94 DIFFERENTIA!^ DIAGNOSIS 



to the mistaking of it for poisoning, cerebral apoplexy, pul- 

 monar\' congestion, heat apoplexy, death from lightning, or 

 acute gastro-intestinal inflammation. The affection known as 

 corn stalk disease is not infrequentl}' taken for anthrax and 

 vice versa. In all of these cases the doubt following the post- 

 mortem can be easily settled by a bacteriological examination 

 which, with genuine anthrax, will reveal the presence of 

 Baderiiim antliracis. 



There are, however, certain specific diseases from which 

 anthrax must be differentiated. The more important of these 

 are sj'mtomatic anthrax (black leg), malignant oedema, and 

 septicaemia hemorrhagica. Rabies is not infrequently taken 

 for anthrax. If the diagnosis cannot be determined bj- the 

 anatomical changes (which can be relied upon only in some- 

 what typical cases) the positive diagnosis can be made only with 

 the finding of the anthrax bacteria. In animals just dead, where 

 decomposition has not begun, these organisms can usually be 

 found in properly stained cover-glass preparations made di- 

 rectly from the blood or tissues. After decomposition begins to 

 take place, a putrefactive organism, that is not easily distin- 

 guished from that of anthrax, often appears in the tissues. It 

 is, therefore, necessary in such cases to resort to culture meth- 

 ods before a positive statement can be made. As the bacilli of 

 malignant oedema and symptomatic anthrax are anaerobes, 

 they will not develop in aerobic cultures such as on slant 

 agar or in bouillon. The bacterium of septicaemia hemor- 

 rhagica being a small oval organism is easily told from that of 

 anthrax. Bacillus subtilis has occasionally been taken for the 

 anthrax bacterium ; but it is readily separated morphologially 

 and in cultures, especially in bouillon, where subtilis forms a 

 firm, wrinkled membrane over the surface of the liquid which 

 remains clear while the anthrax organisms grow in flocculi 

 within the medium. It is important to recognize the possi- 

 bility of error, if the conditions restrict the examination to the 

 study of the micro.scopic preparations. 



§80. Protective inoculation. Toussaint was the first to 

 make use of protective inoculations in anthrax. He heated 

 defibrinated anthrax blood to a temperature of 50 to 55° C. for 



Digitized by Microsoft® 



