Dominance and Diversity of Anopheles gambiae s.l (Female Mosquitoes) Collected from Six Local Government Areas in Adamawa State, Northeastern Nigeria

Abstract

Malaria continues to pose a formidable health challenge, particularly in regions where Anopheles mosquitoes are highly effective vectors for disease transmission. Hence the objective of the paper was to assess the dominance and diversity of Anopheles gambiae s.l (adult female mosquitoes) collected from six Local Government Areas in Adamawa State, North-eastern Nigeria using Coetzee’s identification key. The morphological identification revealed that Anopheles gambiae s.l was significantly the dominant species across all the areas studied, ranging from 97.3% in Hong to 99.7% in Gombi of all identified species, with 1.67% Anopheles pretoriensis identified in Hong LGA only. The presence of Anopheles pretoriensis in Hong LGA and its absence in other LGAs indicates geographical variations in species distribution. Molecularly, Anopheles coluzzii was the dominant sibling species observed across all Local Government Areas (LGAs), with its presence ranging from 66.7% in Mubi South to 83.3% in Mubi North, Gombi, Jada, and Mayo-Belwa of all identified Anopheles gambiae sensu lato (s.l). While a few samples of Anopheles gambiae and Anopheles arabiensis were identified, these were not found in all LGAs. Therefore, Anopheles gambiae s.l emerged as the dominant species identified morphologically, while molecularly, Anopheles coluzzii was the most prevalent sibling species for Anopheles gambiae s.l found in all six (6) LGAs. To mitigate the transmission risk of malaria, it is imperative to implement a multifaceted vector control strategy that effectively targets both exophilic and endophilic mosquito species.