Predicted spatial distribution of the primary Lassa virus reservoir, the multimammate mouse, in Africa

This study predicts the potential spatial distribution of the multimammate mouse (Mastomys natalensis), the primary host of Lassa virus, a major public health concern across West Africa.

Correlative maximum entropy models were constructed with occurrence records of M. natalensis from Global Biodiversity Information Facility, using long-term bioclimatic variables at ~1 km resolution as predictors. Candidate models were evaluated and best models were selected based on statistical significance, predictive ability, and model fitting and complexity. Models were projected to the African continent.

Median predictions from the best-supported models indicated extensive areas of moderate to high suitability across sub-Saharan Africa, with suitability concentrated within the tropical and subtropical belts of West, Central, and East Africa. Suitability declined sharply across arid regions, particularly the Sahara and parts of the Horn of Africa. Within Nigeria, a focal area of the study, the predicted suitability was broadly high across southern and central regions, with a gradual decline toward Sahel-adjacent northern areas. Sub-national projections for Lagos, Oyo, Edo, Kano, and the Federal Capital Territory revealed spatial heterogeneity in suitability, consistent with underlying climatic gradients in temperature and precipitation that shape habitat conditions for M. natalensis.

These findings provide a spatial framework for prioritizing rodent surveillance and supporting targeted Lassa fever preparedness and control strategies.