Leishmaniasis in the lowlands of Bolivia. Entomological studies on sandflies of the "Valle del Sacta". Tropical Carrasco of the Department of Cochabamba.

Abstract

Up to 1987, through the LEISHBOL project (CEE-STD1) studies on sandflies were performed in the rain forests of Yapacani, a region of the Department of Santa Cruz. In another set of studies, also carried out within the LEISHBOLPE project (CEE-STD2), sandflies were studied in the rain forests of the "Valle del Sacta, Prov. Carrasco" of the Departament of Cochabamba, to determine the composition of the species, its density, the anthropophilic species, and its infection by flagellates. 18 species were identified, from those collected in the Valle del Sacta, one of which was a new species now being described as Lutzomyia lerayi n-sp. Only 7 species are common with those identified in Yapacani, in spite of the proximity and of the apparent similarity of the biotopes. Lu. shawi was the only species captured practically year round, and highest densities were identified in October with 7.6 "females/hour/shannon trap". The lowest monthly density occurred in July with "0.2 female/hour/shannon trap." In relation to the altitudinal density of Lu. shawi, it was higher at 5 meters (5.5 females/night/CDC in October) than at 1 meter (2.3 females/night/CDC-trap in November) above ground level. The following species was detected as anthropophilic: Lu. shawi, Lu. amazonensis, Lu. evangelistai and Lu. sherlocki. 4.5% (7 of 154) of Lu. shawi were found to be infected by flagellates in suprapiloric position. The composition of the sandfly species of Valle del Sacta is different than that of Yacapani. The most important species of Valle del Sacta is Lu. shawi, instead of Lu. yucumensis of Yapacani.