Insecticide resistance status of Aedes aegypti and Aedes albopictus mosquitoes in southern Benin, West Africa

Alphonse Keller Konkon; Germain Gil Padonou; Razaki Osse; Albert Sourou Salako; David Mahouton Zoungbédji; Haziz Sina; Arthur Sovi; Filemon Tokponnon; Rock Aïkpon; Herbert Noukpo; Lamine Baba-Moussa; Martin Codjo Akogbéto

doi:10.1186/s41182-023-00514-y

Insecticide resistance status of Aedes aegypti and Aedes albopictus mosquitoes in southern Benin, West Africa

Trop Med Health. 2023 Apr 21;51(1):22. doi: 10.1186/s41182-023-00514-y.

Authors

Alphonse Keller Konkon^{1

2}, Germain Gil Padonou^{3

4}, Razaki Osse^{3

5}, Albert Sourou Salako³, David Mahouton Zoungbédji^{3

4}, Haziz Sina^{4

6}, Arthur Sovi^{3

7

8}, Filemon Tokponnon³, Rock Aïkpon^{9

10}, Herbert Noukpo³, Lamine Baba-Moussa^{4

6}, Martin Codjo Akogbéto³

Affiliations

¹ Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Benin. konkonkelleralphonse@gmail.com.
² Faculté des Sciences et Techniques de l'Université d'Abomey-Calavi, Abomey-Calavi, Benin. konkonkelleralphonse@gmail.com.
³ Centre de Recherche Entomologique de Cotonou (CREC), 06 BP 2604, Cotonou, Benin.
⁴ Faculté des Sciences et Techniques de l'Université d'Abomey-Calavi, Abomey-Calavi, Benin.
⁵ École de Gestion et d'exploitation des Systèmes d'élevage de l'Université Nationale d'Agriculture de Porto-Novo, Porto-Novo, Benin.
⁶ Department of Biochemistry and Cellular Biology, Laboratory of Biology and Molecular Typing in Microbiology, University of Abomey-Calavi, Abomey-Calavi, Benin.
⁷ Faculty of Agronomy, University of Parakou, Parakou, Benin.
⁸ Faculty of Infectious and Tropical Diseases, The London School of Hygiene and Tropical Medicine, London, UK.
⁹ Ministère de la Santé, 08 BP 882, Cotonou, Benin.
¹⁰ Université Nationale des Sciences, Technologies, Ingénierie Et Mathématiques (UNSTIM), Abomey, Benin.

Abstract

Background: The emergence of insecticide resistance in Aedes mosquitoes could undermine efforts to control arboviruses. The present study aims to assess in some communes of Southern Benin, the susceptibility level of Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1894) to insecticides commonly used in public health, as well as mechanisms involved.

Methods: Females Ae. albopictus and Ae. aegypti collected in Ifangni, Porto-Novo, Avrankou, Adjarra and Kétou from June 2021 to October 2022, were exposed to: deltamethrin 0.05%, permethrin 0.75%, alpha-cypermethrin 0.05%, pirimiphos methyl 0.25% and bendiocarb 0.1%, following the standard WHO susceptibility tube test protocol. In some sites, pre-exposure to the synergist PBO was used to verify if pyrethroid resistance of populations of Aedes was mediated by oxidases.

Results: Full susceptibility to deltamethrin and permethrin was observed in all tested populations of Ae. albopictus. However, with alphacypermethrin, a suspected resistance was observed in Adjarra (94.67%), Ifangni (93%) and Porto-Novo (94%), and a resistance in Avrankou (83%). The PBO-alphacypermethrin tests performed, led to a full susceptibility (100%) in all four sites, which confirms the full involvement of oxidases in resistance of all tested populations of Ae. albopictus to alphacypermethrin. At the opposite, Aedes aegypti was either resistant or suspected of being resistant to all tested pyrethroids in all four sites, except in Ifangni where a full susceptibility to alphacypermethrin was observed. The full susceptibility of Ae. aegypti to bendiocarb and pirimiphos-methyl in all communes suggests that these two insecticides can be good candidates for an effective control of pyrethroid-resistant Aedes vector populations. Use of permethrin and deltamethrin could also be considered for controlling populations of Ae. albopictus.

Conclusion: Results of the present study will help guide strategy to implement for an effective control of Aedes vector populations in Benin.

Keywords: Aedes aegypti; Aedes albopictus; Benin; Insecticide resistance diagnostics.