Evaluation of Temephos 50% CE on populations of Aedes aegypti (Diptera: Culicidae) in Trujillo, Venezuela

Abstract

Trujillo state, located in the Andean region of Venezuela, is considered to have a high incidence for dengue, besides coexisting with other tropical diseases such as leishmaniasis, malaria, and Chagas disease. The national program of dengue control includes the use of Temephos as the main larvicide, therefore the purpose of this study was to determine the lethal concentrations 50 and 95 to 50% temephos CE in Aedes aegypti populations from different centers of high dengue endemicity in Trujillo state. Four populations were selected (TE, HTO, PTO and MT), collected along a transect in the northeast-southeast direction of the city of Trujillo and evaluated following the WHO methodology. The LC₅₀ values for the four populations ranged between 0.0031 and 0.0317 ppm, and the LC₉₅ values between 0.0170 and 0.0567 ppm. The HTO, PTO and TR populations were similar, showing values up to ten times higher than those found in the reference population. The spatial distribution of these three populations and the topography of the city facilitate genetic exchange among them, which suggests performing continuous monitoring.