Spatial Distribution and Ecological Niche Modelling of Anopheles Funestus, a Key Malaria Vector in Malawi

Abstract Malaria remains a major public health concern in African societies, yet the environmental, hydrological, and ecological factors driving the distribution of Anopheles funestus in pro-poor countries such as Malawi remain understudied. Our study utilised ecological niche modelling to assess the current drivers shaping An. funestus distribution in Malawi using a MaxEnt model, by integrating multiple factors: climate, hydrology, biophysical, and water resources data derived from the WorldClim database and EarthData. Occurrence data were collected from the Malaria Alert Centre at Kamuzu University of Health Sciences. We used 8,650 mosquito occurrence records and environmental raster files resampled at 30 m resolution to build our predictive model. The results show that Land Use Land Cover was the major predictor variable, scoring 48.7%, followed by annual mean temperature range (Bio_7) at 17.5%, and precipitation of the wettest quarter. The model achieved strong predictive performance (AUC = 0.914). Among the biophysical drivers, the Biodiversity Intactness Index was a notable vegetation-related variable; although it had a low percent contribution, its low permutation importance suggests it has better predictive power than NDVI. The results also show an increase in habitat suitability in the eastern region of Malawi, where mean habitat suitability increased by 1.45, and lower suitability in the northern region. The findings suggest that not only climate, as other researchers have emphasised, but a multitude of factors are responsible for shaping An. funestus distribution.