Field evaluation of a smoke-generating formulation containing beta-cypermethrin against the dengue vector in Argentina.

Previous results from laboratory and prefield assays obtained by our laboratory indicated that the fumigant canister CIPEIN PF-7 (Bolate) a smoke-generating formulation containing 5% beta-cypermethrin, has excellent performance as an adulticide for Aedes aegypti control. A field trial was carried out to evaluate the effectiveness of CIPEIN PF-7 to control adult mosquitoes of Ae. aegypti inside houses. The trial was carried out in Colonia Delicia, a locality of 4,750 inhabitants, located in Misiones, a subtropical area in northeastern Argentina, an area highly infested with Ae. aegypti and at risk to dengue. One fumigant canister was applied in each house, which remained closed for 1 h and was then ventilated for 15 min by opening doors and windows. Taking into account the time spent in the fumigation activities, the rate of the treatment was around 20 houses per worker per day. Cages with adult mosquitoes and plastic cups with water containing mosquito larvae were put in various places of the houses. There was 100% initial mortality in each case after treatment with the fumigant canister. The residual effect showed 100% mortality of adults exposed 2 h for at least 3 days after treatment and 100% mortality of larvae 1 day after treatment. House and Breteau indices before the treatment were 51% and 106, respectively, falling to 23% and 44 after treatment. The potential for using this new tool in geographic areas very difficult to reach or as a quick alternative to control Ae. aegypti inside the houses, especially during dengue epidemics, is discussed.