Climate Change and Socioeconomic Vulnerability: The Carpathian Basin as a Potential Hotspot in the Dissemination of Dirofilaria repens in Europe.

Dirofilaria repens is a zoonotic parasite expanding across Europe due to climate change. We hypothesised that in this process, the Carpathian Basin has a facilitating effect. Using 426 georeferenced European cases, the probability of infection occurrence was determined in relation to climatic factors, surface water availability, regional social deprivation, and stray dog population density. To analyse the potential impacts of ecological and social factors (deprivation and stray dog population density), the MaxEnt algorithm, and spatial Empirical Bayes smoothing and bivariate local indicators of spatial association (BiLISA) index calculation were employed, respectively. MaxEnt analysis revealed that the mean warmest month temperature (MWMT; 22.8-25.1°C), winter mean minimum temperature (>-2.1°C), and summer precipitation (28.6-231 mm) have the strongest impact on the probability of the parasite's occurrence in Europe. Social factors have significance in the eastern Balkans and the Carpathian Basin, but not in Western Europe. The Carpathian Basin appears to be a hotspot, similar to Mediterranean coastal areas. Furthermore, the Danube Valley acts as an ecological corridor for subtropical vector-borne parasites. Our findings confirm that summer warmth is the primary ecological driver of the parasite's range expansion, which is facilitated by the Carpathian Basin due to climatic and socioeconomic conditions.