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Newborn Screening Ontario
Hearing Loss Risk Factor Screening

CMV Screen Positive

What is CMV and how common is it?

Cytomegalovirus (CMV) is a common virus.  About 1 in 3 (33%) children have had CMV by 5 years of age and by adulthood most people have had the infection. Most healthy children and adults who get CMV don’t even know it because they don’t have any signs or symptoms. However, when a pregnant woman is infected with CMV there is a chance it could be passed to the baby.  When this happens and a baby is born with CMV it is called congenital CMV infection, or cCMV for short. In Ontario, about 1 in 200 babies are born with cCMV. 

What does a “positive” CMV screening result mean?

A positive CMV screening result means that a baby has a high chance of having a cCMV infection. Most babies with cCMV do not have any signs of the infection and remain healthy, but some can have problems and treatment may be an option. An assessment by a pediatrician or ID doctor is needed to find out if the baby has any signs of the infection.

What does the assessment for cCMV include?

Babies who have a CMV screen positive result are referred to a pediatrician or ID doctor for an assessment that includes confirmatory urine CMV testing, a physical exam, blood tests, eye exam and head imaging to find out if the baby has any signs or symptoms of cCMV. A detailed hearing test is also arranged by the Infant Hearing Program. The results of these tests help figure out if the baby may benefit from treatment, and what other follow-up may be suggested.

If your baby has a CMV screen positive result, you may find the additional resource helps answer some of your questions:

My Baby Has a Positive Cytomegalovirus (CMV) Screening Result

Mon bébé a eu un résultat positif au cours d’un examen de dépistage du cytomégalovirus (CMV)