Distinct spread of DNA and RNA viruses among mammals amid prominent role of domestic species
Emerging infectious diseases arising from pathogen spillover from mammals to humans comprise a substantial health threat. Tracing virus origin and predicting the most likely host species for future spillover events are major objectives in One Health disciplines. However, the species that share pathogens most widely with other mammals, and the role of different wildlife groups in sharing viruses with humans remain poorly identified. To address this challenge, we applied network analysis and Bayesian hierarchical models to a global database of mammal-virus associations. We show that domesticated mammals and some primates hold the most central positions in networks of known mammal-virus associations. We revealed strong evidence that DNA viruses were phylogenetically more host specific than RNA viruses, while the frequencies of sharing viruses among hosts and the proportion of zoonotic viruses in hosts were larger for RNA than DNA viruses. Among entire host-virus networks, Carnivora and Chiroptera hold central positions for mainly sharing RNA viruses with other host species, while network centrality of Primates scored relatively high for sharing DNA viruses. Ungulates hold central positions for sharing both RNA and DNA viruses. Acknowledging the role of domestic species in addition to host and virus traits in patterns of virus sharing is necessary to improve our understanding of virus spread and spillover in times of global change.