Cytomegalovirus, or CMV, is a common virus that infects people of all ages. After CMV is in a person’s body, it stays there for life and can reactivate, however most people infected with CMV show no signs or symptoms.

About Cytomegalovirus

In the United States, nearly 1 in 3 children are already infected with Cytomegalovirus (CMV) by age 5. Over half of adults have been infected with CMV by age 40. Most people infected with CMV show no signs or symptoms because a healthy immune system usually keeps the virus from causing illness. However, CMV infection can cause serious health problems for people with weakened immune systems, as well as babies infected with the virus before they are born. For more information, download our CMV brochure and CMV fact sheet.

Congenital CMV

When a baby is born with CMV infection, it is known as congenital CMV. Some babies will not show any signs of infection, but others may show some or all of the following symptoms at birth:

  • Failed hearing screening
  • Low birth weight
  • Small head size (microcephaly)
  • Jaundice (yellowing of skin)
  • Seizures
  • Tiredness (lethargy)
  • Enlargement of the liver and spleen
  • Eye problems
  • Brain imaging abnormalities
  • Rash

Children born with congenital CMV infection are more likely to develop permanent disabilities in their first few years of life if they showed symptoms at birth. These disabilities may include:

  • Hearing loss
  • Vision loss
  • Mental disability
  • Lack of coordination
  • Seizures
  • Death (in rare cases)

Some babies without symptoms of congenital CMV at birth may later develop hearing loss.

Testing and treatment

The CDC does not recommend routine screening for CMV infection during pregnancy, but a woman who is pregnant or planning to become pregnant should talk to her doctor if she is concerned about CMV infection. A pregnant woman should consult with her doctor if she experiences illness such as a fever, swollen glands, stiff joints, and muscle aches.

Generally, pregnant women with CMV infection are treated only for their symptoms (e.g., acetaminophen for fever) and not for the virus itself. Antiviral medications currently available for CMV infection have serious side effects, are not approved for use in pregnant women, and have not been shown to prevent CMV infection in the fetus.

Babies with suspected congenital CMV infections should be evaluated by physicians who specialize in these infections to discuss the care and additional services the child may need. Babies with congenital CMV infection, with or without signs at birth, should have regular hearing checks and should be watched closely for normal growth and development. For more information download our CMV brochure and CMV fact sheet.

Cytomegalovirus prevention

While you cannot completely eliminate all risks of catching CMV, there are measures that can be taken to reduce your chances of getting it. If you are pregnant or planning to become pregnant, the best way to protect your baby from congenital CMV is to protect yourself:

  • Wash your hands often with soap and water for 15-20 seconds, especially after changing diapers, feeding a young child, wiping a young child's nose or drool, and handling children's toys.
  • Wear gloves when changing diapers or touching bodily fluids such as urine, vomit, or saliva.
  • Don't share food, drinks, eating utensils, or a toothbrush with a child.
  • Do not put a child's pacifier in your mouth.
  • Use soap and water or a disinfectant to clean toys, countertops, or other surfaces that may have a child's saliva or urine on them.
  • Avoid contact with a child's saliva when kissing or snuggling.
mother and sleeping baby
CMV Materials
View and download the CMV brochure and/or fact sheet
By the Numbers
1 in 3
Children are already infected with Cytomegalovirus by age 5
Of adults have been infected with CMV by age 40

CDC resources

External Resources
Learn more about Cytomegalovirus (CMV), a common virus for people of all ages.

Idaho-specific resources

External Resources
The Idaho CMV Advocacy Project is dedicated to educating Idaho women and families about the risks of Cytomegalovirus (CMV) during pregnancy and prevention strategies.
External Resources
The department shall make the following information to the public, particularly pregnant women and women who may become pregnant.
By the Numbers
1 in 200
Babies are born each year with congenital CMV
Idaho babies born with CMV annually
1 in 5
Babies born with congenital CMV develop long-term health problems
Contact Us
Idaho Maternal and Child Health