Cytomegalovirus (CMV) is a common virus that can infect anyone. Once infected, your body retains the virus for life. Most people do not know they have CMV, because it rarely causes problems in healthy people. However, if you are pregnant, CMV is cause for concern because the infection can be transmitted to your baby. Congenital CMV (cCMV) is the most common non-genetic, and therefore preventable, cause of birth defects and hearing loss in infants.

  • 1 in 200 Canadian infants are infected with CMV during pregnancy.
  • 1 in 5 children with congenital CMV will have a permanent disability, such as hearing loss or developmental delay.
  • Young children infected with CMV usually have no symptoms and easily spread the infection to others through saliva and urine.
  • If a pregnant woman is living with a young child infected with CMV, her chance of developing the infection is 1 in 4.

Most babies with congenital CMV appear healthy at birth.

Some babies with congenital CMV who appear healthy at birth can develop signs over time — sometimes not for months or years after birth. The most common of these late-occurring symptoms are hearing loss and developmental delays.

Congenital CMV is the leading cause of non-genetic sensorineural hearing loss and a leading cause of intellectual disability.

Babies with congenital CMV who are sick at birth tend to have significant signs and symptoms, including:

  • Premature birth
  • Low birth weight
  • Yellow skin and eyes (jaundice)
  • Enlarged and poorly functioning liver
  • Purple skin splotches, or a rash, or both
  • Abnormally small head (microencephaly)
  • Enlarged spleen
  • Pneumonia
  • Seizures
Download Our CMV Fact Sheet

Careful hygiene is the best prevention against CMV. Health care workers and those who work with young children have the greatest opportunity for exposure.

Experimental vaccines are being tested for women of childbearing age. These vaccines may be useful in preventing CMV infection in mothers and infants, and reducing the chance that babies born to women who are infected while pregnant will develop disabilities.

If you have a compromised immune system, you may benefit from taking antiviral medication to prevent CMV disease.

You can take these precautions to help prevent CMV infection:

Wash your hands often.

Use soap and water for 15 to 20 seconds, especially if you have contact with young children or their diapers, drool or other bodily fluids. This is especially important if the children attend child care.

Avoid contact with tears and saliva when you kiss a child.

Instead of kissing a child on the lips, for instance, kiss on the forehead. This is especially important if you’re pregnant.

Be careful with disposable items.

When disposing of diapers, tissues and other items that have been contaminated with bodily fluids, be careful not to touch your hands to your face until after thoroughly washing your hands.

Avoid sharing food.

Sharing glasses and kitchen utensils can spread the CM Virus.
Clean toys and countertops often.
Clean any surfaces that come into contact with children’s urine or saliva.

Practice safe sex.

Wear a condom during sexual contact to prevent spreading CMV through semen and vaginal fluids.

Finding out that your child has congenital CMV can turn your whole world upside down. Most people have never even heard of CMV, let alone considered how a diagnosis could impact their family. If you are dealing with a new diagnosis, we are here for you. We understand what a confusing and scary experience it can be trying to navigate the medical system and determine the best course of action for your loved one. Know that there is an amazing community of CMV parents in Canada and our organization will ensure you find all of the resources and supports that you need.

If you don’t know where to start, start here. We have outlined all of the basic information and questions that parents want to know below. If you have any questions at any time, please do not hesitate to reach out to us at:

Whether you are years into your CMV journey or you just received a diagnosis, please consider joining our CMV Family Network by clicking the button below. You can connect with other families in your area who have shared similar experiences and support each other along the way.

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What is the Prognosis For a Baby Affected by cCMV?

Babies affected by cCMV have a wide range of lifelong effects. The majority of babies born with cCMV (4 out of 5) will be absolutely fine and go on to develop like any other child. Some babies have permanent effects that can range from hearing loss to cerebral palsy.

Without treatment, children with hearing loss will likely go on to continue to lose their hearing. It is very important for your child’s development to attend regular audiological exams.

Facing the unknown is hard. It helps to put things into perspective – take small steps and control what you can when it feels like everything else is uncontrollable.

Why Didn’t My Doctor or Midwife Find This Sooner?

Some symptomatic babies can be diagnosed while in utero, but most will not. Symptoms vary and quite often there simply aren’t any. In other cases, symptoms are very mild and are easily missed. In fact, 80% of symptomatic babies go undiagnosed.

Knowledge about cCMV amongst the general population is very low and 91% of mothers have never heard of the virus. CMV Canada is an actively working with the medical community trying to raise awareness with healthcare providers.


Newborns require treatment when they display signs and symptoms of cCMV infection. The type of treatment depends on the signs and symptoms and their severity.

The most common treatment is antiviral medication, which can slow the reproduction of the virus. Researchers are studying new medications and vaccines to treat and prevent CMV. If your newborn has tested positive for CMV, talk to your healthcare provider about antiviral medications.

Is Treatment Safe?

Antiviral treatment is generally safe, effective and well-tolerated. The most severe side effect is when the baby’s white blood cell count gets too low for them to fight off bacterial infection. Regular blood tests are required to help ensure they stay within a healthy range. There have been no cases of infertility or cancers as a result of treatment.

Parent Hacks For Administering Medication:

  • Put tape or clear nail polish on the outside of the syringe so that the numbers don’t wear off so quickly.
  • Put baby on their back when administering the medication.
  • Put syringe into the cheek at the back of the mouth and dispense slowly.
  • Have a paper towel ready.
  • Make sure to monitor your baby’s weight. If they have a growth spurt, see your doctor to get the dosage adjusted.
  • Don’t forget – you and your baby are learning how to do this! It takes practice and you will get there.
  • Canadian regulations for travelling with medication

Next Steps

If you suspect your baby has been infected with CMV, ask your healthcare provider about CMV testing.

If your baby has been diagnosed with CMV, ask your healthcare provider about antiviral treatment.

To join our Canadian CMV Family Network and stay up to date on all the latest news, sign up below:

Join our Family Network

The Canadian CMV Foundation was established with a vision in mind – to raise funds for research, to develop a vaccine and eradicate congenital CMV.

There is currently no vaccine available for CMV, but pharmaceutical companies have been making promising developments in this field.

Clinical research studies are now actively recruiting participants for Phase 3 CMV vaccine trials at 5 sites in Canada: Toronto, Burlington, Quebec, Montreal and Mirabel.

To learn more about these clinical trials, please contact Centricity Research:


And check out these resources:

To learn more about mRNA vaccines and Moderna’s vaccine development, click here.