Distribution of Organophosphate and Carbamate Resistance in Culex pipiens quinquefasciatus (Diptera: Culicidae) in West Africa

Abstract

The distribution of organophosphate and carbamate resistance was investigated in 33 samples of Culex pipiens quinquefasciatus Say from 25 cities in Côte d'Ivoire and Burkina Faso. Organophosphate resistance levels were higher in Côte d'Ivoire than in Burkina Faso. Chlorpyrifos resistance ratios at LC95 ranged from 4 to 30 times in Côte d'Ivoire and from 3 to 6 times in Burkina Faso. For temephos, ratios ranged from 3 to 18 and from 1 to 2, respectively. Of 27 samples from Côte d'Ivoire, 25 also displayed cross resistance to carbamates as shown by a mortality plateau in bioassays with propoxur and carbosulfan (similar to chlorpyrifos). Cross resistance to organophosphates and carbamates was caused by an insensitive acetylcholinesterase allele (AceR). This gene was absent from Burkina Faso, except in Niangoloko near the Côte d'Ivoire border. Organophosphate resistance also was associated with the presence of A2-B2 overproduced esterases which had higher frequencies in Côte d'Ivoire (75-100%) than in Burkina Faso (40-50%). Two other esterases with the same electrophoretic mobility as C2 from Puerto Rico and B1 from California were identified for the 1st time in West Africa. "C2" was widespread, whereas "B1" was present in only a few mosquitoes from Côte d'Ivoire. These differences in resistance patterns should be taken into consideration in planning urban mosquito control strategies within 2 countries.

Insecticide Resistance Allele Frequencies in Anopheles gambiae before and after Anti-Vector Interventions in Continental Equatorial Guinea

“…gambiae M and S populations in Cô te d'Ivoire, southern Benin, and Burkina Faso. [32][33][34][35][36] Similar to the distribution of kdr alleles in continental west Africa, the ace-1 R allele was far more prevalent in the S (32%) than the M (3.6%) molecular form. 36 In Cô te d'Ivoire, ace-1 R allele frequencies have reached levels as high as 30.9% and 35.2% in M and S molecular forms, respectively.…”

Efficacy of Alpha-Cypermethrin and Lambda-Cyhalothrin Applications to Prevent Aedes Breeding in Tires

“…The resistant strain of A. gambiae (VKPR), originating from Burkina Faso, was already strongly resistant to permethrin when collected in the field and has been maintained under constant permethrin selection at each generation (23). The resistant strain of C. quinquefasciatus (BKPER) was collected in Côte d'Ivoire and has also been maintained under continuous selection with permethrin (24). Both are homozygous for the kdr gene (25, 26) with a 40-fold resistance factor (by topical application) (20).…”

Caracterização de resistência a inseticidas em populações da subfamilia Triatominae (Hemiptera:Reduviidae), vetores de Trypanosoma cruzi Chagas, 1909

“…CHANDRE et al, 1997CHANDRE et al, , 1998CHEIKH et al, 1998;GONZÁLEZ et al, 1999;WHIRTH et al, 2000;CAMPOS e ANDRADE, 2001;N'GUESSAN et al, 2003;YUAN et al, 2003).…”