Congenital CMV is a common cause of permanent hearing loss and intellectual disability, but is treatable if caught early.
The timing could not have been better for the launch of a new program to test for a common cause of hearing loss in newborns at BC Children’s and Women’s Hospitals, as May is Speech and Audiology Awareness Month.
The BC Early Hearing Program (BCEHP) works with Dr. Soren Gantt and BC Women’s to test for congenital cytomegalovirus (CMV) infection in all newborns found to have hearing impairments during screening.
CMV is a virus that can cause hearing loss and other neurologic problems when infection occurs in utero, but is treatable if caught early. Newborns in the Neonatal Intensive Care Unit (NICU) will also be tested as they are at higher risk for having congenital CMV.
“Roughly 300 babies a year are born with CMV in British Columbia, but because most of them don’t have obvious symptoms they usually are not diagnosed without a screening program,” explains Dr. Gantt, a pediatric infectious disease specialist at BC Children’s Hospital and senior associate clinician scientist at the Child and Family Research Institute. “It’s a common virus, and about half of all adults in North America carry it unawares. However, over 20 per cent of babies with congenital CMV will develop hearing loss.”
The BCEHP is the province-wide screening and intervention program to check hearing for babies born in BC. “Currently over 97 per cent of babies born in BC are screened for hearing loss,” says Diane Bremner, Director of BCEHP. “Shortly after a baby is born, we test their hearing using soft sounds that are played into the baby’s ears while a computer measures the response.
This shows how well a baby's ears respond to sounds.” If the baby does not pass the hearing screening, they are brought in for a full hearing assessment at two to three months of age. This new pilot program will ensure that babies who test positive for CMV receive a hearing assessment and medical evaluation within three weeks. That way, if hearing loss or other problems are identified, treatment for CMV can be provided.
CMV can be easily tested for using a baby’s saliva and is treated easily with oral medication, taken twice a day for six months. “This treatment has been shown to improve or even normalize hearing in many cases,” says Dr. Gantt. “It even appears to improve cognitive development. But the key is to detect and treat babies affected by congenital CMV at the earliest stage possible. That’s the objective of this new screening program.”
CMV screening in newborns has never been done in BC before, and the collaboration between BCEHP, Dr. Gantt and his research team, and BC Women’s is the first of its kind in Canada. “CMV is a major unaddressed public health issue,” Dr. Gantt says. “We hope we’ll be able to help other hospitals in the province roll out this testing program in the near future, so that all babies can be tested – and given appropriate treatment – early.”
Diane of BCEHP agrees. “The BC Early Hearing Program works towards achieving the best language outcomes for all young children in BC,” she says. “We view this pilot project as a real opportunity to reduce hearing loss in newborn babies, and are thrilled to be a part of such an important program.”