Vector Competence Assessment and Seasonal Transmission Potential of Aedes aegypti for Dengue Virus in Onitsha, Anambra State, South East Nigeria

Dengue fever is an emerging vector-borne disease in Nigeria, with seroprevalence studies increasingly documenting transmission in urban settings. Onitsha, the commercial capital of Anambra State, is one of Nigeria's most densely populated trading cities, and its environmental conditions favor the proliferation of Aedes aegypti, the primary dengue vector. This study assesses the vector competence of Onitsha Aedes aegypti populations for dengue virus and estimates the seasonal vectorial capacity over a twelve-month surveillance period. Field-collected Ae. aegypti larvae will be reared and adult females used in oral infection experiments with dengue serotypes 1, 2, and 3. Infection, dissemination, and transmission rates will be measured at 7 and 14 days post-infection using RT-PCR. Seasonal vectorial capacity will be modeled using entomological parameters, namely biting rate, longevity, and population density, collected from field surveillance. This study contributes critical missing data on dengue transmission risk in South East Nigeria, where health systems are currently unprepared for dengue case management. Results will be submitted to the Nigeria Centre for Disease Control and the Anambra State Ministry of Health to inform dengue surveillance protocol development. Keywords: Aedes aegypti, dengue virus, vector competence, Onitsha, transmission potential