20 Kas 2024 Çarşamba
Knockdown resistance mutation and haplotype diversity in wild population of Anopheles gambiae s.l. from Gombe state, Nigeria
Abstract : Vector controls are important strategies in the reduction of disease transmission. Currently, malaria vector control relies on the use of long-lasting insecticide-treated bednets at the national level and Indoor Residual Spray in some rural communities. However, Anopheles mosquitoes have developed insecticide resistance to chemical insecticides in several malaria endemic countries including Nigeria and Gombe state specifically. Here, we characterized Anopheles gambiae s.l. from Akko and Kaltungo LGAs for the occurrence of Knock dawn resistance mutation. Anopheles larvae were collected using standard dipper of 350ml, in eight communities and reared to adult stage at normal room temperature and relative humidity in the laboratory. A susceptibility test was carried out on Adult emerged female Anopheles. Out of which a total of 96 An. gambiae s.l. sub-samples of 53 alive and 41 death were identified using Coetzee's key and further validated using Santolomaza's standard PCR protocol to distinguish sibling species. West Africa Knock down resistance (Kdr) mutation (L1014F) among the species was determined and the haplotype diversity was also computed from the sequences derived after DNA amplification of the target Voltage Gated Sodium Chanel (VGSC) gene mutation. Phylogenetic analysis was employed to identify their relationships with known Anopheles species from the NCBI Genbank. Molecular identification of 94 Anopheles gambiae s.l. sub-samples revealed the occurrence of An. gambiae s.s, An. coluzzii and An. arabiensis with allelic frequencies of 16.7, 15.1, and 0.23% respectively. The haplotype diversity (1.000) indicated high diversity in Lapandintai populations. The study has established insecticide resistance associated with L1014F mutation of the Kdr gene. The detection of Kdr mutation in wild populations of An. gambiae s.l. from Gombe State is a threat on the efficacy of pyrethroids impregnated LLINs currently deployed for malaria vector control. Hence, the results provide some insights that would guide the stakeholders in the implementation of appropriate vector control interventions.