title: Pyrethroid resistance reduces the efficacy of space sprays for dengue control on the island of Martinique (Caribbean).
abstract: BACKGROUND
  Dengue fever is reemerging on the island of Martinique and is a serious threat for the human population. During dengue epidemics, adult Aedes aegypti control with pyrethroid space sprays is implemented in order to rapidly reduce transmission. Unfortunately, vector control programs are facing operational challenges with the emergence of pyrethroid resistant Ae. aegypti populations.
  
  
  RESULTS
  To assess the impact of pyrethroid resistance on the efficacy of treatments, applications of deltamethrin and natural pyrethrins were performed with vehicle-mounted thermal foggers in 9 localities of Martinique, where Ae. aegypti populations are strongly resistant to pyrethroids. Efficacy was assessed by monitoring mortality rates of naturally resistant and laboratory susceptible mosquitoes placed in sentinel cages. Before, during and after spraying, larval and adult densities were estimated. Results showed high mortality rates of susceptible sentinel mosquitoes treated with deltamethrin while resistant mosquitoes exhibited very low mortality. There was no reduction of either larval or adult Ae. aegypti population densities after treatments.
  
  
  CONCLUSIONS
  This is the first documented evidence that pyrethroid resistance impedes dengue vector control using pyrethroid-based treatments. These results emphasize the need for alternative tools and strategies for dengue control programs.
authors.affiliation: Institut de Recherche pour le Développement (IRD), UR016 CCPV/UMR MIVEGEC, Montpellier, France. sebastien.marcombe@ird.fr
authors.forename: Sébastien
authors.initials: S
authors.lastname: Marcombe
authors.forename: Frédéric
authors.initials: F
authors.lastname: Darriet
authors.forename: Michel
authors.initials: M
authors.lastname: Tolosa
authors.forename: Philip
authors.initials: P
authors.lastname: Agnew
authors.forename: Stéphane
authors.initials: S
authors.lastname: Duchon
authors.forename: Manuel
authors.initials: M
authors.lastname: Etienne
authors.forename: Marie Michèle
authors.initials: MM
authors.lastname: Yp Tcha
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chandre
authors.forename: Vincent
authors.initials: V
authors.lastname: Corbel
authors.forename: André
authors.initials: A
authors.lastname: Yébakima
mesh_terms: D000330:Aedes / Q000187:drug effects*; D000818:Animals; D003715:Dengue / Q000453:epidemiology* / Q000517:prevention & control*; D004351:Drug Resistance; D005260:Female; D006801:Humans; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects; D008395:Martinique / Q000453:epidemiology; D009032:Mosquito Control / Q000379:methods*; D009570:Nitriles / Q000494:pharmacology; D011722:Pyrethrins / Q000494:pharmacology*; D016019:Survival Analysis
chemical_list: D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin