Transfluthrin eave-positioned targeted insecticide (EPTI) reduces human landing rate (HLR) of pyrethroid resistant and susceptible malaria vectors in a semi-field simulated peridomestic space

Autor: Lorenz Hofer, Ummi Abdul Kibondo, Sarah J. Moore, Adam Saddler, Mgeni Mohamed Tambwe
Rok vydání: 2021
Předmět:
Zdroj: Malaria Journal, Vol 20, Iss 1, Pp 1-12 (2021)
Malaria Journal
ISSN: 1475-2875
DOI: 10.1186/s12936-021-03880-2
Popis: BackgroundVolatile pyrethroids (VPs) are proven to reduce human–vector contact for mosquito vectors. With increasing resistance to pyrethroids in mosquitoes, the efficacy of VPs, such as transfluthrin, may be compromised. Therefore, experiments were conducted to determine if the efficacy of transfluthrin eave-positioned targeted insecticide (EPTI) depends on the resistance status of malaria vectors.MethodsRibbons treated with 5.25 g transfluthrin or untreated controls were used around the eaves of an experimental hut as EPTI inside a semi-field system. Mosquito strains with different levels of pyrethroid resistance were released simultaneously, recaptured by means of human landing catches (HLCs) and monitored for 24-h mortality. Technical-grade (TG) transfluthrin was used, followed by emulsifiable concentrate (EC) transfluthrin and additional mosquito strains. Generalized linear mixed models with binomial distribution were used to determine the impact of transfluthrin and mosquito strain on mosquito landing rates and 24-h mortality.ResultsEPTI treated with 5.25 g of either TG or EC transfluthrin significantly reduced HLR of all susceptible and resistantAnophelesmosquitoes (Odds Ratio (OR) ranging from 0.14 (95% Confidence Interval (CI) [0.11–0.17], P P Anopheles arabiensis(Mbita strain) compared to the susceptibleAnopheles gambiae(Ifakara strain) (OR 1.50 [95% CI 1.18–1.91]P P An. arabiensis(Kingani strain) (OR 2.29 [95% CI 1.78–2.94]P P = 0.75). Finally the EC EPTI was equally effective against the susceptibleAn. gambiae(Kisumu strain) and the resistantAn. gambiae(Kisumu-kdr strain) (OR 0.98 [95% CI 0.74–1.30]P = 0.90).ConclusionsTransfluthrin-treated EPTI could be useful in areas with pyrethroid-resistant mosquitoes, but it remains unclear whether stronger resistance to pyrethroids will undermine the efficacy of transfluthrin. At this dosage, transfluthrin EPTI cannot be used to kill exposed mosquitoes.
Databáze: OpenAIRE
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