Spatiotemporal dynamics of Rattus tanezumi density and its implications for rodent-borne diseases in the Three Gorges Reservoir Area, China

Rattus tanezumi ( R. tanezumi ), a major vector for plague, leptospirosis, and hantavirus, exhibits population dynamics in the Three Gorges Reservoir (TGR) Area of China that are influenced by climate and reservoir-induced environmental changes, thereby impacting disease transmission risks. This study investigated the spatiotemporal dynamics of R. tanezumi and its association with key meteorological and environmental factors from 2015 to 2021. Using Geographic Information Systems (GIS) for spatiotemporal analysis and a Generalized Additive Model (GAM), we identified the current month's average temperature and relative humidity, together with three-month-lagged precipitation and the Normalized Difference Vegetation Index (NDVI), as significant drivers. The relationship was modeled (Yi,t = α + s ₁ (M0Avg_Temp) + s ₂ (M0Avg_RHU) + s ₃ (M3Precip) + s ₄ (M3NDVI) + ε; R²= 0.12, Deviance explained = 14%, GCV = 0.4438), revealing an optimal proliferation temperature around 20°C. Density showed negative correlations with both current relative humidity and lagged precipitation, and a fluctuating decline with increasing lagged NDVI. As the first investigation of its kind, this study demonstrates how climatic and environmental factors shape the spatiotemporal distribution of R. tanezumi in the TGR Area, providing critical insights for predicting outbreaks and formulating targeted surveillance and control strategies against rodent-borne diseases in this vulnerable region.