Control trial of Lutzomyia longipalpis s.l. in the Island of Margarita, Venezuela
The incidence of the American visceral leishmaniasis (AVL) in the Island of Margarita, a major tourist centre in Venezuela, has been increasing between 1998 and 2001. Lutzomyia longipalpis s.l. is the recognized vector, which was found naturally infected with Leishmania spp, indistinguishable from the parasites recovered from dogs and children. In 1999–2000, we conducted a control trial in Santa Ana del Valle and Las Cabreras, which have similar epidemiological and ecological conditions. The trial was based on intradomestic residual spraying of -cyhalotrin, E.C., 25 mg/m2 and spatial fogging of fenitrothion around the houses at 30 g/ha. Sandfly abundance was recorded using Centers for Disease Control (CDC) traps indoors and outdoors. We found significantly reduced sandfly populations in the target locality. Wall bioassays showed that the residual effect of the insecticide lasts for about 3 months. We believe that indoor spraying with -cyhalotrin three times a year, at a dose slightly greater than 25 mg/m2, might reduce the L. longipalpis s.l. population to a level low enough for achieving a significant reduction of the indoor transmission, thus protecting small children from the disease.
Document Type: Research Article
Affiliations: 1: Universidad de Carabobo, Facultad de Ciencias de la Salud, Centro Nacional de Referencia de Flebótomos (CNRFV), BIOMED, Núcleo Aragua, Maracay, Venezuela 2: Dirección de Vigilancia Epidemiológica y Control Sanitario Ambiental, Ministry of Health and Social Development, Venezuela 3: Dirección Regional de Salud, Estado Nueva Esparta, Venezuela 4: Instituto de Biomedicina, UCV/MSDS, Caracas, Venezuela
Publication date: December 1, 2003