General Condition Information
Birth Prevalence
- 1 in every 200 babies is born with a congenital cytomegalovirus infection (around 20,000 babies each year in the United States).
- About 1 in 10 babies with congenital cytomegalovirus will have health problems (about 2,000 babies each year).
- Visit the Centers for Disease Control and Prevention to learn more about how often congenital cytomegalovirus occurs.
Screening Finding
What is congenital cytomegalovirus
Cytomegalovirus (CMV) is a type of herpes virus. It is very common for children and adults to catch CMV (called acquired CMV). Most people do not know that they have had a CMV infection because it usually causes no symptoms. Once a person is infected with CMV, the virus stays in their body for life.
When a baby is born with CMV infection, it is called congenital CMV. This happens when a pregnant mom passes CMV to the baby during pregnancy. Most babies who are infected with CMV before birth never develop any health problems. However, some babies who are infected with CMV will be born with health problems or develop health problems later in childhood. In these cases, the CMV infection can cause damage to the brain, ears, and other organs. This damage leads to the signs and symptoms of this condition seen in some babies.
Newborn Screening and Follow-Up
Newborn screening for congenital CMV can be done by checking your baby’s saliva, urine, or blood for the CMV virus. Screening before your baby is 21 days old is important to determine if the CMV infection is congenital or acquired. Congenital CMV can cause health problems and hearing loss, but acquired CMV usually does not.
Newborn screening for congenital CMV may be universal or targeted. In universal CMV screening, all babies are screened for the CMV virus. In targeted CMV screening, only those babies who show symptoms or who do not pass their Newborn Hearing Screening are screened for CMV.
If your baby’s CMV screen is positive, your baby’s health care provider will contact you. Together, you will discuss next steps and follow-up plans.
A positive CMV screening result does not mean that your baby will have or develop health problems. It does mean that your baby needs more follow-up testing.
Your baby may need the following tests after a positive CMV screening result:
- Blood and/or urine tests
- Hearing tests
You should complete any recommended follow-up testing as soon as possible. Babies with this condition may develop health problems if they are not diagnosed and treated.
False-positive screening results for CMV can and do happen. The screening results can be affected if the saliva sample was taken from the baby too soon after breast feeding.
Condition Details
Newborn screening helps babies lead healthier lives. If your baby has a positive CMV result, follow up with your health care provider quickly. It is important to follow their instructions. Most babies with CMV will have no health problems and will never need any treatment. Your baby may need to get treatment if they start to experience symptoms. If your baby is not showing signs or symptoms, close follow-up is important. In some cases, your baby’s health care provider may decide it is best to watch (monitor) your baby to decide next steps. Careful monitoring and early treatment if needed will help your baby stay as healthy as possible.
About 1 out of 10 babies with CMV will have signs and symptoms at birth. The most common health problem in babies with CMV is hearing loss. Some babies without signs of CMV infection at birth may have hearing loss. Hearing loss may develop later, even in babies who have passed the newborn hearing test. Hearing loss will eventually occur in about half of the children with symptoms of CMV infection at birth and up to 15% of those with no symptoms.
Signs of congenital CMV may include the following:
A pregnant woman can pass CMV to her unborn baby. CMV in the woman’s blood can cross through the placenta and infect the baby.
If a mother is infected with CMV for the first time during pregnancy (called a primary infection), the chance of transmission to the baby is the highest. These babies are also more likely to have symptoms at birth, especially if they are infected in the first trimester.
If a mother has been infected with CMV in the past, the chance of transmission to the baby is much smaller. If transmission occurs, the baby is less likely to have symptoms at birth. This is true even if the mother is re-infected with a different strain of CMV.
CMV is not inherited through a person’s genes, so other family members do not have an increased chance of congenital CMV.
Young children are a common source of CMV. Caregivers of young children are more likely to become infected with CMV.
There are a number of ways you can reduce your chance of getting CMV. This is especially important when you are pregnant:
- Do not share food, utensils, or cups with a child
- Do not put a pacifier in your mouth
- Do not share a toothbrush
- Avoid kissing children under 6 years old on the lips or cheeks
- Wash your hands after changing diapers, feeding a child, or wiping a child’s face
Treatment and Management
Most babies with a congenital CMV infection will not need treatment. It is important to talk to your health care provider about which treatment(s) are best for your baby. The goal of treatment is to prevent the health problems this infection causes.
Treatment options can include the following:
- Regular hearing tests to check for hearing loss
- Regular vision tests to check for vision loss
- Antiviral medications