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bioRxiv · 10.1101/2023.02.02.526745

PermaNet(R) Dual, a new deltamethrin-chlorfenapyr mixture net, shows improved efficacy against pyrethroid-resistant Anopheles gambiae sensu lato in southern Benin

Abstract

Pyrethroid-chlorfenapyr nets have demonstrated improved entomological and epidemiological impact in trials across Africa. This is driving increased demand for this novel net class in malaria endemic countries. PermaNet(R) Dual is a new deltamethrin-chlorfenapyr net developed by Vestergaard Sarl to provide more options to malaria control programmes. We performed an experimental hut trial to evaluate the efficacy of PermaNet(R) Dual against wild, free-flying pyrethroid-resistant Anopheles gambiae sensu lato in Cove, Benin. PermaNet(R) Dual induced superior levels of mosquito mortality compared to a pyrethroid-only net and a pyrethroid-piperonyl butoxide net both when unwashed (77% with PermaNet(R) Dual vs. 23% with PermaNet(R) 2.0 and 56% with PermaNet(R) 3.0, p<0.001) and after 20 standardised washes (75% with PermaNet(R) Dual vs. 14% with PermaNet(R) 2.0 and 30% with PermaNet(R) 3.0, p<0.001). Using a provisional non-inferiority margin defined by the World Health Organisation, PermaNet(R) Dual was also non-inferior to a pyrethroid-chlorfenapyr net that has demonstrated improved public health value (Interceptor(R) G2), for vector mortality (79% vs. 76%, OR=0.854, 95% CIs: 0.703-1.038) but not for blood-feeding protection (35% vs. 26%, OR=1.445, 95% CIs: 1.203-1.735). PermaNet(R) Dual presents an additional option of this highly effective net class for improved control of malaria transmitted by pyrethroid-resistant mosquitoes.

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BibTeXRIS

Syme, T., N'dombidje, B., Gbegbo, M., Todjinou, D., Ariori, V., de Vos, P., Pigeon, O., Ngufor, C.. 2023-02-03. PermaNet(R) Dual, a new deltamethrin-chlorfenapyr mixture net, shows improved efficacy against pyrethroid-resistant Anopheles gambiae sensu lato in southern Benin. https://doi.org/10.1101/2023.02.02.526745

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