280 CLINICAL BACTERIOLOGY. 



ment of leprosy in animals has thus far not succeeded. 

 The only observations that can be considered as positive 

 are those of Melcher and Ortmann, in which, after inocu- 

 lation of the anterior chamber of the eye, general infection 

 developed in rabbits ; but these are interpreted by most 

 observers as indicating that in the case or cases from 

 which the infecting material was obtained there existed 

 mixed infection with leprosy and tuberculosis, and that the 

 inoculated animals died of tuberculosis. All of the attempts 

 at inoculation of human beings have proved equally unsuc- 

 cessful, or at least not above criticism. Danielsen, who inoc- 

 ulated himself and others with nodular masses, blood, etc., 

 from leprous patients, obtained completely negative results. 

 On the other hand, the experiments of Arning terminated 

 positively ; this observer succeeded in transmitting leprosy 

 to a prisoner condemned to death. This case has, how- 

 ever, been seriously doubted, as the period of incubation 

 was strikingly short, being only sixteen months, whereas 

 the whole course of the disease covered only five years, and 

 as, besides, the inoculated person was a member of a race 

 highly susceptible to leprosy, and cases of leprosy had 

 already occurred in his family. 



Bacteriologic Diagnosis. Cover-slip preparations are 

 made from the contents and the tissue-juice of leprous 

 nodules, and are stained in precisely the same way as tuber- 

 cle-bacilli. Great care must be taken in the process of 

 decolorization. The sections of leprous tissue are not per- 

 mitted to remain for so long a time in the staining solution 

 as sections of tissue containing tubercle-bacilli ; half an hour 

 is quite sufficient. 



In most cases of leprosy, as R. Koch was the first to ob- 

 serve, the nasal mucus contains leprosy-bacilli. These are 

 derived from areas of ulcerated or swollen mucous mem- 

 brane on the cartilaginous portion of the nasal septum. 

 The bacilli may, however, be present when such visible 

 changes are absent. 



Heredity of Leprosy. According to Baumgarten, lep- 

 rosy, like tuberculosis, is transmissible by inheritance. If 

 this opinion is correct, a long period of latency must be as- 

 sumed for the inherited leprosy -bacilli, as the disease never 

 appears before the second or the third year of life. 



Prophylaxis. The best prophylaxis unquestionably 

 consists in isolation of leprous patients in special hospitals. 



