Natural Infections with Human Respiratory Syncytial Viruses in Non-Primate Animals, Pangolins

Respiratory syncytial virus (RSV) is the leading cause of severe respiratory disease in children under 2 years of age, and responsible for substantial disease burden in infants and elder people in either developed or developing countries 1,2 . RSV has only been circulating among humans, though it was first isolated from chimpanzees 3 . Here we report natural infections of RSVs (40%) in Malayan pangolins ( Manis javanica ) with high identity (99.3-99.8%) to human strains by comparing entire genomes. Phylogenetic analyses revealed that five pangolin RSVs belonged to RSV-A ON1 and seven to RSV-B BA genotypes, which are currently prevalent in humans. Three substitutions existed in pangolin RSV-B fusion protein subunit, which involves binding of viral glycoprotein with the receptor. We firstly identified natural infections of human RSVs in non-primate animals, and implied that people should kept away from pangolins to prevent mutual transmission of pathogens between humans and the animals.