Novel murine norovirus-like genes in wild rodents in Japan.

Novel murine norovirus (MNV)-like sequences were detected in 7 (14.9%) of 47 fecal and intestinal samples obtained from wild rodents in Japan. Sequencing and genetic analyses of the 7 MNV-like genes, 6 derived from Apodemus speciosus and 1 from Rattus rattus, suggested that these sequences form a cluster distinct from known MNV within genogroup V and differed even among clusters of wild rodents. Considering these results, MNV might be genetically diverse depending on the host species or distribution. This is the first report suggesting the prevalence of MNV in A. speciosus and R. rattus.