title: The efficacy of a chitin synthesis inhibitor against field populations of organophosphate-resistant Aedes aegypti in Brazil.
abstract: The mosquito Aedes aegypti is the main focus of dengue control campaigns. Because of widespread resistance against conventional chemical insecticides, chitin synthesis inhibitors (CSIs) are considered control alternatives. We evaluated the resistance status of four Brazilian Ae. aegypti populations to both the organophosphate temephos and the pyrethroid deltamethrin, which are used in Brazil to control larvae and adults, respectively. All vector populations exhibited high levels of temephos resistance and varying rates of alterations in their susceptibility to pyrethroids. The effect of the CSI novaluron on these populations was also investigated. Novaluron was effective against all populations under laboratory conditions. Field-simulated assays with partial water replacement were conducted to evaluate novaluron persistence. Bioassays were continued until an adult emergence inhibition of at least 70% was attained. We found a residual effect of eight weeks under indoor conditions and novaluron persisted for five-six weeks in assays conducted in an external area. Our data show that novaluron is effective against the Ae. aegypti populations tested, regardless of their resistance to conventional chemical insecticides.
authors.affiliation: Laboratório de Fisiologia e Controle de Artrópodes Vetores, Instituto Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil.
authors.forename: Nathalia Giglio
authors.initials: NG
authors.lastname: Fontoura
authors.forename: Diogo Fernandes
authors.initials: DF
authors.lastname: Bellinato
authors.forename: Denise
authors.initials: D
authors.lastname: Valle
authors.forename: José Bento Pereira
authors.initials: JB
authors.lastname: Lima
mesh_terms: D000330:Aedes / Q000201:enzymology*; D000818:Animals; D001681:Biological Assay; D001938:Brazil; D002687:Chitin Synthase / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D003715:Dengue / Q000517:prevention & control / Q000635:transmission; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007303:Insect Vectors / Q000187:drug effects / Q000201:enzymology*; D007305:Insecticide Resistance; D009032:Mosquito Control / Q000379:methods*; D009570:Nitriles; D010671:Phenylurea Compounds / Q000494:pharmacology*; D011722:Pyrethrins; D000002:Temefos
chemical_list: D004791:Enzyme Inhibitors; D009570:Nitriles; D010671:Phenylurea Compounds; D011722:Pyrethrins; C017180:decamethrin; D002687:Chitin Synthase; D000002:Temefos; C471805:novaluron