Introduction In light of climate change, proliferation of mosquito-borne diseases like dengue and malaria is a mounting concern, driven by expanding mosquito populations as a result of favorable environment for their survival. Addressing public health challenges caused by mosquitoes demands constant innovation and sustainable solutions. Objective This study responds to recent reports of Wolbachia infections in West African mosquito species, suggesting their potential as biocontrol agents for disease vectors. We seek to detect the presence of Wolbachia pipientis in different mosquito species in Ota and identify mosquito species present in the area. Method We conducted a comprehensive mosquito larval surveillance in Ota, Ogun State, Nigeria using a systematic stratified random sampling method from November 2022 to March 2023 to assess mosquito species distribution and Wolbachia infection. During this period, we surveyed mosquito larvae in various sites, rearing them to adulthood. We meticulously identified species, sex, and collection locations then, stored specimens at − 20 °C. Sodium chloride precipitation protocol was employed to extract DNA from the mosquitoes individually. Polymerase chain reaction (PCR) analysis was carried out using one to one point five microliter of DNA, with distilled water as negative control. Results Out of 1265 emerging young adult mosquitoes, 62.1% were females, while 37.1% were males. Aedes species constituted 22.2%, Anopheles 37.2%, and Culex 40.6% of the population. DNA analysis identified Wolbachia infection in Ae. albopictus and Ae. aegypti, with wsp gene sizes ranging from 590 to 632 bp, confirming Wolbachia presence by sequencing. Conclusion Our study is the first report on Wolbachia presence in Aedes sp within this region, which suggests that this mosquito species is a less likely vector for dengue virus and other related infectious agents. The study highlights the importance of continuous mosquito population and breeding site monitoring for potential biocontrol interventions against disease vectors.

Pyrethroids account 89.9% of all vector control insecticide use in African in terms of normal spray coverage This study aims to identify mosquito breeding sites and assess the knockdown resistance (kdr) gene responsible for pyrethroids resistance of Anopheles populations in Ota. Anopheles larvae collected from the Atan and Nestle (6⁰ 40' N, 3⁰ 09' E & 6⁰ 41’N, 3⁰ 9’E) were grown to adulthood in an insectary. Female mosquitoes (2-5days old) not blood-fed were evaluated for sensitivity to 0.05% deltamethrin using the standard method of the World Health Organization. To distinguish the An. gambiae complex related species, rDNA intergenic spacers were amplified using PCR. The kdr- genes were genotyped in Anopheles gambiae females. 438 female mosquitos were gathered in total; Aedes (11.17%), Anopheles (28.8%) and Culex (50.9%) being the most abundant species specimens collected. WHO bioassay for exposure to deltamethrin mortality rate for Anopheles species was 39% (Atan) and 37% (Nestle) respectively. Anopheles mosquitoes were resistant to deltamethrin. Anopheles gambiae was found as the main vector within Ota. The Probit model was utilised to obtain the median knockdown time; KDT₅₀ and KDT₉₅ for both sites (Nestle; KDT₅₀ = 45.829 Min, KDT ₉₅ = 88.854 Min & Atan; KDT ₅₀= 44.957 Min, KDT₉₅ = 93.473 Min). The total frequency of the kdr allele (i.e., kdr-W) resistant individuals was 0.86 in Atan and 0.796 in Nestle site. This data, despite being preliminary, highlights the importance of monitoring An. gambiae numbers in these areas to develop an effective approach for managing pyrethroid and DDT resistance in mosquito control. Susceptibility to pyrethroids can be partially restored when used alongside synergist (e.g Piperonyl butoxide- PBO) suggesting likely involvement of metabolic resistance.

Malaria continues to be a significant health challenge worldwide, causing 282 million cases and 610,000 deaths in 2024, especially in sub-Saharan