Anopheles leesoni Evans 1931, a Member of the Anopheles funestus Group, Is a Potential Malaria Vector in Cameroon

Abstract

Background: Understanding the biology of Anopheles malaria vector species is essential to planning effective and sustainable malaria control strategies in endemic countries. This study reported the implication of Anopheles leesoni in malaria transmission in Cameroon, Central Africa. Methods: Mosquitoes were collected in three localities from May 2015 to March 2018 using electric aspirators and Centers for Disease Control light traps (CDC-LT). Anopheles funestus sensu lato (s.l.) mosquitoes were identified as species using polymerase chain reaction assay (PCR). Furthermore, Plasmodium falciparum infection status was determined using the enzyme-linked immunosorbent assay (ELISA) method. Results: A total of 12,744 Anopheles mosquitoes were collected by electric aspirator (N = 4844) and CDC-LT (N = 7900). Anopheles funestus s.l. (86.95%) was the major species and the main malaria vector in rural savannah and rural forest sites followed by A. gambiae s.l. (13.05%) whereas in urban areas, A. gambiae s.l. was by far the most abundant representing 91.45% of Anopheles mosquitoes collected. Two members of the A. funestus group were identified among 1389 analysed by PCR: 1307 A. funestus sensu stricto (s.s.) (94.10%) and 82 A. leesoni (5.9%). Plasmodium falciparum infection rate was 21.04% in A. funestus s.s. For the first time, A. leesoni was found positive for P. falciparum (infection rate: 10.98%) in Cameroon. Conclusion: A very high P. falciparum infection rate was observed in this study in A. funestus s.s., highlighting its high implication in malaria transmission in Cameroon. Furthermore, the detection of P. falciparum infection in A. leesoni calls for more attention towards this neglected vector species.