abstract:Muromegalovirus is a genus of viruses found in rodents that belong to the betaherpesviridae subfamily of herpesviruses. Murid viruses murid herpesvirus 1 (MuHV-1) and murid herpesvirus 2 (MuHV-2)--previously defined as mouse cytomegalovirus (MCMV) and rat cytomegalovirus (RCMV)--belong to this genus.