Pangolin-Associated Viruses: Diversity, Evolutionary Adaptation, and Zoonotic Spillover Risks

Pangolin-associated viruses have received considerable attention because of their diversity and potential zoonotic relevance, yet the evidence remains fragmented. This review evaluates the diversity, evolutionary adaptation, and zoonotic spillover risks of pangolin-associated viruses. Diverse RNA and DNA viruses, such as coronaviruses, paramyxoviruses, astroviruses, parvoviruses, and papillomaviruses, have been detected in pangolins, showing substantial taxonomic and genomic variation. Studies of selected pangolin-associated viral groups have documented sequence variation and identified signals of recombination or reassortment. Some pangolin coronaviruses can use human receptors and replicate in human-derived cells, organoids, or transgenic animal models. Several viruses known to infect humans have also been detected in pangolin samples, although conclusive evidence of natural spillover from pangolins to humans is lacking. Most studies examine Sunda and Chinese pangolins from illegal trade or rescue centers, relying largely on nucleic acid detection and sequence analysis. Habitat disruption, wildlife trafficking, long-distance transport and captive-rescue operations may increase cross-host-pathogen exposure. Future work should prioritize surveillance of wild pangolin populations of known provenance and integrate virus isolation, tissue localization, serology, and functional assays to support pangolin conservation and reliable zoonotic-risk evaluation.