Natural Infections of Wild Creek Chubs and Cultured Fathead Minnow by Chinese Grass Carp Reovirus (Golden Shiner Virus)

Wild creek chubs Semotilus atromaculatus and farmed fathead minnow Pimephales promelas were cultured for viruses on epithelioma papulosum cyprini and fathead minnow cells. A syncytia‐forming virus was isolated from creek chubs and both healthy and moribund fathead minnow with skin and visceral lesions. The isolates were positive by a reverse‐transcriptase−polymerase chain reaction assay that amplifies segments 1 and 2 of Chinese grass carp reovirus (CGRV; also known as golden shiner virus and grass carp hemorrhagic virus). Sequencing of the amplicons showed that the isolates were 93–99% identical to each other and to North American CGRV isolates from grass carp Ctenopharyngodon idella and golden shiners Notemigonus crysoleucas and 87–93% identical to grass carp isolates from China. Homologies to other fish reoviruses were only 3–42%.