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Español: Información general

Cytomegalovirus (CMV) is one of the herpesviruses. This group of viruses includes the herpes simplex viruses, varicella-zoster virus (which causes chickenpox and shingles), and Epstein-Barr virus (which causes infectious mononucleosis, also known as mono). CMV is a common infection that is usually harmless. Once CMV is in a person's body, it stays there for life. Among every 100 adults in the United States, 50–80 are infected with CMV by the time they are 40 years old.

Most healthy children and adults infected with CMV have no symptoms and may not even know that they have been infected. Others may develop a mild illness when they get infected and have the following symptoms: fever, sore throat, fatigue, and swollen glands. But since these are also symptoms of other illnesses, most people don't realize that they have been infected with CMV.

CMV can cause serious disease in people with a weakened immune system. See People with Weakened Immune Systems.

Trends and Statistics: How Many Babies Are Affected by Congenital CMV Infection?

Congenital CMV Infection

Cytomegalovirus can also cause serious disease in babies who were infected with CMV before birth (referred to as congenital CMV infection). About 1 in 150 children is born with congenital CMV infection. And about 1 of every 5 children born with congenital CMV infection will develop permanent problems (such as hearing loss or developmental disabilities) due to the infection. Infants and children who are infected with CMV after birth rarely have symptoms or problems. See Congenital CMV Infection for more information.

Spread of CMV and Tests for CMV Infection

CMV is spread by close contact with a person who has the virus in his or her saliva, urine, or other body fluids. CMV can be transmitted from a pregnant woman to her fetus during pregnancy. For more information, see Transmission.

Most CMV infections are not diagnosed because CMV usually causes few, if any, symptoms. A blood test can tell whether a person has ever been infected with CMV.

CMV infection at birth (congenital CMV infection) can be diagnosed in an infant if the virus is detected in his or her urine, saliva, or blood within 2-3 weeks after birth. For more information about diagnosing cytomegalovirus and congenital CMV infection, see Testing and Diagnosis.

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Treating CMV Infection

Healthy people who are infected with CMV but who have no symptoms usually do not require medical treatment.

There is no drug licensed to treat congenital CMV infection. There are limited data on the use of antiviral medications in infants with symptomatic congenital CMV infection with central nervous system involvement. Pediatricians and other specialists play an important role in making sure that children with congenital CMV infection are assessed and treated as needed. For more information, see Treatment for Babies Born with CMV.

Vaccine Research

There is no available vaccine for preventing congenital (present at birth) CMV disease. However, a few CMV vaccines are being tested in humans, including live attenuated (weakened) virus vaccines and vaccines that contain only pieces of the virus. The Institute of Medicine has ranked the development of a CMV vaccine as a highest priority because of the lives it would save and the disabilities it would prevent. It may be a number of years before there is a Food and Drug Administration-approved CMV vaccine.

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