Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

Volume 18, Number 9—September 2012

Dispatch

Multiple-Insecticide Resistance in Anopheles gambiae Mosquitoes, Southern Côte d’Ivoire

Constant V.A. Edi, Benjamin G. Koudou, Christopher M. Jones, David Weetman, and Hilary RansonComments to Author 
Author affiliations: Liverpool School of Tropical Medicine, Liverpool, UK (C.V.A. Edi, B.G. Koudou, C.M. Jones, D. Weetman, H. Ranson); Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, Abidjan, Côte d’Ivoire (C.V.A. Edi, B.G. Koudou); and Université d’Abobo-Adjamé, Abidjan (B.G. Koudou)

Main Article

Table 2

Association between genotype and mosquito survival after insecticide exposure*

Insecticide No. tested Status No. No. per genotype
Frequency†
Odds ratio§ p value
LL LF FF 1014F‡
DDT 73 Alive 48 2 7 39 88.5 4 0.02
Dead 25 2 10 13 72
Permethrin 88 Alive 44 1 12 31 84.1 1.23 0.82
Dead 44 3 12 29 79.5
Deltamethrin 89 Alive 45 1 12 32 84.4 0.82 0.86
Dead 44 2 9 33 85.2
GG GS SS 119S¶
Bendiocarb 86 Alive 49 0 49 0 50 100 0.40 × 10–12
Dead 37 25 12 0 16.2
Fenitrothion 100 Alive 50 0 50 0 50 1,176 0
Dead 50 48 2 0 2

*F and L represent mutant resistant alleles (phenylalanine) and wild-type alleles (leucine), respectively; S and G represent mutant resistant alleles (serine) and wild-type alleles (glycine), respectively. No resistant homozygotes GG were found among the 186 mosquitoes genotyped for Ace-1R by restriction fragment length polymorphism (a subset of 48 was further screened by using the TaqMan assay; congruence between the 2 methods was 100%).
†The frequencies were calculated for each insecticide and mosquito status (alive/dead) after exposure.
‡1014F represent the kdr frequencies.
§Genotypic odds ratios (ORs) are shown because these exceed allelic ORs for DDT (recessive model), bendiocarb, and fenitrothion (both overdominant models), and are similar for permethrin and deltamethrin. For bendiocarb and fenitrothion absence of GG genotypes in the “Alive” group means that ORs are infinity, therefore ORs are shown if one GG was present. F and L represent mutant resistant alleles (phenylalanine) and wild-type alleles (leucine), respectively; S and G represent mutant resistant alleles (serine) and wild-type alleles.
¶119S represents the Ace-1R frequencies.

Main Article

TOP