16S rRNA gene-based genetic diversity of Wolbachia strains infecting Anopheles gambiae s.s. and Anopheles coluzzii in Côte d’Ivoire

Abstract Wolbachia is an endosymbiont bacterium found Anopheles gambiae s.l., the main vector of malaria in Côte d’Ivoire. It’s a bacteria species that is involved in many metabolic reactions of its arthropods host. The interactions of this bacteria and its host depends on bacterial strain and arthropods host. Our study aims to analyze the genetic diversity of Wolbachiastrains infecting Anopheles gambiaecomplex in Côte d’Ivoire. Anopheles gambiae s.l. larvae were collected in Boundiali, Korhogo, Bouaké, Abidjan and Bingerville from November to December 2024 and reared in laboratory. At adult stage, the Anopheles gambiaecomplex were discriminated by specific allelic PCR. Then Wolbachia was screened from female of different species identified and confirmed by sequencing of 16S rRNA gene through sanger method. Evolutionary divergence of the 16S rRNA sequence was estimated using Kimura 2-parameter before phylogenetic tree construction. Overall, 74.57 % of Anopheles gambiae s.s., 21.73 % of Anopheles coluzzii and 3.46 % of hybrids were identified. The infection prevalence of Anopheles gambiaecomplex by Wolbachia depends on mosquito species with higher infection rate (25.84 %) in Anopheles coluzzii. than Anopheles gambiae s.s. (12.42 %). Phylogenetic analysis allowed the identification of different clones of the same Wolbachia strain, named wAnga_CI, which is clustered with supergroup B. Our results show a very low divergence, less than 1 %, between 16S rRNA sequences of wAnga_CI and these are divided into two haplotypes. Our results show that all species of Anopheles gambiae s.l. in Côte d’Ivoire are infected by the same strain of Wolbachia.