Inherent Virus Characteristics and Host Range Drive the Zoonotic and Emerging Potential of Viruses

Abstract

Background: Understanding the zoonotic and emerging potential of viruses is important to inform disease control and prevention programs. We demonstrate that inherent virus characteristics and virus host-range allow prediction of the zoonotic and disease emergence potential of virus species. Methods: We examined recent International Committee on Taxonomy of Viruses (ICTV) virus species (n=4958) data to identify 1479 vertebrate virus species and their host range. Species and host range were then used as key predictors of two host-associated outcomes - zoonotic potential (confirmed and potential) and disease emergence. Findings: We categorised 2010 viruses as Animalia viruses, including 1479 vertebrate infecting viruses. Vertebrate viruses were further categorised as human (n=404), bat (n=219), rodent (n=186), non-human primate (n=206) and livestock (n=267). In addition to 164 known zoonotic viruses (zoonoses confirmed), we report 231 viruses that infect humans and have also been reported from other vertebrate hosts (zoonotic potential). Our model predicted 27 viruses - not reported as zoonotic to date - to have zoonotic potential. Some of these viruses (n=11, 40·7%) have already been isolated from humans and other vertebrate host(s). Most of the predicted zoonotic (confirmed) risk viruses belonged to the virus families Peribunyaviridae (n=4) and Flaviviridae (n=9). Viruses with highest predicted probabilities included Thiafora orthonairovirus (p=0·92) and Uukuniemi phlebovirus (p=0·91). We identified 12 viruses - not reported as emerging human viruses to date - with an emergence risk. Most of these viruses belonged to the families Arenaviridae (n=3) and Flaviviridae (n=5). Viruses with the highest predicted probabilities included mucambo virus (p=0·88) and lymphocytic choriomeningitis mammarenavirus (p=0·67). We report significant interactions in the host range as well as host-viral traits, not previously reported, that influence the zoonotic and emergence potential of viruses. Interpretation: We conclude that inherent virus characteristics are important to identify their zoonotic and emerging potential. RNA viruses reported from non-human primates, livestock viruses not reported from invertebrates and bat viruses neither reported from invertebrates nor from birds were more likely to be zoonotic. Zoonotic pathogens also reported from non-human primates were more likely to emerge. We recommend the influential role of phylogenetic relatedness and social closeness amongst humans and other vertebrates to be interpreted given the significant interactions that occur in host-range as well as host-viral traits that influence the zoonotic potential of a virus. Funding: Department of Education and Training, Australian Government. Declaration of Interest: We declare no competing interests. Ethical Approval: Not required.