Topical insecticide treatments to protect dogs from sand fly vectors of leishmaniasis

We compared the susceptibility of sand fly vectors to four topical insectic ide treatments applied to domestic dogs, a reservoir of human leishmaniasis . Dogs were exposed to sand flies pretreatment and at I week, I month, and 2 months posttreatment. Sand fly bloodfeeding and survival rate of both fed and unfed flies were significantly reduced by the permethrin, deltamethrin , and fenthion treatments, but diazinon had no effect. The survival rate of bloodfed sand flies was reduced by up to 86% with deltamethrin collars. Th e antifeeding effect suggests that deltamethrin collars may be recommended to dog owners to protect their pets from sandfly-borne diseases. The combin ed effects on sand fly feeding and survival indicate that epidemiologic, co mmunity-based trials are warranted to test whether deltamethrin collars cou ld reduce the incidence of canine and, hence, human leishmaniasis.