622 MICROBIOLOGY OF THE DISEASES OF MAN AND ANIMALS. 



sometimes appear. It shows bipolar stain, decolorizes by Gram's method, produces no 

 spores, has no flagella, and is non-motile. 



The disease resembles anthrax in some general characteristics but 

 is easily distinguished by microscopic examination of the blood and 

 failure to find the large anthrax bacteria and by the fact that the blood 

 from the general circulation is apparently normal in haemorrhagic septi- 

 caemia. This disease also resembles symptomatic anthrax (blackleg) 

 but is easily distinguished in that external swellings are slight if present 

 at all and do not show gas, both of these features being characteristic of 

 blackleg. The bacillus of symptomatic anthrax may be recognized by 

 microscopic examination as so different from Bacterium bovisepticum 

 that there could be no mistaking one for the other. 



Little is known concerning elimination of this bacterium from the 

 diseased body and concerning methods of dissemination. Hence we are 

 very much in the dark when attempting to deal with the disease pro- 

 duced by it. 



Isolation and disinfection are to be recommended on general principles. 



LEPROSY.* 



Bacterium 



Leprosy is a disease almost as old as history itself but modern leprosy 

 cannot be definitely identified with the leprosy of the Old Testament, 

 and to day is found chiefly in oriental countries and in Norway, Iceland 

 and Russia. The disease is present in some of the provinces of Canada 

 and in the States of Louisiana, California and Minnesota, and practic- 

 ally limited to Scandinavians in the latter states. The natural incubation 

 period is difficult to ascertain but is probably a matter of months or years. 



Clinically there are two main types of the disease, the tubercular 

 or nodular and the anaesthetic types. In the first form, nodules develop 

 in the face or other parts of the body usually preceded by an erythematous 

 patch. The mucous membranes become affected more or less extensively 

 and the hair and eyebrows fall out. In the anaesthetic type after various 

 disturbances of sensation which may sometimes be followed by maculae 

 there develop areas of anaesthesia. Bullae, ulcers and necrosis may occur 

 with resulting deformities or again this type may exist for years without 

 leading to such results. 



* Prepared by Edward Fidlar. 



