Molecular characterization and potentiality of Anopheles coluzzii in disease transmission in different communities in Ughelli North lga, Delta State, Nigeria

Abstract

A thorough understanding of the malaria vector’s dynamics is a crucial strategy for preventing mosquito bites and vector control. This study assessed the species composition, wing length and biting behavior with respect to seasons in Ughelli North LGA, Delta State, Nigeria. CDC light traps were used to capture mosquitoes hourly, indoors and outdoors in four settlements (Ugono Orogun, Orhomuru Orogun, Emonu Orogun and Ovara Orogun) for 10 months (May 2022 – February 2023). Mosquitoes collected outdoor (187) and indoor (138) were significantly different (p<0.05), with most abundant indoor recorded in June and July (5.25 ± 0.48 respectively), and outdoor in June (6.75 ± 0.48). Monthly variation in mosquito species was not significant (F = 0.71, df = 9, p = 0.695). The biting peaks of mosquitoes in the outdoor and indoor were observed between the hours of 8 – 9 pm respectively, also 3 – 4 am for indoor and 4 – 5 am for outdoor mosquitoes. Furthermore, all Anopheles mosquitoes collected were Anopheles gambiae sensu lato and confirmed molecularly to species level as Anopheles coluzzii. Mosquitoes outdoor had wing length significantly longer  p<0.05) than the mosquitoes obtained indoor and this may justify the reason for more outdoor mosquitoes. More mosquitoes were recorded in the wet months (F = 9.70, p = 0.0002) than in dry months. In conclusion, in order to lessen the prevalence of malaria in the study area, focused control actions of An. coluzzii, a key vector that transmits malaria parasites, should be directed outdoors before the month of June.