Human betaherpesvirus 5, sometimes called human cytomegalovirus (HCMV),[citation needed] is the type species of the virus genus Cytomegalovirus, which in turn is a member of the viral family known as Herpesviridae or herpesviruses. It is also commonly called CMV.[2] Within Herpesviridae, HCMV belongs to the Betaherpesvirinae subfamily, which also includes cytomegaloviruses from other mammals.[3]