ANTHRAX. 55 



pig. The Algerian sheep has a high degree of immunity, as has the 

 white rat. The brown rat is^quite susceptible. The disease in man 

 chiefly occurs among those working with hides, wool or meat of 

 infected cattle. The two chief types in man are: (i) Malignant 

 pustule and (2) Woolsorter's disease. An intestinal type is also 

 recognized. Malignant pustule results from the inoculation of an 

 abrasion or cut; thus it frequently shows on the arms and the backs of 

 those unloading hides. It first appears as a pimple, the center of 

 which becomes vesicular, then necrotic. A ring of vesicles surrounds 



FIG. 17. Anthrax bacilli growing in a chain and exhibiting spores. 

 (Kolle and Wassermann.} 



this central eschar and a zone of congestion the vesicles. The lymphatics 

 soon become inflamed as well as neighboring glands. The bacilli 

 are found especially in the vesicles or the lymphatics. If the pustule is 

 not excised and death occurs, there is not much enlargement of the 

 spleen and the bacteria are not abundant in the kidneys, etc., as with 

 animals. Man seems to die from a toxaemia rather than a septicaemia. 



In woolsorter's disease there is great swelling and oedema of the 

 bronchial and mediastinal glands. The lungs show oedema, which 

 about the bronchi is hemorrhagic. 



The bacillus is 5 to 8// by i to i i/2fi. It has square cut or concave 

 ends and is often found in chains. It is Gram positive. Colonies, by 

 interlacing waves of strings of bacteria, show Medusa head appearance. 



