Congenital CMV infection is the most common cause of non-hereditary hearing loss in children. It is estimated that cCMV infection accounts for ~25% of hearing loss in chlidren by the age of 4 years.
It is unknown why the virus causes hearing impairment in some children but not others. The chance of developing sensorineural hearing loss with cCMV infection is 30-50% for symptomatic children and 8-12% for asymptomatic children.
The hearing loss associated with cCMV infection can:
- affect one or both ears
- affect some or all pitches
- be mild to severe
- be congenital or present later
- be progressive and fluctuating
The Infant Hearing Program (IHP) has guidelines in place for children confirmed to have cCMV:
- Children with cCMV who have confirmed hearing loss will be assessed at least every 3 months for the first year, every 6 months for the second year, and once a year afterwards by IHP audiology
- Children with cCMV who have a normal hearing assessment will be assessed every 4 months for the first year, then at 18 months, 3 years and 5 years by IHP audiology.