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Risks of CMV or Cytomegalovirus

Pregnant woman

Most pregnant women understand the many dangers associated with consuming certain substances or contracting certain illnesses while pregnant and take precautions to avoid them. In 2015, the Zika virus made lots of headlines, with an outbreak of the mosquito-borne disease causing microcephaly and other complications in babies in utero when their mother was infected. Zika attracted enough attention that many pregnant women started avoiding mosquitos altogether in affected areas. But a more common illness—cytomegalovirus, or CMV—can cause similar problems for gestating babies. And many women are totally unaware of it.

A Common Virus

CMV is actually a version of the herpes virus, similar to the common chicken pox disease found around the world. Most people will contract the disease at some point in their lives, but in most cases, it only manifests as a cold. However, when a pregnant woman is actively infected by CMV, it can cause real damage.

"CMV is spread through contact with bodily fluids," said Albert Park, MD, chief pediatric otolaryngologist/ENT with University of Utah Health. "A lot of times, pregnant women will have small children in daycare or preschool who will get an infection. When they come home and kiss their mom on the lips or share a utensil with mom, she gets an infection."

In addition to saliva, other common ways to transmit CMV include blood, semen, and other bodily fluids. The best way to prevent an infection is to wash hands frequently and avoid as much contact with bodily fluids as possible—which might require women to avoid kissing their children on the lips or sharing utensils.

Birth Defects and More

Like Zika, CMV is known to cause microcephaly and other birth defects, including hearing loss, premature birth, low birth weight, liver problems, seizures, and more. Even for babies who are born looking healthy, problems may arise. "Hearing loss is the most common deficit from CMV," Park said. "Some children are born deaf while others may slowly lose their hearing over several years."

CMV testing can have a huge impact on a child's family. Newborn hearing screening, which has been universally performed since the late 1990s, can help to diagnose hearing loss in children. But the screening does not provide information on the cause of a child's hearing loss. In 2013, Utah became the first state to require CMV testing in any newborn who fails a hearing test. Unfortunately, CMV is not offered in most states—even for those who fail their newborn hearing screen.

By discovering CMV early, the severity of the infection can be determined and treatment can begin immediately. For those with severe infection, antiviral therapy can also begin immediately, which has been shown to improve hearing and brain development. Hearing aids or cochlear implantation can also be offered earlier to optimize speech and language development.

By raising awareness of CMV and its impact on babies, doctors hope to reduce the number of cases discovered each year. Early CMV screening offers the hope to identify more at-risk children. As of now, no vaccines for the illness exist, and CMV cases seem to be more frequent among low-income households. By sharing information about it, more people can take preventive measures and ensure that babies are born healthy.