You would never know nearly two-year-old Covie Fay was born with a dangerous virus.

"I only saw her for about 10 seconds and they rushed her into the intensive care nursery," recalled Covie's mother, Crystal Wade.

Covie had been infected with cytomegalovirus, or CMV.

"It's terrifying," Wade continued. "Absolutely terrifying."

"CMV is transmitted by close contact with bodily secretions," said Dr. Sallie Permar, a professor of pediatrics, immunology, and microbiology at Duke University.

Most people are asymptomatic, so mom may not even know she has the virus, posing a serious risk to her unborn baby.

"It can cause the same syndrome as Zika virus; the microcephaly, severe brain damage, hearing loss. In fact, it's been estimated to be the cause of 25 percent of childhood hearing loss," Permar said.

Pregnant women can pick up the virus simply by changing a diaper.

"So toddlers like to share their saliva, and we change their diapers, and they, when infected, can shed the virus very easily in those fluids," Permar continued.

Researchers at Duke University wanted to know how they could better protect moms and their babies from CMV. Permar and her team have successfully tested a CMV vaccine in animals. There's currently a simple way to test infants using a cotton swab to gather saliva.

Covie was tested and diagnosed at birth. She was given antivirals right away. Her mom believes that's what saved her child.

"Now, she's running around. She's climbing on anything and everything," Wade said happily.

She hopes that, one day, all babies will be tested for CMV.

Currently, more than a dozen states have enacted legislation mandating CMV testing for children who fail their hearing screening. The CMV vaccine is now moving on to human trials.