Recent emergence of insensitive acetylcholinesterase in Chinese populations of the mosquito Culex pipiens (Diptera: Culicidae).

Feng Cui (1) , Michel Raymond (1) , Arnaud Berthomieu (1) , Haoues Alout (1) , Mylene Weill (1) , Chuan-Ling Qiao (2)

1 UMR ISEM - Institut des Sciences de l'Evolution de Montpellier
2 State Key Laboratory of Integrated Management of Pest Insects and Rodents

Organophosphate/carbamate target resistance has emerged in Culex pipiens L. (Diptera: Culicidae), the vector of Wuchereria bancrofti and West Nile virus (family Flaviviridae, genus Flavivirus) in China. The insensitive acetylcholinesterase was detected in only one of 20 samples collected on a north-to-south transect. According to previous findings, a unique mutation, G119S in the ace-1 gene, explained this high insensitivity. Phylogenetic analysis indicates that the mutation G119S recently detected in China results from an independent mutation event. The G119S mutation thus occurred at least three times independently within the Cx. pipiens complex, once in the temperate (Cx. p. pipiens) and twice in the tropical form (Cx. p. quinquefasciatus). Bioassays performed with a purified G119S strain indicated that this substitution was associated with high levels of resistance to chlorpyrifos, fenitrothion, malathion, and parathion, but low levels of resistance to dichlorvos, trichlorfon, and fenthion. Hence, it is possible that in China, dichlorvos, trichlorfon, and fenthion will still achieve effective control even in the presence of the G119S mutation.

Domaines: Sciences de l'environnement; Biodiversité et Ecologie

Feng Cui, Michel Raymond, Arnaud Berthomieu, Haoues Alout, Mylene Weill, et al.. Recent emergence of insensitive acetylcholinesterase in Chinese populations of the mosquito Culex pipiens (Diptera: Culicidae).. Journal of Medical Entomology, 2006, 43 (5), pp.878-83. ⟨10.1093/jmedent/43.5.878⟩. ⟨hal-01945532⟩