Cytomegalovirus (CMV)
6-minute read
Key facts
- Cytomegalovirus (CMV) is a very common infection caused by a virus in the herpes family.
- CMV infections don't usually cause any symptoms in people with healthy immune systems.
- People with a weakened immune system often get a fever and can become seriously ill with CMV.
- CMV can be passed from pregnant people to their baby.
- The best way to prevent CMV is through good hand washing.
What is CMV?
Cytomegalovirus (CMV) is a very common infection. People with normal immune systems often have no symptoms. But the infection can cause serious problems in:
- people who are pregnant and pass it on to their baby
- those who have a weakened immune system
Around 1 in 2 people have been infected with CMV by early adulthood. By 40 years of age, more than 8 out of 10 people will have been infected with CMV.
Like other herpes viruses, CMV stays in your body and becomes ‘latent'. It may reactivate later in life.
Reactivation can happen during pregnancy or when you have a weakened immune system. This may be due to medicines or a disease, like AIDS.
What are the symptoms of CMV?
In people with a healthy immune system, CMV usually doesn't cause any symptoms.
If you do get symptoms with CMV, you may have:
People with a weakened immune system often get a fever. They can become seriously ill.
Your immune system may be weak due to:
- HIV infection and AIDS
- chemotherapy
- taking medicines that suppress your immune system
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What causes CMV?
Cytomegalovirus is a very common virus in the herpes virus family.
How is CMV spread?
CMV is transferred easily from person to person through body fluids. The virus can be found in:
- blood
- breast milk
- nasal mucous (snot)
- saliva
- semen
- urine (wee)
- vaginal secretions
CMV can be spread through:
- close physical contact — kissing and sex
- blood transfusions
- organ and cell transplants
- from mother to baby in the womb
When should I see my doctor?
You should see your doctor if you have symptoms of cytomegalovirus and:
- you're pregnant
- you have a weakened immune system
FIND A HEALTH SERVICE — The Service Finder can help you find doctors, pharmacies, hospitals and other health services.
How is CMV diagnosed?
Your doctor may arrange tests to find out if you have CMV.
CMV testing may be recommended if you are pregnant and have frequent contact with large numbers of young children.
ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.
How is CMV treated?
Most people recover from CMV without any special treatment, just like when you have a cold.
If you have a weakened immune system, your doctor may prescribe antiviral medicines.
If you are pregnant and have CMV, see your doctor for advice.
What are the complications of CMV?
If you become infected with CMV while you're pregnant, there is a chance that your unborn baby will also become infected. Once your baby is born your doctor will check to see if the infection has been passed to your baby.
Newborns can be given antiviral medicines. The earlier the treatment is started the better the outcome.
Most babies will be born healthy, but a few develop long-term problems. This is called congenital CMV. The most common problem is hearing loss. Other possible problems are:
- cerebral palsy
- developmental delay
- intellectual disability
- microcephaly (small head size)
- vision loss
People with weakened immune systems may develop CMV infections of the:
- blood
- bowel
- central nervous system
- eyes
- kidneys
- liver
- lungs
Can CMV be prevented?
The best way to prevent CMV when you are pregnant or trying to conceive is through good hand hygiene.
If you are pregnant and have contact with young children, the following tips may lower your chances of catching CMV:
- Avoid sharing food, utensils or toothbrushes.
- Wear gloves while changing nappies.
- Avoid contact with saliva — don't put your baby's dummy in your mouth.
- Clean toys and surfaces that might have been in contact with saliva or urine.
If you're at risk from CMV due to a weakened immune system, your doctor may prescribe antiviral medicines. There is no vaccine available to prevent CMV infection.
Resources and Support
If you are worried about CMV, call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.