil in which the bacillus 

 is present, probably in the form of spores which may retain viability 

 and pathogenicity for several years. 



Morphology and Staining. — The bacillus of symptomatic anthrax is 

 a bacillus with rounded ends, somewhat shorter and relatively thicker 

 than the bacillus of malignant edema, being about four to six micra 

 long, and five-tenths to six-tenths micra wide. It is usually seen singly 

 and never forms long chains. The bacillus in its vegetative form is 

 actively motile and possesses numerous flagella placed about its 

 periphery. In artificial media it forms spores which are oval, broader 

 than the rod itself, and placed near, though never actually at, the 

 end of the bacillary body. This gives the bacillus a racket-shaped 

 appearance. 



It is readily stained with the usual anilin dyes, but is decolorized by 

 Gram's method of staining. 



Cultivation. — The bacillus is a strict anaerobe. It was obtained in 

 pure culture first by Kitasato.' Under anaerobic conditions it is easily 



1 Kitasato, Woch. f. Hyg., 1889. 

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