Cytomegalovirus Fact Sheet

Cytomegalovirus (CMV) infection is caused by a virus

CMV is a virus that is harmless to most people. CMV is a member of the herpes group of viruses.

Most people get CMV at some time in their lives

Most adults and children who catch CMV have no symptoms and are not harmed by the virus. Symptoms some people may get are fever, sore throat, fatigue, and swollen glands. CMV can stay in the body (latent form) and can reactivate in some people.

CMV is usually spread through close person-to-person contact

CMV may be found in body secretions, such as urine, saliva, feces, blood and blood products, breast milk, semen and cervical secretions. CMV can be in these secretions for months to years after the infection. Infection is spread from person to person through close contact, including kissing as well as getting saliva or urine on your hands and then touching your nose or mouth. A pregnant woman who is infected may also pass the virus to her developing baby. A baby may also be infected during birth, as a newborn, and through breast feeding. CMV can be spread through blood transfusion and organ transplantation.

Two groups of people are at higher risk of problems from CMV:

Unborn children of women who get CMV for the first time or have a reactivation of infection during pregnancy. About 7 to 10% of these babies will have symptoms at birth or will develop disabilities including mental retardation, small head size, hearing loss, and delays in development.
People with certain illnesses or on certain medicines that weaken the immune system (for example, persons with HIV, or persons taking chemotherapy or organ transplant medicines). If infected, these people may get a more serious illness.

Laboratory tests can look for the virus or for antibodies to the virus

These tests can be ordered to diagnose CMV in a person with symptoms. Antibody levels can be tested to see if the person was infected with CMV in the past.

Exclusion of children with CMV is not necessary

Children known to have CMV should not be excluded from school or child care facilities. This is because CMV is very common and there are many other healthy children who may have the virus too—so, good personal hygiene is needed—all the time.

Prevent infection with good personal hygiene

CMV is widespread in the community. The best way to prevent or lessen the chance of infection is through good hygiene. Always wash your hands after diapering and handling any baby at home or at work since urine and saliva are important sources of CMV.

Pregnant women should check with their doctors

Pregnant women and women considering pregnancy should realize that they may be at risk of CMV from contact with saliva or urine of family members, others in the community, and in occupational settings. A pregnant woman or a woman who is considering pregnancy should talk to her doctor if she cares for infants or young children, or handles urine or saliva in any home or occupational setting. The doctor may want to check her blood to see if she has been exposed to CMV. Pregnant women do not necessarily need to be excluded from such situations, but should know about the possible risks at home and at work and that good personal hygiene is the most important preventive measure. In situations of good hygiene, even a woman who has never had CMV infection is at very low risk of catching CMV.