Suitability of anthrax (Bacillus anthracis) in the Black Sea basin through the scope of distribution modelling

The Black Sea basin has a strategic geographic location bridging Asia and Europe and depends on traditional livestock practices for their local economies. Anthrax, a zoonotic bacterial disease caused by Bacillus anthracis, poses a significant global threat impacting public health, food security, pastoralist communities, and national economies. The disease is endemic or sporadic in the Black Sea basin, however, the study of its distribution has seldom been addressed, despite its burden and the presence of historical B. anthracis burial sites in the region. The viability of B. anthracis in a particular region is going to be influenced by multiple environmental factors, such as soil composition, climate, vegetation, and host abundance. For characterizing the potential distribution of B. anthracis in the Black Sea basin and assessing the potential for anthrax outbreaks, we applied an ecological niche modelling framework using the Maxent algorithm. This machine-learning algorithm models species distributions based on presence data and background information from a specified calibration region. We analyzed multiple variable combinations and proposed a novel approach for interpreting in-risk anthrax areas. Our findings underscored the importance of host abundance to the anthrax dynamics in the region. We identified anthrax-suitable areas spanning central and eastern Türkiye, Armenia, southern Georgia, southern Russia, Bulgaria, southern and eastern Romania, Hungary, Moldova, and southern Ukraine, which align with findings from previous global and regional studies on the potential suitability of anthrax. The insights gained from our research may help to develop targeted interventions, such as awareness and educational campaigns about anthrax, supervision of anthrax-infected carcasses disposal, and the promotion of livestock vaccination in high-risk areas. Additionally, these results can inform policies to mitigate the spread of anthrax in pastoralist communities in the Black Sea basin and foster collaboration between veterinary and public health entities on anthrax control.