Patterns of insecticide resistance and knock down resistance (kdr) in malaria vectors An. arabiensis, An. coluzzii and An. gambiae from sympatric areas in Senegal. Issue 1 (December 2016)

• Record Type: Journal Article
• Authors: Niang, El; Konaté, Lassana; Diallo, Mawlouth; Faye, Ousmane; Dia, Ibrahima
• Is Part Of: Parasites & vectors. Volume 9:Issue 1(2016)
• Page Start: 1
• Page End: 9
• Publication Date: 2016-12
• Subjects: Insecticide resistance -- kdr resistance -- Anopheles arabiensis -- Anopheles coluzzii -- An. gambiae; Parasitism -- Periodicals; Parasites -- Periodicals; Vector-pathogen relationships -- Periodicals; Animals as carriers of disease -- Periodicals; Insects as carriers of disease -- Periodicals; 616.96
• DOI: 10.1186/s13071-016-1354-3
• Languages: English
• ISSNs: 1756-3305

Abstract

Abstract Background Malaria vector control in Africa relies on insecticides targeting adult mosquito vectors via insecticide treated nets or indoor residual spraying. Despite the proven efficacy of these strategies, the emergence and rapid rise in insecticide resistance in malaria vectors raises many concerns about their sustainability. Therefore, the monitoring of insecticide resistance is essential for resistance management strategies implementation. We investigated thekdr mutation frequencies in 20 sympatric sites ofAn. arabiensis Patton, An. coluzzii Coetzee & Wilkerson andAn. gambiae Giles and its importance in malaria vector control by evaluating the susceptibility to insecticides in four representative sites in Senegal. Methods Sibling species identification andkdr mutation detection were determined using polymerase chain reaction on mosquitoes collected using pyrethrum sprays collection in 20 sites belonging to two transects with differential insecticide selection pressure. The World Health Organization (WHO) tube test was used to determine phenotypic resistance ofAn. gambiae s.l. to DDT, deltamethrin, lambdacyholothrin, permethrin, bendiocarb and malathion in four representative sites. Results The L1014Fkdr mutation was widely distributed and was predominant inAn. gambiae in comparison toAn. arabiensis andAn. coluzzii . The bioassay tests showed a general trend with a resistance to DDT and pyrethroids and a susceptibility to organophosphate and carbamate according to WHO thresholds. For deltamethrin and permethrin, the two most used insecticides, no significant difference were observed either between the two transects or between mortality rates suggesting no differential selection pressures on malaria vectors. The study of the KD times showed similar trends as comparable levels of resistance were observed, the effect being more pronounced for permethrin. Conclusions Our study showed a widespread resistance of malaria vectors to DDT and pyrethroids and a widespread distribution of the 1014Fkdr allele. These combined observations could suggest the involvement of thekdr mutation. The existence of other resistance mechanisms could not be ruled out as a proportion of mosquitoes did not harbour thekdr allele whereas the populations were fully resistant. The susceptibility to carbamate and organophosphate could be exploited as alternative for insecticide resistance management.