An attempt to control Phlebotomine sand flies (Diptera: Psychodidae) by residual spraying with deltamethrin in a Colombian village

Abstract

An attempt was made to control phlebotomine sand flies biting indoors in a rural community near Cali, Colombia, using the residual insecticide "K-Othrine" (deltamethrin) sprayed on the inside walls of houses. Twelve houses were divided into matched pairs based on physical characteristics, one house in each pair being left untreated while the inside walls of the other were sprayed with 1% deltamethrin at a concentration of 500 mg a.i./m2. Sand flies were sampled each week using protected human bait and sticky trap collections for four months after spraying. The number of sand flies (Lutzomyia youngi) collected on sticky traps was significantly lower (P = 0.004) in the untreated houses than in the treated ones with which they were matched. This difference was not significant for L. columbiana; the other anthropophilic species were not present in large numbers. The numbers collected on human bait in treated and untreated houses were not significantly different for either species. Activity of the insecticide as determined by contact bioassays remained high throughout the study and failure to control the insects was attributed to two factors: the tendency of sand flies to bite before making contact with the insecticide and the fact that the number of sand flies that entered houses represented a relatively small proportion of the population in the wooded areas surrounding the settlement in the study.

Field evaluation of alphacypermethrin in indoor residual spraying for leishmaniasis control in an endemic area, northern Morocco

“…Alexander et al . [13] also found that residual spraying of walls with delthamethrin in a Colombian village surrounded by forest had no perceptible effect on the number of sand flies entering houses; although the insecticidal activity of the treated surfaces was undiminished during the study period. While other authors reported that residual pyrethroid spraying reduces sand fly indoor density in various localities in South America [14-16] and China [17] probably, because of their repulsive effect.…”

Leishmaniasis sand fly vector density reduction is less marked in destitute housing after insecticide thermal fogging

“…Insecticide control trials for New World sand flies have been carried out using organophosphates: Malathion [19]; organochlorines: DDT [20,21] and pyrethroids: cyfluthrin [22], cypermethrin [23,24], deltamethrin [25-30], lambdacyhalothrin [31-33]. Methods of insecticide application for SF control have included: fogging [19,22,34], residual spraying [21,23-27,31-33], insecticide diffusion devices [35], insecticide treated nets [28,29] and curtains [30]. In general, these studies have shown that insecticide application at the household level seems to be the most effective SF control method [7], because it can suppress both SF abundance [7] and CL transmission over short [36] and long term [37] time scales.…”

Investigation of Habitat Effects on the Spatial Distribution of Lutzomyia shannoni Across Heterogeneous Environments, With Note of Respective Mosquito Species Compositions

“…Understanding of sand ßy habitat and presumed adult resting areas are central components to the management strategies described for many phlebotomines and mosquitoes (Perich et al 1993, Alexander et al 1995, Robert and Perich 1995, Hubbard et al 2005, Trout et al 2006, Trout et al 2007.…”