Hefer valley virus: a novel ephemerovirus detected in the blood of a cow with severe clinical signs in Israel in 2022

A novel ephemerovirus was identified in a Holstein-Friesian cow in the Hefer Valley, Israel, that showed severe and fatal clinical signs resembling an arboviral infection. A sample taken during the acute phase tested negative for important endemic arboviral infectious cattle diseases. However, sequencing from blood revealed the full genome sequence of Hefer Valley virus, which is likely to represent a new species within the genus Ephemerovirus, family Rhabdoviridae. Archived samples from cattle with comparable clinical signs collected in Israel in 2021 and 2022 tested negative for the novel virus, and therefore, the actual distribution of the virus is unknown. As this is a recently identified new viral infection, the viral vector and the prevalence of the virus in the cattle population are still unknown but will be the subject of future investigations.