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3. It should be demonstrated that naturally or experimentally 

 infected flies can maintain the infection in the laboratory through 

 the complete life cycle of the parasite. 



4. It should be demonstrated experimentally that the sand fly can 

 transmit Leishmania by bite. 



5. Leishmania should be isolated from wi ld-caught sand flies and 

 shown to be indistinguishable from the parasite causing disease in man 

 in the same place. 



In the case of Lu. diabolica , the first four criteria have been 

 met as fol lows: 



1. Lutzomyia diabolica were found in man-biting collections in 

 the vicinities of autochthonous human case sites of cutaneous 

 leishmaniasis in south central Texas. In addition, adult females were 

 collected in light traps in the back yard of a patient in D'Hanis, 

 Texas. These adults fed readily on the author's arm immediately after 

 capture (see Chapter 2). Lu . diabol ica is the only anthropophil ic 

 species of sand fly known from Texas (Young and Perkins, 1984). 



2. The known distribution of Lu_. diabol ica is in accord with that" 

 of autochthonous human cases of leishmaniasis in south central Texas 

 (Fig. 2-29, page 73, Chap. 2). Collection records indicate that Lu. 

 diabolica is sufficiently abundant in these areas to maintain the 

 transmission cycle in nature (Table 2-1, page 51, Chap. 2). Semi- 

 weekly New Jersey light trap collections from the case site in 

 D'Hanis, Texas, indicate that the sand fly is present there from early 

 May through early December. 



3. It has been demonstrated experimentally that _Lu. diabol ica can 

 maintain L. mexicana (strain WR-411) infections for life, through the 

 complete extrinsic life cycle of the parasite. 



