Genus : Mycobacterium 

 Mycobacterium leprae (G. A. Hansen) Lehman and Neumann 



Insects concerned: Chlorops ( Musca ) leprae; Chlorops 

 vomitoria; the house fly, Mu3ca domes tica ; Sarcoptes 

 scabei ; Sarcophaga pallinervis , Sarcophaga barbata; 

 Yolucella o"besa ; Luc ilia sp. ; Stomoxys calci trans ; the 

 mosquito, Aedes aegypti ; and probably the "bedbug, Cimex 

 lectularius ; the mite, Demodex ; and the cockroach, Peri - 

 planeta americana . 



Mycobacterium leprae is the causative organism of lepro- 

 sy. As early as 1872, Hansen observed small rodshaped 

 bacilli lying within the "lepra cells." The leprosy bacil- 

 lus has never with certainty been cultivated on artificial 

 media. Furthermore, very little is known concerning the 

 method of its transmission. It is conceivable, however, 

 that in some instances the bacilli may be transferred from 

 one person to another by insects. 



Rosenau (1927) writes concerning the role of insects 

 in the transmission of leprosy: 



"The evidence is reviewed by Nuttall, who says: 

 'It appears that Linnaeus and Rolander considered 

 that Chlorops ( Musca ) leprae was able to cause 

 leprosy by its bite. ■ Blanchard and Corrodor 

 tell of flies in connection with leprosy. Flies 

 frequently gather in great numbers on the leprous 

 ulcers and then visit and bite other persons. An 

 observation by Boek of the presence of Sarcoptes 

 s cabe i in a case of cutaneous leprosy led Joly to 

 conclude that these parasites might at times serve 

 as carriers of the infection . . . Carrasquillo of 

 Bogota found the bacillus of Hansen in the intesti- 

 nal contents of flies. The British Leprosy Com- 

 mission investigated the possible role played by 

 insects with entirely negative results. "Wherry 

 . . . found that the fly Chlorops vomitoria took 

 up enormous numbers of lepra bacilli from the 

 carcass of a leper rat and deposited them with 

 their feces, but the bacilli apparently do not 

 multiply in flies, as the latter are clear of 

 bacilli in less than kS hours. Larvae of Chlorops 

 vomitoria hatched out in the carcass of a leper 

 rat become heavily infested with lepra bacilli. 

 If such larvae are removed and fed on uninfected 

 meat they soon rid themselves of most of the 

 lepra bacilli. A fly, Musca domestica , caught on 



