Aspectos operacionais do controle do Triatoma brasiliensis

vector control strategies against indigenous species is not easy, due to their capacity to reinvade treated premises from sylvatic ecotopes. between august 1996 and december 1997 we conducted a study on reinfestation of houses after spraying in a county in the state of ceará. of 277 houses examined, 113 (40.8%) were infested (21.7% intradomiciliary and 35.4% peridomiciliary). of the 433 triatominae collected, 207 were triatoma brasiliensis (49% of which intradomiciliary, with a mean of 1.8 insects/house) and 226 were triatoma pseudomaculata (97% peridomiciliary). the age structure of the two indicated a univoltine development cycle for t. brasiliensis and two cycles per year for t. pseudomaculata. four months after spraying with deltamethrin sc 25mg ia/m2, 9.7% of the houses were still positive, mainly with peridomestic infestations. intradomiciliary wall bioassays showed persistence of the insecticide up to 9 months after spraying. considering the high potential for recolonization of treated premises from sylvatic foci, we propose an operational strategy combining traditional evaluations and community-based surveillance with increased selective interventions and community education.