Species composition, infection rate and detection of resistant alleles in Anopheles funestus (Diptera: Culicidae) from Lare, a malaria hotspot district of Ethiopia

• Published in: Malaria Journal
• Main Authors: Delelegn Woyessa, Evangelia Morou, Nadja Wipf, Nsa Dada, Konstantinos Mavridis, John Vontas, Delenasaw Yewhalaw
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2023
• Subjects: Anophelus funestus; Resistant allele; Genotyping; Secondary malaria vectors; Single nucleotide polymorphisms; Ethiopia; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1186/s12936-023-04667-3; https://doaj.org/article/25580521ebcf4193b119d0eb038b9c62

Abstract Background Anopheles funestus, which is considered as secondary vector of malaria in Ethiopia, is known to have several morphologically indistinguishable (sibling) species. Accurate identification of sibling species is crucial to understand their biology, behaviour and vector competence. In this study, molecular identification was conducted on the Ethiopian An. funestus populations. Moreover, insecticide resistance mechanism markers were detected, including ace N485I, kdr L1014F, L1014S, and CYP6P9a TaqMan qPCR was used to detect the infective stage of the parasite from field collected adult female An. funestus populations. Methods Adult female mosquito collection was conducted from Lare, Gambella Regional State of Ethiopia between June 2018 to July 2020 using CDC light traps and HLC. Sub-samples of the morphologically identified An. funestus mosquitoes were molecularly identified using species-specific PCR, and the possible presence of insecticide resistance alleles was investigated using TaqMan qPCR (N485I-Ace-1), PCR-Sanger sequencing (L1014F-kdr), and PCR–RFLP (CYP6P9a resistance allele). Following head/thorax dissection, the TaqMan qPCR assay was used to investigate the presence of the infective stage Plasmodium parasite species. Results A total of 1086 adult female An. funestus mosquitoes were collected during the study period. All sub-samples (N = 20) that were morphologically identified as An. funestus sensu lato (s.l.) were identified as An. funestus sensu stricto (s.s.) using species- specific PCR assay. The PCR–RFLP assay that detects the CYP6P9a resistance allele that confers pyrethroid resistance in An. funestus was applied in N = 30 randomly selected An. funestus s.l. specimens. None of the specimens showed a digestion pattern consistent with the presence of the CYP6P9a resistance allele in contrast to what was observed in the positive control. Consequently, all samples were characterized as wild type. The qPCR TaqMan assay that detects the N485I acetylcholinesterase-1 mutation conferring ...