STUDY OF PHLEBOTOMINES (DIPTERA, PSYCHODI DAE) IN FOCUS OF VISCERAL LEISHMANIASIS IN BRAZIL

Introduction In the Americas, Lutzomyia longipalpis has been incrimina ted as the vector of visceral leishmaniasis in almost all the areas in which this disease has been reported. The notification of human cases of visceral leishmaniasis and the presence of dogs with an appearance suggestive of the disease in the county of Corumba, Mato Grosso do Su l State, Brazil, led us to undertake an entomological investigation in this area, for the purpose of identifying the phlebotomine vector Mat erial and Method The county of Corumba is located in the Pantanal regi on and its urban area is situated at 18 degrees 59' 44'' South and 57 degrees 39' 16'' West. The research project was carried our in peri an d intradomiciliary environments, in three urban districts, one of whic h was central and the other two on the outskirts, and in a cave situat ed outside the urban perimeter Most of the captures were made weekly w ith light automatic traps, in the period from February 1984 to Decembe r 1986. Meteorological data for this period were obtained from the cit ys meteorological station and those for the period from 1925 to 1982 f rom the literature. Results The urban phlebotomine fauna consisted of eight species and was similar to that of the cave, except that in the latter the species were more abundant. Lutzomyia cruzi was predominant in the peri and intradomiciliary environments. Its prevalence in the central district was of 90.3% and lower in the outskirts. Lu. forattin ii presented considerable prevalence (39.0%) in one of the outlying di stricts too. In the cave, Lu. corumbaensis was the predominant species , followed by Lu. sordellii, Lu. forattinii, Lu. peresi and Lu. cruzi. The impact of the climatic condition and the action of insecticides i n the urban area on the frequence of the species, as well as the use o f the cave as a breeding ground by the phlebotomines, in view of the c hanges in the sex rare, are commented. Data on anthropophily and captu res of Lu. forattinii using dog bait have been added. Conclusion The p redominance of Lu. cruzi in the urban area; the great prevalence of Lu . forattinii in most of the outlying areas studied and the anthropophi ly of this latter species, as well as the strong affinity of these spe cies with Lu. longipalpis, the main vector of visceral leishmaniais in other areas of rite Americas, suggest the participation of both in th e transmission of the disease in Corumba.