About cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a herpes virus. It’s related to the herpes viruses that cause cold sores, glandular fever and chickenpox.

CMV is very common, especially in young children. About 50% of people get CMV by early adulthood.

CMV is contagious. It spreads through contact with an infected person’s body fluids, including saliva, wee, poo, mucus, tears, breastmilk and semen.

During pregnancy, CMV can also pass from women to their unborn babies through the placenta. This is called congenital CMV infection.

In most healthy children and adults including pregnant women, CMV infection causes mild flu-like symptoms or no symptoms at all. But CMV can cause serious illness in people with very weak immune systems. It can also cause developmental concerns, developmental delay or disability in some babies born with the infection.

Once you get the CMV virus, it stays in your body for life. Most of the time the virus is ‘sleeping’ in your body, but it can wake up at any time. When the virus wakes up, it doesn’t usually cause symptoms in healthy people.

Around one-third of children who go to child care have CMV. After initial infection, these children can have CMV in their saliva, wee and other body fluids for up to 2 years. This means that early childhood educators and carers are at high risk of CMV infection and should maintain good hygiene to avoid infection. This is particularly important for educators and carers who are pregnant or planning a pregnancy.

Signs and symptoms of cytomegalovirus (CMV)

For children and adults, including pregnant women, cytomegalovirus (CMV) might cause mild flu-like signs and symptoms, including runny nose, sore throat, fever and cough. Flu-like symptoms usually go away after a few weeks.

The signs and symptoms of CMV in babies born with the infection are different from the signs in children and adults. These signs include petechial rash, jaundice and microcephaly. Also, some babies born with CMV are born small for gestational age.

Only around 10% of babies born with CMV show signs of the infection at birth.

If you’re pregnant and you feel unwell or are concerned that you might have CMV, see your midwife, obstetrician or GP. These health professionals can work out whether you’re at high risk of getting CMV and organise CMV testing if you need it.

Complications of cytomegalovirus (CMV)

It’s rare for pregnant women with cytomegalovirus (CMV) to get very sick or develop long-term health complications.

Most babies born with CMV stay well. But CMV can damage an unborn baby’s developing brain. This means that some babies born with CMV have developmental concerns, developmental delay or disability.

Hearing loss is the disability most commonly caused by CMV. But it can also cause intellectual disability, cerebral palsy and epilepsy.

Some unborn babies and newborns can die because of CMV, but this is rare.

Unborn babies who get CMV in the first trimester of pregnancy are more likely to develop disability than unborn babies who get CMV in the second or third trimester. And babies born with CMV who show signs of the infection at birth are more likely to develop disability than those who show no signs of the infection.

Diagnosing cytomegalovirus (CMV)

Pregnant women
Routine testing for cytomegalovirus (CMV) infection in pregnancy isn’t currently recommended in Australia.

Your midwife, obstetrician or GP might recommend that you get a blood test to check for CMV infection if:

• You’re pregnant or planning a pregnancy, and you care for or work with young children.
• You’re pregnant and have signs or symptoms of a viral infection.

If either of these sound like you and your health professional doesn’t offer you a CMV test, you can ask for one.

Newborn babies
Routine newborn screening in Australia doesn’t include CMV. But some newborns are tested for CMV because their mothers had a CMV infection in pregnancy or because they:

• are unwell at birth
• didn’t pass the newborn hearing screening.

If your newborn needs to be tested for CMV, a doctor or nurse will take a saliva or wee sample from your baby within the first 3 weeks of their birth.

Treatment for cytomegalovirus (CMV)

Pregnant women
If you’re diagnosed with cytomegalovirus (CMV) in pregnancy, your midwife, obstetrician or GP or an infectious disease specialist will explain your options, including antiviral medicine. Antiviral medicine has some risks for pregnant women and their babies, so it’s important to talk with the specialist about the best thing for you and your baby.

If you have flu-like symptoms, you can try the following:

• Take paracetamol for pain.
• Drink plenty of fluids – for example, water or oral rehydration fluids.
• Have soothing drinks like honey and lemon teas, or suck throat lozenges for a sore throat.
• Try a saline nasal spray or steam for a blocked nose.
• Get plenty of rest.
• Do gentle physical activity if you feel up to it.

Newborn babies
If your baby is diagnosed with CMV at birth and shows signs of the infection, a paediatric infectious disease specialist might recommend antiviral medicine for your baby.

If your baby is diagnosed with CMV at birth but doesn’t show any signs of the infection, your baby probably won’t need any immediate medical treatment.

All babies diagnosed with CMV at birth should have a newborn hearing screen within the first month of life. These babies should also see an audiologist for regular hearing tests.

All babies diagnosed with CMV at birth should see a paediatrician for regular health check-ups until they’re 5 years old. Your baby might need to see the doctor every 3-6 months, depending on their health and development.

If you have CMV, it’s usually OK to breastfeed your baby. If your baby was born very premature (less than 30 weeks) or with a low birth weight (less than 1500 g), it’s best to talk with your midwife, obstetrician or GP about breastfeeding your baby.

Prevention of cytomegalovirus (CMV)

There’s currently no vaccine that can prevent cytomegalovirus (CMV).

The best way to reduce your risk of getting CMV in pregnancy is by maintaining good hygiene:

• Wash your hands regularly with warm, soapy water for at least 15 seconds, especially after changing nappies, wiping children’s noses, and handling children’s toys and dummies.
• Avoid kissing your child on or near the lips. Instead, you could kiss your child on the forehead.
• Avoid sharing food, drinks, cutlery, toothbrushes or dummies with young children.