After Michelle Longo gave birth to her third son, she noticed some unusual bruising on him. At the time, she didn’t know that the bruises were a sign that he had a little known condition.

“They said, ‘Third baby, quick labor; it was probably just bruising from coming down the birth canal,’” Longo, 35, from Swedesboro, New Jersey, told CIDRAP News. “Nobody said anything. He started feeding fine. It was good.” 

But he failed a hearing test on his right side. Again, doctors and nurses attributed it to her delivery and fluid in his ear. Still, they urged the family have him undergo an auditory brainstem response test, which measures the auditory nerves. 

“He kept failing,” Longo said. “The audiologist said, ‘You guys should really just go to CHOP [Children’s Hospital of Philadelphia].’”

At CHOP, her son failed numerous hearing tests, and genetic tests did not reveal an underlying cause for his hearing loss. Then an otolaryngologist asked the family a question that changed their lives. 

“He was the first one to say, ‘Have you guys ever heard of CMV?’” Longo said. “Of course, we hadn’t.” 

CMV, or cytomegalovirus, is a common virus that’s often harmless in adults. “It usually causes absolutely no symptoms,” said Megan Pesch, MD, associate professor and director of the CMV Developmental Follow-up Clinic at the University of Michigan. “But if you are pregnant… it can transmit through the placenta and cause a lot of damage to that fetus.” 

Babies with moms who had a CMV infection during pregnancy are born with congenital CMV (cCMV), which can cause complications such as miscarriage, stillbirth, hearing loss, vision problems, epilepsy, learning disabilities, cerebral palsy, and autism. Most children born with CMV (roughly 75%) never develop complications, but for the other 25%, prompt diagnosis means they can undergo antiviral treatment that can slow their hearing loss. 

Two papers published in the journal Pediatrics examine possible screening methods for CMV. One looks at Connecticut’s hearing-targeted screening program, and the commentary urges universal screening from a blood spot test. Treating more symptomatic babies with CMV could also have a huge impact on how these babies develop. 

“Most cases of CMV in the absence of a screening program are not diagnosed,” said Pesch, coauthor of the commentary. “We need more babies to be identified.” 

In the paper, researchers at Yale University looked at the impact of a state mandate on diagnosing babies with cCMV. In 2016, Connecticut required doctors to test all babies who failed their hearing test for the virus.