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Cytomegalovirus Infection


Cytomegalovirus (CMV) is a type of herpes virus that often causes asymptomatic infection in otherwise healthy persons.


There are three recognizable clinical syndromes:

1. CMV inclusion disease of the newborn. Cytomegalic inclusion disease of the neonatal (newborn) period is characterized by variable severity ranging from an asymptomatic infection to a disease with fever, hepatosplenomegaly (enlarged liver and spleen), mental or motor retardation, and sometimes death.

2. Acute acquired CMV infection. This syndrome is similar to infectious mononucleosis (caused by Epstein-Barr virus) and is characterized by fever, malaise, and muscle and joint pain but without sore throat.

Transmission may occur by sexual contact, in milk, via respiratory droplets among nursery or day care center workers, and by blood transfusions. CMV infection during pregnancy can be hazardous to the fetus, possibly leading to stillbirth, brain damage, and other birth defects, or to severe neonatal illness.

3. CMV infection in immunocompromised persons. This may affect transplant recipients and those infected with HIV. It may include CMV retinitis (an eye infection), gastrointestinal CMV, respiratory infection, and encephalitis (inflammation of the brain).


CMV infections occur worldwide. About 4 out of 5 people over age 35 have been infected with cytomegalovirus, usually during childhood or early adulthood. In most of these people, the disease is so mild that it is overlooked.

Transmission is sexual, congenital (at birth), through blood products or transplantation, and person-to-person (e.g., day care centers).


Most adults exhibit mild, nonspecific clinical signs and symptoms, or none at all. Some adults develop mononucleosis with 2 weeks of irregular high fever.

Immunodeficient patients and those receiving immunosuppressive therapy may develop symptoms of pneumonia (such as fever, cough, or dyspnea), or symptoms of other secondary infections, as mentioned above.


Diagnosis is made by medical history and physical examination. Blood tests may be performed.


Three antiviral drugs with efficacy against CMV include ganciclovir, foscarnet, and cidofovir. All three drugs need close monitoring to prevent kidney damage. A sustained-release ganciclovir implant has been shown to control disease in the implanted eye (but not elsewhere).

Additional treatment aims to relieve the symptoms and prevent complications.


Who is at risk for getting cytomegalovirus (CMV) infection?

How is CMV transmitted?

What precautions should be taken?

What treatment is available?

What are the side effects?

What special measures should be taken if a person is pregnant?

To help prevent CMV infection, follow these guidelines:

1. Warn immunodeficient patients and pregnant women to avoid any individuals with confirmed or suspected CMV infection. Maternal CMV infection can cause fetal abnormalities.

2. Urge patients with CMV infection to wash their hands thoroughly to prevent spreading it. It is especially important to stress this with young children, who are usually unconcerned about personal hygiene.

3. Be careful when handling urine and saliva or articles contaminated with these or other body secretions. Dispose of such articles properly. Mark contaminated linens for special handling.

4. Because of the risks of CMV during pregnancy, pregnant women should be counseled about the risks and the need to practice good hygiene.