Vector Entomology. A search for natural infections of sandflies with Leishmania parasites in endemic areas of Salta, Argentina: a preliminary report

BARROSO, PAOLA ANDREA; MARCO, JORGE DIEGO; RUEDA, PEDRO; CAJAL, SILVANA PAMELA; BASOMBRÍO, MIGUEL ANGEL; TARANTO, NÉSTOR JUAN; HASHIGUCHI, YOSHIHISA

Studies on New and Old World Leishmaniasis and their transmission, with particular reference to Ecuador, Argentina and Pakistan

Kyowa Printing & Co. Ltd.

Lugar: Kochi, Japan; Año: 2004; p. 44 - 51

With the objective of a search for natural infections with Leishmania spp. in sandflies of the genus Lutzomyia, 514 flies were collected in endemic areas of American tegumentary leishmaniasis (ATL), in Río Blanco-Orán and Pichanal, in the north of Salta province, Argentina, between December 2002 and January 2003. The sandflies were sampled from the study sites where the causative agent of ATL was previously identified as Leishmania (Viannia) braziliensis by multilocus enzyme electrophoresis (MLEE). The captures were made from 8:30 p.m. to 10:30 p.m. with a Shannon trap, and the sandflies collected were maintained at low temperature (around 4ºC) until the next morning for search of Leishmania promastigotes in their guts. The identification of sandfly species was made, based on the observation of spermathecae, cibarial armatures and in some cases the male terminalia. Lutzomyia neivai, was the unique species collected in Río Blanco-Orán area and it was associated to both the primary forest and peridomestic-rural habitat with secondary vegetation. Both Lu. cortelezzii and Lu. neivai were caught under the peridomestic-periurban environment in Pichanal locality, being the first one the predominant species (90 %). Lu. neivai, Lu. cortelezzii and Lu. sallesi were identified from nine flies collected in the other study site, Profesor Salvador Mazza, where the vegetation is similar to other ATL-endemic areas, but no human cases are reported hitherto. In the present study, a total of 229 (58.1%) of the 394 female sandflies collected in Río Blanco-Orán and Pichanal were dissected and searched for Leishmania promastigotes under the microscope; but no natural infection was found. The distributions of the present two anthropophilic sandfly species, Lu. neivai and Lu. cortelezzii were overlapped with those of L. (V.) braziliensis. Further studies are necessary to incriminate the vector of ATL prevalent in Salta, Argentina.