Insecticide Resistance in Aedes aegypti Mosquitoes: Possible Detection of kdr F1534C, S989P, and V1016G Triple Mutation in Benin, West Africa

Tatchémè Filémon Tokponnon; Razaki Ossè; Sare Dabou Zoulkifilou; Gbenouga Amos; Houessinon Festus; Gounou Idayath; Aboubakar Sidick; Louisa A Messenger; Martin Akogbeto

doi:10.3390/insects15040295

Insecticide Resistance in Aedes aegypti Mosquitoes: Possible Detection of kdr F1534C, S989P, and V1016G Triple Mutation in Benin, West Africa

Insects. 2024 Apr 22;15(4):295. doi: 10.3390/insects15040295.

Authors

Tatchémè Filémon Tokponnon^{1

2

3}, Razaki Ossè^{2

4}, Sare Dabou Zoulkifilou^{1

2}, Gbenouga Amos¹, Houessinon Festus^{1

2}, Gounou Idayath^{1

2}, Aboubakar Sidick², Louisa A Messenger^{5

6}, Martin Akogbeto²

Affiliations

¹ Ecole Polytechnique d'Abomey Calavi, Université d'Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin.
² Centre de Recherche Entomologique de Cotonou, Ministère de la Santé, Cotonou 06 BP 2604, Benin.
³ Centre Béninois de la Recherche Scientifique et de l'Innovation (CBRSI), Cotonou BP 1665, Benin.
⁴ Ecole de Gestion et d'Exploitation des Systèmes d'Elevage, Université Nationale d'Agriculture, Kétou BP 44, Benin.
⁵ Department of Disease Control, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK.
⁶ Department of Environmental and Occupational Health, School of Public Health, University of Nevada, Las Vegas, NV 89154, USA.

Abstract

Epidemics of arboviruses in general, and dengue fever in particular, are an increasing threat in areas where Aedes (Ae.) aegypti is present. The effectiveness of chemical control of Ae. aegypti is jeopardized by the increasing frequency of insecticide resistance. The aim of this study was to determine the susceptibility status of Ae. aegypti to public health insecticides and assess the underlying mechanisms driving insecticide resistance. Ae. aegypti eggs were collected in two study sites in the vicinity of houses for two weeks using gravid Aedes traps (GATs). After rearing the mosquitoes to adulthood, female Ae. aegypti were exposed to diagnostic doses of permethrin, deltamethrin and bendiocarb, using Centers for Disease Control and Prevention (CDC) bottle bioassays. Unexposed, un-engorged female Ae. aegypti were tested individually for mixed-function oxidase (MFO), glutathione-S-transferase (GST) and α and β esterase activities. Finally, allele-specific PCR (AS-PCR) was used to detect possible kdr mutations (F1534C, S989P, and V1016G) in the voltage-gated sodium channel gene in insecticide-exposed Ae. aegypti. Most traps were oviposition positive; 93.2% and 97% of traps contained Ae. aegypti eggs in the 10^ème arrondissement of Cotonou and in Godomey-Togoudo, respectively. Insecticide bioassays detected resistance to permethrin and deltamethrin in both study sites and complete susceptibility to bendiocarb. By comparison to the insecticide-susceptible Rockefeller strain, field Ae. aegypti populations had significantly higher levels of GSTs and significantly lower levels of α and β esterases; there was no significant difference between levels of MFOs. AS-PCR genotyping revealed the possible presence of 3 kdr mutations (F1534C, S989P, and V1016G) at high frequencies; 80.9% (228/282) of the Ae. aegypti tested had at least 1 mutation, while the simultaneous presence of all 3 kdr mutations was identified in 13 resistant individuals. Study findings demonstrated phenotypic pyrethroid resistance, the over-expression of key detoxification enzymes, and the possible presence of several kdr mutations in Ae. aegypti populations, emphasizing the urgent need to implement vector control strategies targeting arbovirus vector species in Benin.

Keywords: 10ème arrondissement of Cotonou; Aedes aegypti; Benin; Godomey-Togoudo; detoxification enzymes; kdr mutations; pyrethroid resistance.

Grants and funding

This work was partly funded by Researchers in the Entomological Research Center of Cotonou.