Cytomegalovirus (CMV)

Baby with bright eyes

Cytomegalovirus, or CMV, is a common virus that infects people of all ages. Once CMV is in a person’s body, it stays there for life and can reactivate. A person can also be reinfected with a different type of the virus.

Most people infected with CMV show no signs or symptoms. That’s because a healthy person’s immune system usually keeps the virus from causing illness.

When a baby is born with CMV infection, it is called congenital CMV. Most babies with congenital CMV infection never show signs or have health problems. However, some babies can have health problems that are apparent at birth or that develop later during infancy or childhood.


Key Facts

  • If you are pregnant and get infected with CMV, you can pass the virus to your baby during pregnancy.
  • CMV is the most common infectious cause of birth defects in the United States.
  • Most babies with congenital CMV never show signs or have health problems.
  • Some babies can have hearing loss at birth or can develop it later.
  • One out of five babies with congenital CMV will have symptoms or long-term health problems.


Prevention Tips

  • Parents and childcare providers can lower their risk of getting CMV by reducing contact with saliva (spit) and urine from babies and young children. Do not share food, utensils, or cups with a child. Wash your hands with soap and water after changing diapers or helping a child to use the toilet.
  • Medicines called antivirals might improve hearing and developmental outcomes in some infected babies who show signs of congenital CMV infection at birth.
  • Babies with congenital CMV infection, with or without signs at birth, should have regular hearing checks.

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