Phenotypic and Molecular Characterization African Malaria Vector Anopheles Funestus

Phenotypic and molecular characterization of pyrethroid resistance escalation in the African malaria vector Anopheles funestus Cameroon-wide Hervé Raoul TAZOKONG, Magellan Tchouakui, Gadji Mahamat, Stevia Ntadoun Tchamga, Tatiane Assatse, Steve Valdi Djova, Benjamin D. Menze, Ebai Terence, Micareme Tchoupo, Leon M. J. [...] falciparum escaping detection by RDTs • Drug and Insecticide resistance • Climate change • Disruption of services due to COVID-19 WHO, 2023 48% off track Malaria burden in Cameroon 2000-2022 WHO, 20234 Rationale Characterizing the intensity of insecticide resistance is crucial for better resistance management strategies and before it is potentially too late, to mitigate its public heal [...] 2022) Intensification of insecticide resistance in An. [...] 2023) Cameroon5 General Objective Characterize the level of resistance, assess impact on control tools and investigate its molecular mechanisms in the major malaria vector Anopheles funestus in Cameroon6 Methodology 1/2 Period: Aug.2020-Dec. [...] Map of Cameroon showing sites where indoor mosquito were collected 1x, 5x and 10x DC Synergist assay Cone Assay Various bed nets7 Methodology 2/2 DNA F0 and F1 samples MIX - ID species cocktail funestus (Koekemoer et al. [...] funestus Table1: synergist assay with PBO Efficacy of LLINs against high resistant strain of An. [...] funestus • Increased susceptibility with PBO indicating the implication of cytochrome P450s • Drastic loss in efficacy with pyrethroids-only net but good performance with PBO nets CI= Confidence Interval, PBO= Piperonyl butoxide11 Association of the L119F-GSTe2 mutation and pyrethroid resistance intensity in Mibellon mosquitoes Alive Dead Alive Dead Alive Dead 0 20 40 60 80 100 Genotype f [...] 001 • The L119F-GSTe2 mutation was associated with the ability to survive 1x DC permethrin but not 5x and 10x doses • In contrast, a negative correlation of this mutation was noticed with a-cypermethrin 10x • L119F-GSTe2 may impact permethrin-based nets but not the alphacypermethrin-based nets12 Transcription profile of resistant genes in Mibellon population Carb2514 GSTe2 CYP9K1 CYP6P5 CYP3 [...] funestus populations studied leading to a drastic loss of efficacy of pyrethroids only nets • Aggravation of resistance may be driven by metabolic enzymes suggesting the effectiveness of PBO-based nets in these areas • This study underscores the role of molecular surveillance of malaria vectors using existing resistant markers as key component of vector control strategies • Whole genom [...] WONDJI Manuscript: “Nationwide susceptibility profiling of Anopheles funestus from Cameroon reveals escalating pyrethroid resistance and reduced bed nets efficacy”, in prep