Discovery of rosavirus 2, a novel variant of a rodent-associated picornavirus, in children from The Gambia

We describe the identification of a novel picornavirus recovered from the fecal specimen of a child in The Gambia, provisionally named rosavirus 2. Comparison of the rosavirus 2 complete genome demonstrated 71.9% nucleotide identity to its closest relative rosavirus M-7, an unclassified picornavirus identified from rodent fecal material. A unique RNA structure was predicted in the 3' UTR of rosavirus 2 that was conserved with rosavirus M-7 and cadiciviruses. We detected rosavirus 2 in four pediatric fecal specimens (0.55% prevalence) in a Gambian diarrheal case-control cohort, but we did not detect it in a panel of 634 pediatric diarrheal stool specimens from the USA. There was no statistical evidence that rosavirus 2 was associated with diarrheal cases. This study broadens our understanding of unknown viruses present in children in developing country settings.