Integrating MaxEnt and copula models to assess plague-associated ecological suitability under climate change in Northern Tianshan, China

BACKGROUND: Plague, a paradigmatic zoonotic disease, depends on the intricate interplay among ecological environments, climatic conditions, and host-vector-pathogen interactions for its transmission. Climate change is reshaping the ecological distribution and transmission risks of plague. However, a systematic understanding of the future epidemiological trends for the Northern Tianshan Natural Plague Focus in Xinjiang remains limited. METHODS: By employing an optimized maximum entropy model (MaxEnt) integrated with joint distribution Copula functions, the spatiotemporal dynamics of Marmota baibacina, Yersinia pestis, and plague transmission risk under both current and future climate change scenarios were evaluated. RESULTS: The results revealed that the high-suitability habitats for both M. baibacina and Y. pestis within the focus were projected to exhibit trends of contraction and expansion in the future. These patterns could be attributed to the distinct environmental factors shaping their distributions. Specifically, the distribution of M. baibacina was primarily determined by temperature (Bio6 and Bio7) and precipitation (Bio15), whereas the distribution of Y. pestis was predominantly influenced by Bio15 and elevation. The spatial distribution of high-risk areas for plague transmission was projected to undergo dynamic changes, characterized by phases of stability, contraction, and expansion. Furthermore, the centroid of these high-risk regions may shift from Wusu City to Nileke County. CONCLUSIONS: Under future climate scenarios, the distribution and transmission risk of plague in the focus may be influenced by environmental factors, resulting in scenario- and period-dependent spatial changes. The western region of the focus is anticipated to experience the most pronounced shifts and is projected to remain at elevated risk of epizootic plague.