Bacillus Anthracis 401 



The animals most frequently affected are cows and sheep. 

 Among laboratory animals, white mice, house-mice, guinea- 

 pigs, and rabbits are highly susceptible; dogs, cats, most 

 birds, and amphibians are immune. White rats are infected 

 with difficulty. Man is slightly susceptible, the disease in 

 the human species usually being a local affection "malig- 

 nant carbuncle" commonly succeeded by a general fatal 

 infection. 



Anthrax was one of the first infectious diseases proved to 

 depend upon a specific micro-organism. As early as 1849 



Fig. 123. Bacillus anthracis; showing the capsules. From a case of 

 human infection. Magnified 1000 diameters (Schwalve). 



Pollender* discovered small rod-shaped bodies in the blood 

 of animals suffering from anthrax, but the exact relation 

 which they bore to the disease was not pointed out until 

 1863, when Davaine,| by a series of interesting experiments, 

 proved their etiologic significance to most unbiased minds. 

 The final confirmation of Davaine's conclusions and actual 

 proof of the matter rested with Koch,J who, observing that 

 the bacilli bore spores, cultivated them successfully outside 

 the body, and produced the disease by the inoculation of 

 pure cultures. 



* "Vierteljahrsschr. fur ger. Med.," Bd. vin, 1855. 

 t "Compte-rendu," Ivii, 1863. 

 t "Beitrage zur Biol. d. Blauzen," 1876. n. 

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