Health Advice



Cytomegalovirus lies dormant in most US adults and is the leading infectious cause of birth defects, but few have heard of it

Laura Gibson, Associate Professor of Medicine and of Pediatrics, UMass Chan Medical School, The Conversation on

Published in Health & Fitness

In general, valacyclovir does not work as well as other CMV drugs that people cannot take during pregnancy. As a result, a much higher dose is required to reduce the risk of fetal CMV infection, which may cause significant side effects for pregnant people.

Although the use of valacyclovir to prevent cCMV is not standard in the U.S., and research on its effectiveness remains limited, the drug is used for this purpose in some areas of the world.

Like pregnant people, babies are screened for many potentially serious conditions. An accurate CMV test for newborns is available, and many studies support the benefit of early CMV diagnosis. So why isn’t there universal CMV screening for infants?

While some birth centers provide early CMV testing, most U.S. states do not mandate newborn CMV screening. My team and I surveyed 33 hospitals in Massachusetts from late 2020 to early 2021 and found that less than half are consistently screening infants for cCMV infection. Of those, only a few have a written testing protocol. Only two hospitals performed cCMV screening on all infants admitted to the newborn nursery.

Standardizing public health education and CMV screening guidelines could help reduce the incidence and burden of cCMV disease on children and their families. In July 2013, Utah became the first state to pass legislation mandating a CMV public education program and testing for infants who do not pass the newborn hearing screen. In February 2022, Minnesota became the first – and remains the only – state to require CMV screening of all newborns, although Massachusetts and Indiana have pending universal screening bills. So far, 17 states have enacted laws requiring cCMV education or targeted screening of newborns who meet certain criteria, and many others are considering similar options.

On the other hand, designing, funding and implementing a new infant screening program is complex and time-consuming, and may potentially divert resources from other equally important health initiatives. Most newborns with cCMV appear physically normal at birth and develop normally over their lifetime, leading some to question the benefits of CMV screening for those children.

However, infants may have abnormalities that are not visible at birth, and there isn’t a reliable way to predict whether they will have progressive health problems. Without screening all newborns for CMV, those who appear normal at birth will not be fully evaluated, considered for treatment or monitored for effects that develop later, such as hearing loss.

Decreasing the incidence of cCMV infection is unlikely without increasing awareness. Most people have not heard of CMV or are unwaware of what they can do to reduce their chances of getting CMV during pregnancy.


Many adults are repeatedly exposed to one of the major risk factors for CMV infection: a young child who regularly attends large-group child care. Infections like CMV spread easily among children in settings where group play, meals and diaper changes become daily opportunities for transmission. Children can appear quite healthy but carry CMV in their saliva and urine for weeks or even months after infection. When an unsuspecting pregnant caretaker comes into contact with those body fluids, they can become infected as well.

For people who are pregnant, simple behavior changes such as kissing a child on the head instead of the lips, not sharing food or utensils, and frequent handwashing can significantly reduce the risk of getting CMV.

Educating the public, policymakers and health care providers will improve the diagnosis, prevention and treatment of cCMV, so no parent suffers the thought “If I had only known…”

This article is republished from The Conversation, an independent nonprofit news site dedicated to sharing ideas from academic experts. The Conversation is trustworthy news from experts, from an independent nonprofit. Try our free newsletters.

Read more:
Chickenpox and shingles virus lying dormant in your neurons can reactivate and increase your risk of stroke – new research identified a potential culprit

Pregnancy is a genetic battlefield – how conflicts of interest pit mom’s and dad’s genes against each other

Laura Gibson is a member of the Scientific Advisory Board for the CMV Program at Moderna Therapeutics, Inc. She also receives research funding from Moderna. She is affiliated with the Massachusetts Congenital CMV Coalition.


blog comments powered by Disqus