Overview
A cytomegalovirus (CMV) infection is a condition caused by a common virus. The CMV virus stays in the body for life after infection.
CMV spreads from person to person through body fluids. These include blood, saliva, urine, semen and breast milk.
Symptoms of a CMV infection can include a fever, fatigue and a sore throat. But the virus rarely causes symptoms in healthy people. If you're pregnant or if your immune system is weakened, CMV is cause for concern. Pregnant people with an active CMV infection can pass the virus to their babies. The babies might then have symptoms.
For people who have weakened immune systems, CMV infection can be fatal. The risk is especially high for people who've had an organ, stem cell or bone marrow transplant.
Lab tests of blood, saliva and urine can be done to find out if you have a CMV infection. Most often, healthy people don't need treatment for CMV infections. Others who become ill are prescribed medicines that help ease the symptoms.
Help limit the spread of CMV infections with good hygiene. Wash your hands often. Don't touch your face after handling used tissues or diapers. And don't share food, drinks or utensils.
Symptoms
Cytomegalovirus (CMV) infections can cause symptoms such as fever, tiredness and a sore throat. But most healthy people who are infected with CMV have no symptoms.
People who are more likely to have symptoms of a CMV infection include:
- Newborns who became infected with CMV before they were born. This condition is called congenital CMV.
- Infants who become infected during birth or shortly afterward, also called perinatal CMV. This group includes babies infected through breast milk.
- People who have weakened immune systems. This includes people who've had an organ, bone marrow, or stem cell transplant, or those who have HIV.
CMV infection can cause illness when you're first infected. This is called a primary infection. The risk of a baby being born with CMV is higher when the pregnant parent gets a primary infection. If you're healthy, CMV mainly stays dormant. That means the virus doesn't become active and make copies of itself. But in people with weakened immune systems, CMV can become active again when the body's defenses can't keep it dormant.
Babies
Most babies who have congenital CMV appear healthy at birth.
A few babies with congenital CMV who appear healthy at birth get symptoms over time. Sometimes, the symptoms start months or years after birth. The most common of these late symptoms are hearing loss and delays in development. A small number of babies also may develop vision loss.
Babies with congenital CMV who are sick at birth can have symptoms or conditions that include:
- Low birth weight.
- Yellow skin and eyes, called jaundice — this may be harder to see on darker skin.
- Damage to the retina of the eye, called retinitis.
- Rash or pinpoint round spots on the skin.
- A head that is smaller than is typical, also called microcephaly.
- Enlarged spleen.
- Pneumonia.
- Seizures.
- Development and motor delays.
Babies with congenital CMV who have symptoms also might be more likely to be born premature.
People who have weakened immune systems
In people with weakened immune systems, CMV can lead to conditions that affect the:
- Eyes.
- Lungs.
- Liver.
- Esophagus.
- Stomach.
- Intestines.
- Brain.
Healthy adults
Most healthy people who are infected with CMV have few if any symptoms. When first infected, some adults may have symptoms such as:
- Fatigue.
- Fever.
- Sore throat.
- Headache.
- Swollen glands.
When to see a doctor
See your healthcare professional if:
- You have a weakened immune system and you get symptoms of a CMV infection. Without treatment, CMV infection can be serious or even fatal for some people who have weakened immune systems. Those who've gotten stem cell or organ transplants seem to be at greatest risk.
- You are pregnant and you become ill with symptoms such as fever, fatigue, sore throat or swollen glands.
If you have mild symptoms of a CMV infection but are healthy, you likely won't need treatment. Your healthcare professional might simply tell you get plenty of rest.
When your baby or young child should see a doctor
If you know you were infected with CMV during your pregnancy, tell your child's healthcare professional. Your child likely will be tested for hearing or vision problems.
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Causes
A cytomegalovirus (CMV) infection is caused by a virus of the same name. When CMV is active in your body, you can pass the virus to other people. The virus is spread through body fluids. These include blood, urine, saliva, breast milk, tears, semen and vaginal fluids. Casual contact doesn't spread CMV.
Ways the virus can be spread include:
- Hand to face contact. For example, touching your eyes or the inside of your nose or mouth after touching the body fluids of an infected person.
- Sexual contact with an infected person.
- The breast milk of an infected mother.
- Organ, bone marrow or stem cell transplants or blood transfusions.
- Birth. A pregnant person with CMV can pass the virus to the baby before or during birth. The risk is higher if you get CMV for the first time during pregnancy.
Risk factors
There are no key risk factors for cytomegalovirus (CMV) infections. CMV is a widespread and common virus that can infect almost anyone. For instance, 1 in 3 children in the United States get the infection by age 5. More than half of adults become infected by age 40.
Complications
Medical conditions called complications that are linked with cytomegalovirus (CMV) infection vary. The possible complications depend on your overall health and when in life you were infected.
Healthy adults
It's common for CMV to cause healthy adults to get another illness that spreads from person to person called mononucleosis. Less often, CMV can cause healthy adults to get an enlarged spleen, inflamed liver or certain blood conditions. Rare complications include conditions that affect the brain, lungs, nerves and heart muscle.
People who have weakened immune systems
Health conditions that stem from CMV infections can include:
- Vision loss due to swelling called inflammation in the light-sensing layer of the eye. This condition is called retinitis.
- Digestive system conditions. These include swelling of the colon called colitis, swelling of the esophagus called esophagitis and swelling of the liver called hepatitis.
- Nervous system problems, including brain inflammation called encephalitis.
- An infection in one or both lungs called pneumonia.
Infants who have congenital CMV
An infant whose mother first became infected with CMV during pregnancy is more likely to experience complications. Complications for the baby can include:
- Hearing loss.
- Delays in development or skills related to movement.
- Vision loss.
- Seizures.
- Lack of coordination.
- Weakness or problems using muscles.
Prevention
Careful hygiene is the best way to help prevent cytomegalovirus (CMV) infections in people who haven't already been infected. You can take these steps:
- Wash your hands often. Scrub with soap and water for 20 seconds. Wash after you change a diaper, help a child use the toilet or handle toys. Also wash if your child's saliva gets on your hands. These steps are very important if your child goes to daycare.
- Stay away from tears and saliva when you kiss your child. Instead of kissing your child on the lips, for instance, kiss on the forehead. This is very important if you're pregnant.
- Do not share food or drink out of the same glass as other people. Sharing glasses and kitchen utensils can spread CMV.
- Be careful with disposable items. Don't touch your face right after you throw out diapers, tissues and other items with bodily fluids on them. Wash your hands well before you touch your face.
- Clean toys and countertops. Clean any surfaces that come in contact with children's urine or saliva.
- Have safe sex. Use a new condom each time you and your partner have sex. This helps prevent the spread of CMV through semen and vaginal fluids.
If you have a weakened immune system, your healthcare professional may recommend antiviral medicine to prevent a CMV infection. Often, this medicine is prescribed to people who get stem cell transplants.
Vaccines for CMV aren't yet available. But they're being tested for young women. Someday, vaccines may help prevent CMV infection in pregnant people and infants. They also might lower the chances that babies born to pregnant people with CMV will develop long-term health conditions.