Efficacy of Pyrethroid–Pyriproxyfen and Pyrethroid–Chlorfenapyr Long-Lasting Insecticidal Nets (LLINs) for the Control of Non-<i>Anopheles</i> Mosquitoes: Secondary Analysis from a Cluster Randomised Controlled Trial (cRCT)
Constantin J. Adoha,
Arthur Sovi,
Boulais Yovogan,
Bruno Akinro,
Manfred Accrombessi,
Edouard Dangbénon,
Esdras M. Odjo,
Hermann Watson Sagbohan,
Casimir Dossou Kpanou,
Gil G. Padonou,
Louisa A. Messenger,
Clément Agbangla,
Corine Ngufor,
Jackie Cook,
Natacha Protopopoff,
Martin C. Akogbéto
Affiliations
Constantin J. Adoha
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Arthur Sovi
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
Boulais Yovogan
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Bruno Akinro
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
Manfred Accrombessi
Faculty of Infectious and Tropical Diseases, Disease Control Department, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
Edouard Dangbénon
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
Esdras M. Odjo
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Hermann Watson Sagbohan
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Casimir Dossou Kpanou
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
Gil G. Padonou
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Louisa A. Messenger
Faculty of Infectious and Tropical Diseases, Disease Control Department, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
Clément Agbangla
Faculté des Sciences et Techniques, Université d’Abomey-Calavi, Abomey-Calavi 01 BP 526, Benin
Corine Ngufor
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
Jackie Cook
Medical Research Council (MRC) International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
Natacha Protopopoff
Faculty of Infectious and Tropical Diseases, Disease Control Department, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
Martin C. Akogbéto
Centre de Recherche Entomologique de Cotonou, Cotonou 06 BP 2604, Benin
The efficacy of a vector control tool in reducing mosquito biting is crucial for its acceptability. The present study compared the vector density of Culex spp. And Mansonia spp. across clusters, which received two dual-active ingredient (a.i.) long-lasting insecticidal nets (LLINs) and a standard pyrethroid-only LLIN, and assessed the seasonality of these mosquito genera. A total of 85,723 Culex spp. and 144,025 Mansonia spp. were caught over the study period. The density of Culex and Mansonia was reduced in all three arms over the study period. There was no evidence of a significant reduction in the indoor or outdoor density of Culex spp. in either dual-a.i. LLIN arm as compared to the standard pyrethroid-only net arm. A similar trend was observed with Mansonia spp. A high density of Culex spp. was found both in rainy and dry seasons, while for Mansonia spp., this was mainly observed during the rainy season. These results suggest that the novel insecticides in the dual-a.i. LLINs did not have an additional impact on these species and that pyrethroids might still be effective on them. Further work is required to determine whether these species of mosquitoes have resistance to the insecticides tested in this trial.
