CMV Overview

Cytomegalovirus (CMV) is a common viral infection, occurring in more than half of adults at some point in their life. For most healthy people, an infection with CMV may cause no symptoms or mild symptoms. For immunocompromised people, CMV may cause more severe illnesses.

Once a person is infected with CMV, the virus remains dormant in their body for life, similar to a variety of other viruses within the same family. It is possible for the virus to reactivate, though most people won’t feel ill when this happens.

1 in 200 newborns are infected by cCMV each year

Congenital CMV

Congenital CMV occurs when a fetus becomes infected with CMV while still in the womb. It turns out this is the most common infection in newborns, occurring in an estimated 0.5% of all newborns in the United States, or 1 in every 200 babies.

Of those newborns with congenital CMV, the signs, symptoms, and long-term complications of the infection vary widely

10% - 15%

10 - 15% of infected newborns with have symptoms

Studies show that about 10-15% of newborns with congenital CMV will have symptoms of infection at birth, and about half of those babies will develop long-term complications of the infection.

10%

10% of 85-90% of non-symptomatic newborns with develop hearing loss

Of the 85-90% with no symptoms at birth, about 10% will develop hearing loss as the get older. As a result, congenital CMV is the leading infectious cause of childhood hearing loss, and one of the most common causes of hearing loss overall.

Other common complications of congenital CMV include developmental disabilities and impaired vision.

Since these symptoms may not be present at birth, it becomes important to closely monitor children with congenital CMV for the development of hearing loss and developmental disabilities as they age, though most children will have no complications of these infection.

Hearing Loss

Developmental Disabilities

Impaired Vision

Diagnosing cCMV

CMV diagnosis has evolved over time. For decades, only those children with more prominent symptoms of congenital CMV at birth underwent testing for the infection. These symptoms include weighing less or having a smaller head size than expected, having a particular rash, seizures, or having poor muscle tone, among other features.

As a result of identifying only those infants with obvious symptoms, the majority of infants with congenital CMV (who have no symptoms) were not diagnosed.

More recently, some states have developed “targeted” CMV testing programs. These programs generally require that all infants who fail the routine hearing test performed on all newborn babies be tested for CMV. In October, 2018, New York State passed such a law.

Since most babies have normal hearing and no symptoms of congenital CMV at birth, this still leaves many newborns undiagnosed. That has led to interest in “universal congenital CMV newborn screening”.

cCMV Symptoms

Weighing Less
Smaller than Expected Head
Rash
Seizures
Poor Muscle Tone

The NYS Newborn Screen aims to test all newborns for cCMV beginning October 2023

Universal cCMV Newborn Screening

Universal newborn screening for congenital CMV is the process of testing all newborn babies for CMV infection before they leave the hospital. This is typically done by testing a drop of the baby’s blood for the virus. Such testing, called the Newborn Screen, is already performed for dozens of diseases throughout the United States. Few locations in North America currently screen for congenital CMV.

Beginning October, 2023, New York State began a one-year pilot program to test all newborns for congenital CMV. As with other locations, the test is performed on the same sample already collected for the routine Newborn Screen administered by the New York State Department of Health. All infants who screen positive are referred immediately to a designated regional Pediatric Infectious Disease expert who will order lab testing to confirm the diagnosis and perform a thorough evaluation to find any signs of infection. If the baby is confirmed to have congenital CMV, next steps regarding treatment and monitoring are discussed with the infant’s family.

Parents of newborns who screen positive for congenital CMV will be asked to participate in the PROACTIVE NYS study, which will closely follow the growth and development of these infants over the next 2-3 years.