21Avr 25
As part of our work to develop new genetic approaches for malaria control, the University of California Malaria Initiative (UCMI) is studying mosquito movement and breeding patterns in São Tomé and Príncipe. In a study published last year, we investigated the dispersal dynamics of Anopheles coluzzii – the only malaria vector on this island nation. Our recent study examines how environmental factors influence A. coluzzii breeding sites and shape mosquito dispersal across São Tomé and Príncipe.
UCMI’s team collecting mosquito larvae in São Tomé and Príncipe. Photograph: UCMI
Understanding movement and interactions between mosquito populations is key to designing malaria control strategies. The data collected will also offer key insights that will guide the design of potential field evaluations of the technology we are working to develop.
To determine the most suitable habitats for A. coluzzii, we used computer modeling to analyze environmental conditions such as temperature, elevation, and human population density. Our results show that the northeastern regions of both São Tomé and Príncipe islands provide the most suitable conditions for A. coluzzii larval development, with lower elevations and higher human population densities likely contributing to greater habitat availability. Interestingly, our climate modeling suggests that the mosquito’s geographic distribution on the islands will remain largely unchanged under current climate projections, even without additional interventions.
Lisa Chamberland, Postdoctoral Researcher, UCMI, University of California, Davis, carrying out adult mosquito collections in São Tomé and Príncipe. Photograph: UCMI
We also examined how mosquitoes move between different areas and identified potential environmental factors influencing their dispersal. Our analysis of whether certain variables could promote or restrict gene flow — the transfer of genetic information between populations — showed that roads may play a role in facilitating mosquito movement. This could potentially be due to the presence of resting spots and water-filled breeding areas along roads. Additionally, our research suggests that higher elevations may limit A. coluzzii movement, leading to more isolated mosquito groups.
Although progress has been made in reducing malaria incidence in São Tomé and Príncipe over the past two decades, sustaining these achievements will require stepping up efforts to control the disease. By mapping where A. coluzzii mosquitoes breed and how they move, we aim to provide critical data that could support the development of new genetic tools to fight malaria in São Tomé and Príncipe and beyond.
Read the full study here.
