The knockdown resistance mutation and knockdown time in anopheles gambiae collected from Mali evaluated through a bottle bioassay and a novel insecticide-treated net bioassay

Rebecca T. Trout Fryxell, Stephanie N. Seifert, Yoosook Lee, Adama Sacko, Gregory C Lanzaro, Anthony Cornel

Research output: Contribution to journalArticle

2 Scopus citations


Successful malaria management in Mali includes the use of pyrethroids and insecticide-treated nets (ITNs) for mosquito control; however, management is threatened by the spread of insecticide resistance detected via the knockdown resistance (kdr) allele. In a preliminary study, we compared the knockdown times of Anopheles gambiae from Mali using a novel ITN bioassay and the World Health Organization (WHO) bottle bioassay. Additionally, the frequency and relationship between kdr genotypes, molecular forms, and pyrethroid resistance were analyzed. The S molecular form was predominant and accounted for 76 of the assayed population. Both kdr resistant alleles, West Africa resistant (kdr-w) and East Africa resistant (kdr-e), were observed. There was no significant difference in knockdown time based on kdr genotype or molecular form of individual mosquitoes, but mosquitoes in the ITN bioassay homozygous for the kdr-w allele were knocked down significantly faster than those in the WHO bottle bioassay. The ITN bioassay provides an additional indicator of insecticide efficacy because ITNs, frequently used within homes, are the most common form of vector control and malaria prevention, and the ITN bioassays can evaluate seasonal field effects.

Original languageEnglish (US)
Pages (from-to)119-122
Number of pages4
JournalJournal of the American Mosquito Control Association
Issue number2
StatePublished - Jun 2012



  • Anopheles gambiae
  • bioassay
  • insecticide resistance
  • insecticide-treated nets
  • knockdown resistance
  • Mali

ASJC Scopus subject areas

  • Insect Science
  • Public Health, Environmental and Occupational Health
  • Ecology, Evolution, Behavior and Systematics

Cite this