Evaluation of residual and fumigant effects of Deltamethrin WG250 on different surfaces against Anophels stephensi for malaria control

Abstract

Malaria is one of the public health problem in southern Iran. The main activity of vector control is indoor residual spraying using pyrethrpids. The aims of study was to evaluate the biological assays of deltamethrin WG250 at different surfaces of wall. The persistency of deltamethrin WG250 at 25 mg/m2 was studied on different local surfaces of rooms such as plaster and mud surfaces (sorbent) as well as wooden and thatch roofs (as non-sorbent). Contact bioassays were carried out using WHO standard cones and lab-bred sugar-fed, 48-72 h old females of Anopheles stephensi (Iranshahr strain). In contact bioassays carried out on sprayed surfaces for 150 days. Deltamethrin WG250 (25 mg/m2) caused 43.43-100.0% on sorbent surfaces and 61.11-100.0% on non-sorbent surfaces and persist about 3.5 months in the environmental condition of Saravan district. The fumigant bioassay of deltamethrin WG250 revealed 50-100% mortalities after one month.