Assessment of Vector Breeding Habitats Created by Poor Drainage in Enugu Urban Areas

This study assesses the mosquito vector breeding habitats created by poor urban drainage conditions in Enugu, Enugu State, South East Nigeria, examining the relationship between drainage infrastructure quality, standing water accumulation, and larval density of Anopheles and Aedes mosquitoes as vectors of malaria and dengue fever respectively. Urban malaria incidence in Nigerian cities is increasing alongside rapid urbanisation, and poor drainage infrastructure is a key determinant of breeding site availability. A field survey was conducted across twelve urban wards in Enugu North and South Local Government Areas to inventory drainage conditions and characterise standing water bodies by type, area, and larval density. Larval sampling used standard dipping methods, and species identification was performed on preserved specimens. Drainage infrastructure condition was assessed using a structured scoring protocol. Results show that blocked tertiary drains containing stagnant water are the most numerically abundant breeding habitat type, accounting for 61 percent of positive Anopheles breeding sites. Discarded containers including tyres, buckets, and cans are the dominant Aedes breeding habitats, particularly in peri-market areas. Larval density is significantly higher in wards with drain blockage scores in the highest severity category. A spatial analysis identifies six high-density breeding habitat zones concentrated in low-lying areas with the poorest drainage infrastructure. Anopheles larvae are found in all twelve wards, while Aedes breeding is more concentrated in market and commercial zones. Recommendations include targeted drain desilting and a community clean-up programme for container habitats. Keywords: vector breeding, drainage, mosquito larvae, malaria, Enugu.