A cytochrome P450 DNA marker in a major mosquito vector of malaria indicates that pyrethroid resistance reduces bednet efficacy.

Abstract Elucidating the genetic basis of metabolic resistance to insecticides in malaria vectors is crucial prolonging effectiveness insecticide-based control tools including long lasting insecticidal nets (LLINs). Here, we show that cis -regulatory variants cytochrome P450 gene, CYP6P9b , are associated with pyrethroid African vector Anopheles funestus . A DNA-based assay designed track this occurs near fixation southern Africa but not West/Central Africa. Applying demonstrate, using...

Insecticide resistance poses a serious threat to insecticide-based interventions in Africa. There is fear that escalation could jeopardize malaria control efforts. Monitoring of cases aggravation intensity and its impact on the efficacy tools crucial predict consequences resistance.

New insecticides have recently been produced to help control pyrethroid-resistant malaria vectors including the pyrrole, chlorfenapyr. Monitoring susceptibility of mosquito populations against this new product and potential cross-resistance with current is vital for better resistance management. In study, we assessed status major Anopheles gambiae funestus chlorfenapyr across Africa explored known pyrethroid markers. Efficacy 100 µg/ml An. from five Cameroonian locations, Democratic Republic...

Abstract Metabolic resistance to insecticides is threatening malaria control in Africa. However, the extent which it impacts transmission remains unclear. Here, we investigated association between a marker of glutathione S-transferase mediated metabolic and Plasmodium infection field population Anopheles funestus s.s. comparison A296S-RDL target site mutation. The 119F-GSTe2 resistant allele was present southern (Obout) (56%) central (Mibellon) (25%) regions Cameroon whereas 296S-RDL...

Metabolic resistance threatens the sustainability of pyrethroid-based malaria control interventions. Elucidating fitness cost and potential reversal metabolic is crucial to design suitable management strategies. Here, we deciphered associated with CYP6P9a (P450-mediated resistance) in major African vector Anopheles funestus. Reciprocal crosses were performed between a pyrethroid susceptible (FANG) resistant (FUMOZ-R) laboratory strains hybrid showed intermediate resistance. Genotyping...

Monitoring cases of insecticide resistance aggravation and the effect on efficacy control tools is crucial for successful malaria control. In this study, intensity major vectors from Uganda was characterised its impact performance various insecticide-treated nets elucidated. High to discriminating concentration (DC), 5× DC, 10× DC pyrethroids observed in both Anopheles funestus gambiae Mayuge Busia leading significant reduced long-lasting insecticidal (LLINs) including piperonyl butoxide...

Evaluating the susceptibility of malaria vectors to new WHO-recommended products is a key step before large-scale deployment. We mapped profile Anopheles funestus neonicotinoids across Africa and established diagnostic doses acetamiprid imidacloprid with acetone + MERO as solvent. Indoor resting An. were collected in 2021 Cameroon, Malawi, Ghana Uganda. Susceptibility clothianidin, was evaluated using CDC bottle assays offsprings field-caught adults. The L119F-GSTe2 marker genotyped assess...

Deciphering the evolutionary forces controlling insecticide resistance in malaria vectors remains a prerequisite to designing molecular tools detect and assess impact on control tools. Here, we demonstrate that 4.3kb transposon-containing structural variation is associated with pyrethroid central/eastern African populations of vector Anopheles funestus. In this study, analysed Pooled template sequencing data direct identify an insertion containing putative retro-transposon intergenic region...

Metabolic resistance to insecticides threatens malaria control. However, little is known about its fitness cost in field populations of vectors, thus limiting the design suitable management strategies. Here, we assessed association between glutathione S-transferase GSTe2-mediated metabolic and life-traits natural Anopheles funestus. A total 1200 indoor resting blood-fed female An. funestus (F0) were collected Mibellon, Cameroon (2016/2017), allowed lay eggs individually. Genotyping F1...

The scale-up in the distribution of long-lasting insecticidal nets (LLINs) and indoor residual spraying has significantly reduced malaria burden mortality. However, insecticide resistance, among other factors, is responsible for a recent rebound transmission 2015–2016, threatening progress so far made. As contribution towards understanding patterns resistance its mechanism field we characterized population Anopheles gambiae (s.l.) from Gounougou, Guinea savanna north/central Cameroon. Indoor...

Abstract Background Aggravation of insecticide resistance in malaria vectors is threatening the efforts to control by reducing efficacy insecticide-based interventions hence needs be closely monitored. This study investigated intensity two major An. funestus sensu stricto (s.s.) and gambiae lato (s.l.) collected southern Ghana assessed bio-efficacy several long-lasting insecticidal nets (LLINs) against these mosquito populations. Methods The susceptibility profiles Anopheles s.s. s.l....

New insecticides with a novel mode of action such as neonicotinoids have recently been recommended for public health by WHO. Resistance monitoring requires robust protocol to monitor the development resistance in natural populations. In this study, we comparatively used three different solvents assess susceptibility malaria vectors across Africa.Mosquitoes were collected from May July 2021 agricultural settings Cameroon (Njombe-Penja, Nkolondom, and Mangoum), Democratic Republic Congo...

The increasing reports of resistance to pyrethroid insecticides associated with reduced efficacy pyrethroid-only interventions highlight the urgency introducing new non-pyrethroid-only control tools. Here, we investigated performance piperonyl-butoxide (PBO)-pyrethroid [Permanet 3.0 (P3.0)] and dual active ingredients (AI) nets [Interceptor G2 (IG2): containing pyrethroids chlorfenapyr Royal Guard (RG): pyriproxyfen] compared net Sentry (RS) against pyrethroid-resistant malaria vectors in Cameroon.

Abstract Metabolic resistance to pyrethroids is jeopardizing the effectiveness of insecticide-based interventions against malaria. The complexity Africa-wide spatio-temporal evolution molecular basis this resistance, major genetic drivers should be detected improve management. Here, we demonstrated that a single amino acid change G454A in cytochrome P450 CYP9K1 drives pyrethroid Anopheles funestus vector East and Central Africa. Polymorphism analysis revealed drastic reduction diversity gene...

Abstract Gaining a comprehensive understanding of the genetic mechanisms underlying insecticide resistance in malaria vectors is crucial for optimising effectiveness insecticide-based vector control methods and developing diagnostic tools management. Considering heterogeneity metabolic major vectors, implementation tailored management strategies essential successful control. In this study, we provide evidence demonstrating that two highly selected mutations tandemly duplicated cytochrome...

Abstract Insecticide resistance is jeopardising malaria control efforts in Africa. Deciphering the evolutionary dynamics of mosquito populations country-wide essential for designing effective and sustainable national subnational tailored strategies to accelerate elimination efforts. Here, we employed genome-wide association studies through pooled template sequencing compare four eco-geographically different major vector, Anopheles funestus, across a South North transect Cameroon, aiming...

Anopheles funestus mosquitoes currently contribute more than 85% of ongoing malaria transmission events in south-eastern Tanzania, even though they occur lower densities other vectors, such as arabiensis. Unfortunately, the species ecology is minimally understood, partly because difficulties laboratory colonization. This study describes first observations An. swarms possibly heralding new opportunities for control.Using systematic searches by community-based volunteers and expert...

Elucidating the complex evolutionary armory that mosquitoes deploy against insecticides is crucial to maintain effectiveness of insecticide-based interventions. Here, we deciphered role a 6.5-kb structural variation (SV) in driving cytochrome P450-mediated pyrethroid resistance malaria vector, Anopheles funestus. Whole-genome pooled sequencing detected an intergenic SV between duplicated CYP6P9a/b P450s pyrethroid-resistant through translocation event. Promoter analysis revealed 17.5-fold...

Resistance is threatening the effectiveness of insecticide-based interventions in use for malaria control. Pinpointing genes associated with resistance crucial evidence-based management targeting major vectors. Here, a combination RNA-seq based genome-wide transcriptional analysis and RNA-silencing vivo functional validation were used to identify key insecticide DDT DDT/permethrin cross-resistance across Africa. A cluster glutathione-S-transferase from epsilon group found be overexpressed...

Abstract Background Increased intensity of pyrethroid resistance is threatening the effectiveness insecticide-based interventions to control malaria in Africa. Assessing extent this aggravation and its impact on efficacy these tools vital ensure continued major vectors. Here we took advantage 2009 2014 data from Malawi establish escalation 2021 assessed various bed nets performance. Methods Indoor blood-fed wild female Anopheles (An) mosquitoes were collected with an electric aspirator...

Metabolic mechanisms conferring pyrethroid resistance in malaria vectors are jeopardizing the effectiveness of insecticide-based interventions, and identification their markers is a key requirement for robust management. Here, using field-lab-field approach, we demonstrated that single mutation G454A P450 CYP9K1 driving major vector Anopheles funestus East Central Africa. Drastic reduction diversity was observed Ugandan samples collected 2014, with selection predominant haplotype (G454A at...

Despite the increased report of insecticide resistance in malaria vectors, its impact on mosquito's life-traits after exposure to insecticide-treated nets remains under investigated. Here, we assessed effects PermaNet 2.0 several life traits An. gambiae s.l. and funestus field mosquitoes Cameroon.