CHAPTER 4 

 EXPERIMENTAL TRANSMISSION OF Leishmania mexicana 

 BY BITES OF Lutzomyia diabolica (HALL) AND 

 Lutzomyia shannon i (DYAR) WITH NOTES ON THE 

 EXTRINSIC DEVELOPMENT OF THE PARASITE 



Introduction 



From a medical perspective, the most important aspect of the 

 biology of a sand fly is whether or not it can transmit leishmaniasis 

 (Kil 1 ick-Kendrick, 1978). Making such a determination is time 

 consuming and usually requires field and laboratory investigations of 

 the insect's biology, followed by labor-intensive experimentation in 

 vector-parasite-host relationships. Consequently, experimental 

 transmissions by bites of sand flies are infrequently demonstrated. A 

 historical review of the incrimination of the major vectors of 

 leishmaniasis is presented in Chapter 1. 



The WHO Scientific Working Group on the Leishmaniases (1977) gave 

 long-term, high priority to the establishment of complete life cycles 

 of Leishmania in the laboratory by using natural vertebrate and 

 invertebrate hosts. This is necessary to determine the dynamics and 

 mechanics of transmission and to study the developmental morphology 

 and physiology of the parasites in these hosts. 



At present, five species of Leishmania , L. donovani , J_. chagasi , 

 J., infantum , L tropica , and L mexicana ssp. have been 

 experimentally transmitted to human volunteers or laboratory animals 

 by bites of about a dozen sand fly species (Kil 1 ick-Kendrick, 1981a). 



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