ANTHRAX IN MAN. 307 



bility to anthrax. It is always communicated to him from 

 animals, and usually is seen among those whose trade leads 

 them to handle the carcases or skins of animals which have 

 died of the disease. It occurs in two principal forms, the 

 main difference between which is the site of entrance of 

 the organism into the body. In one, the path of entrance 

 is through cuts or abrasions in the skin, or through the hair 

 follicles. A local condition called a " malignant pustule " 

 develops, which may lead to a general infection. This 

 variety occurs chiefly among butchers and those who work 

 among hides (foreign ones especially). In Britain the 

 workers of the latter class chiefly liable are the hide-porters 

 and hide-workers in south-eastern London. In the other 

 variety of the disease, the site of infection is the trachea 

 and bronchi, and here a fatal result almost always follows. 

 The cause is the inhalation of dust or threads from wool 

 which has been taken from sheep dead of the disease, and 

 which has been contaminated with blood or secretions con- 

 taining the bacilli, these having afterwards formed spores. 

 From the fact that this variety occurs in the centres of the 

 wool-stapling trade (in England, chiefly in Yorkshire), it is 

 called " woolsorter's disease." 



(i) Malignant Pustule. This usually occurs on the 

 exposed surfaces the face, hands, forearms, and back, the 

 last being a common site among hide-porters. One to three 

 days after inoculation a small red painful pimple appears, 

 soon becoming a vesicle, which may contain clear or blood- 

 stained fluid, and is rapidly surrounded by an area of 

 intense congestion. Central necrosis occurs and leads to 

 the malignant pustule proper, which in its typical form 

 appears as a black eschar often surrounded by a ring of 

 vesicles, these in turn being surrounded by a congested area. 

 From this pustule as a centre, subcutaneous cedema spreads, 

 especially in the direction of the lymphatics ; the neighbour- 

 ing glands are enlarged. There is fever with general 

 malaise. On microscopic section of the typical pustule, 

 the central eschar is noticed to be composed of necrosed 

 tissue and degenerating blood cells ; the vesicles are 



