Last reviewed 06/2021

Cytomegalovirus refers to any of a group of highly host-specific herpesviruses, infecting Man, monkeys or rodents, producing unique large cells with intranuclear inclusions ('Owls eyes'). The virus specific for man causes cytomegalic inclusion disease, and it has been associated with a syndrome resembling infectious mononucleosis.

The virus is widespread in the community. About 50% of pregnant women in the UK have antibodies to CMV. Cytomegalovirus infection in utero can cause significant clinical problems. These may present in the perinatal period, or, due to the latent nature of the virus, at a time when the immune system is compromised.

Other than vertical transmission, passage of CMV between children and from children to adults is common, whereas adult-to-adult transmission is rare.