Global Patterns and Future Changes in West Nile Virus Risk Under Climate Change

Over the past two decades, West Nile virus (WNV) has spread to many countries and caused substantial losses to life and property worldwide, while climate change has further influenced its transmission by affecting its vectors. To understand the global distribution of WNV and changes in its risk, 2039 occurrence records were collected and a MaxEnt model was used to simulate the current and future potential risk distribution. Temperature seasonality, annual mean temperature, precipitation of the coldest quarter, and precipitation seasonality contributed relatively strongly to the spatial distribution simulation of WNV, together accounting for 83.3%. Overall high-risk areas showed a certain banded pattern, mainly concentrated between 25 °N and 55 °N in the Northern Hemisphere and between 25 °S and 35 °S in the Southern Hemisphere. Under global climate change, the area classified as high potential risk by the MaxEnt model is projected to expand. In the 2050s and 2070s, the average area classified as high potential risk is projected to increase by 0.133 × 106 km2 and 0.106 × 106 km2, respectively, representing increases of 7.705% and 6.161%. The best prevention strategy is mosquito control, especially in areas at high risk for WNV. These results may help identify areas where enhanced WNV surveillance and vector control warrant further consideration under climate change.