cmV

Cytomegalovirus (CMV) is a double-stranded DNA virus in the herpesvirus family, specifically human herpesvirus 5, a member of the betaherpesvirinae subfamily. CMV infections are common worldwide and usually asymptomatic in healthy people. After primary infection, the virus establishes lifelong latency with periodic reactivation.

CMV is transmitted through contact with infected body fluids, including saliva, urine, blood, breast milk, sexual contact, and organ or blood transfusions. Congenital CMV occurs when a pregnant person transmits the virus to the fetus, either at primary infection or reactivation. Seroprevalence varies by region and age; most infections are acquired during childhood.

Clinical presentation varies. In immunocompetent adults, CMV infection is often mild or silent. In immunocompromised patients, CMV can cause retinitis, esophagitis or colitis, pneumonitis, hepatitis, and systemic disease. Congenital CMV can cause hearing loss, microcephaly, periventricular calcifications, seizures, jaundice, hepatosplenomegaly, anemia, and growth restriction; many infants are asymptomatic at birth but develop sequelae later.

Diagnosis relies on detection of CMV DNA by PCR in blood, urine, or saliva, viral culture, or antigenemia assays in certain settings. Serology can support diagnosis but is not sufficient alone to establish perinatal infection. In newborns, CMV testing of urine or saliva within the first two to three weeks of life is commonly used.

Treatment includes antiviral medications such as ganciclovir or valganciclovir, particularly for congenital CMV and for CMV disease in immunocompromised patients. Alternatives include foscarnet or cidofovir in specific cases. Prevention centers on standard hygiene and infection control; there is currently no licensed CMV vaccine, though several candidates are under development.

CMV is a major cause of congenital infection and a leading cause of non-genetic sensorineural hearing loss in children. Public health strategies emphasize surveillance, early detection, and management, with ongoing research into vaccines and improved therapies.