Novel enteric viruses in fatal enteritis of grey squirrels

Astro- and kobuviruses infect both humans and animals. Here, we report on the disease history, detection and genomic characterization of novel astro- and kobuviruses from fatal diarrhoea of two juvenile grey squirrels. The virus particles had enterovirus-like morphology and a diameter of 28-32 nm. Next-generation sequencing confirmed astro- and kobuviruses and sequence analysis revealed typical astrovirus and picornavirus genome organizations. The astrovirus ORF2 sequence clustered with a clade of unassigned astroviruses, with marmot and rodent mamastroviruses as closest relatives. For the kobuvirus, divergences greater than 49.4 % for P1 and 43.5 % in the non-structural proteins indicated a novel species. However, phylogenetic analysis of the 3D polymerase showed that it clustered with that of the newly classified ludopivirus A1, suggesting a previous recombination event in the evolution of the kobuvirus. Our data provide further insights into the diversity of astro- and kobuviruses and broaden the spectrum of viruses infecting grey squirrels.