This study investigates the contribution of climate change to the spatial expansion of West Nile virus (WNV) in Europe, a mosquito-borne pathogen that poses a significant public health threat. By using ecological niche models, the researchers assess the risk of local WNV circulation and compare factual simulations with counterfactual scenarios where long-term climate trends have been removed. The findings indicate a notable increase in the area ecologically suitable for WNV circulation from 1901 to 2019, which remains largely unchanged in the counterfactual scenario. The study highlights that while historical changes in population density have contributed to the increased risk of exposure, climate change has been a critical driver of the heightened risk of WNV circulation in Europe. The results suggest that climate change is directly involved in the establishment of WNV hotspots in southeastern Europe, emphasizing the need for further research on the evolution of infectious disease distributions under different climate change scenarios to inform public health strategies.This study investigates the contribution of climate change to the spatial expansion of West Nile virus (WNV) in Europe, a mosquito-borne pathogen that poses a significant public health threat. By using ecological niche models, the researchers assess the risk of local WNV circulation and compare factual simulations with counterfactual scenarios where long-term climate trends have been removed. The findings indicate a notable increase in the area ecologically suitable for WNV circulation from 1901 to 2019, which remains largely unchanged in the counterfactual scenario. The study highlights that while historical changes in population density have contributed to the increased risk of exposure, climate change has been a critical driver of the heightened risk of WNV circulation in Europe. The results suggest that climate change is directly involved in the establishment of WNV hotspots in southeastern Europe, emphasizing the need for further research on the evolution of infectious disease distributions under different climate change scenarios to inform public health strategies.