Testing for Congenital Cytomegalovirus (cCMV)

This leaflet is for the parents of babies, who have been referred for a full diagnostic test with audiology following the newborn hearing screen.

It will explain the link between a condition called Cytomegalovirus (cCMV) and permanent hearing loss. It also explains how your baby is tested for cCMV and what to expect subsequently.

What is Congenital CMV?

Cytomegalovirus (CMV) is a common virus that is usually harmless to adults. However, if a mother develops this infection during her pregnancy and a baby is exposed to the virus before they are born there is a risk of long-term side effects. This is called congenital CMV.

What does the test involve?

A small swab (similar to a cotton bud) will be placed gently into your babies’ mouth against the cheek to collect saliva. This will then be sent to a specialist laboratory to test for the virus.

Why does my baby require this screen?

Most babies with cCMV are otherwise well with no signs of infection. Your baby has been referred to audiology for a full diagnostic hearing test after not having a clear response on the new born hearing screen.

One in 15 babies who are referred to audiology are diagnosed with a permanent hearing loss in one or both ears, although there are many causes for hearing loss in babies, one possible cause is CMV, it thought up to one in four babies diagnosed with a hearing loss have had cCMV.

Can you treat cCMV?

Research studies show antiviral medication can help some babies with congenital CMV. In some cases, the medicine can stop hearing loss progressing or may even improve it. It is believed that medicine needs to be given early, preferably within the first four weeks of age.

What if my baby does not have CMV?

If your baby does not have cCMV, you will be notified in a letter from the hospital stating your baby does not have cCMV. It is important your baby still attends the full diagnostic test at audiology as they did not have clear responses during their hearing screen.

What if my baby does have cCMV?

If your baby does have cCMV you will be contacted by a specialist doctor of audiovestibular medicine to arrange further appointments to discuss treatment options for your baby.