Identification of a novel norovirus species in fox.

A novel Norovirus (NoV) was identified by viral metagenomic analysis in fox fecal samples from the Xinjiang Uygur Autonomous Region of China. The virus exhibited typical genomic characteristics of NoVs. It was closely related to the canine NoV GVII strains with 86.0-86.2% and 91.9% amino acid identities in the capsid protein VP1 and RNA-dependent RNA polymerase (RdRp), respectively. The fox NoV clustered phylogenetically with the two canine NoV GVII strains, and it was distant from other NoVs. According to the new classification criteria of NoVs, the new fox NoV belongs to the same genotype as GVII, similar to canine GVII NoVs. Moreover, key amino acid residues in the Histo-blood group antigen (HBGA) binding sites and the HBGA binding pattern of the fox NoV differed significantly from those of human and canine GVII NoVs. This study identified a new GVII norovirus from wild foxes in China. These findings enrich our understanding of the diversity of NoVs and provide further evidence regarding the genetic heterogeneity of NoVs in carnivores.