[Evaluating two pyrethroids in dengue vector control in Putumayo, Colombia].

OBJECTIVE Evaluating the efficacy of two pyrethroid insecticides on Aedes aegypti, thereby providing useful information for decision-making in controlling dengue. METHODS The effect on A. aegypti of ultra low volume (ULV) highcis-Permethrin (Depe) and ss-cypermethrin pyrethroids in a smoke-generating formulation (Bolate) was evaluated in 16 blocks in the town of Puerto Leguizamo, Putumayo, between July and December 2004. Their efficacy was measured by the mortality of mosquitoes kept in sentinel cages set in different parts of the households and weekly follow-up of the number of mosquitoes and the presence of larvae. RESULTS There was an 80% reduction in mosquito density on the day after insecticide treatment for both insecticides. Mosquitoes became displaced from inside the houses to outside them after the insecticides had been applied. In spite of the insecticides' immediate impact, a maintained reduction in mosquito density throughout the 5 weeks' evaluation was not observed, probably due to the emergence of adults from deposits which had not been treated. CONCLUSION These insecticides showed higher than 80% efficacy in reducing A. aegypti mosquito density and they constitute an alternative for dengue control.