Urban malaria vector dynamics in Accra, Ghana.

Area of Science:

• Public Health Entomology
• Urban Tropical Disease Ecology

Background:

• Urban malaria presents an increasing challenge in sub-Saharan Africa due to rapid urbanization and vector adaptation.
• Limited data exists on the diversity and malaria transmission potential of urban mosquito vectors.

Purpose of the Study:

• To assess the abundance, species composition, and behavior of Anopheles gambiae sensu lato (s.l.) in Accra, Ghana.
• To identify high-risk areas for malaria transmission within diverse urban socioeconomic settings.

Main Methods:

• Mosquitoes were collected across fifteen sites in Accra during dry and rainy seasons (2022-2024).
• Host-seeking and resting Anopheles mosquitoes were sampled to determine abundance and species.
• Data was analyzed across different socioeconomic settings and land-use types (irrigation, peri-urban).

Main Results:

• A total of 20,945 host-seeking and 1,613 resting Anopheles mosquitoes were collected.
• Anopheles mosquito abundance was highest in irrigation and peri-urban sites, and lowest in low socioeconomic areas.
• Anopheles gambiae sensu stricto (s.s.) dominated host-seeking populations, while Anopheles coluzzii dominated resting populations.

Conclusions:

• Irrigation and peri-urban areas in Accra are identified as significant hotspots for Anopheles mosquitoes.
• Targeted surveillance and control strategies are crucial for these identified hotspots to mitigate urban malaria risk.