Mapping the Potential Risk of Coronavirus Spillovers in a Global Hotspot

Abstract

Bats harbor approximately a third of known mammal viruses, including the recent coronaviruses SARS-CoV-1 and SARS-CoV-2 that likely spilled over in Asia. As spillover risk increases due to habitat loss and fragmentation, we identified potential zoonotic spillover and pandemic risk hotspots by combining landscape characteristics with the diversity of competent hosts, with horseshoe bats (genus Rhinolophus) used as proxies for zoonotic pathogen reservoir hosts. We estimated the risk of coronavirus emergence in South and Southeast Asia by integrating Rhinolophid species distributions, forest fragmentation, and human population density data. Two scenarios were considered: one using baseline forest cover data, and another incorporating new regional infrastructure which drives further fragmentation. Results showed that under both scenarios, spillover risk hotspots are concentrated in Indochina and southern China, where host species richness and fragmentation are high, and where coronaviruses were previously detected in bat populations. Simulation of pandemic spread from the spillover risk hotspots using network models revealed risk hotspots clustered in Bangladesh and northeast India. These results highlight the vulnerability of human population centers and heightened risks from habitat fragmentation in Asia, especially given its history of recent coronavirus spillovers that became pandemics. Identifying hotspots emphasizes the need for a multidisciplinary approach to protect ecosystem integrity for public health, paving the way for improved predictive capabilities and targeted disease surveillance in at-risk regions.