Jonathan Crews, MD, MS, Pediatric Infectious Diseases, Baylor College of Medicine, The Children’s Hospital of San Antonio
Cytomegalovirus (CMV) is the most common viral cause of birth defects in the United States. About one out of every 200 babies is born with a CMV infection – when this happens, we call it “congenital CMV.” About four out of five babies born with congenital CMV are born healthy without any signs of disease (asymptomatic congenital CMV). About one out of five babies will have birth defects or other long-term health problems (symptomatic congenital CMV).
Babies with congenital CMV that are sick at birth can have a small head size (microcephaly), seizures, rash, lung disease, or a large liver and spleen (hepatosplenomegaly). Hearing loss can occur. Some babies born with asymptomatic congenital CMV can still have or develop hearing loss. Congenital CMV is the leading non-genetic cause of hearing loss in newborns in the US.
Testing can be done from a baby’s saliva, urine, or blood within two to three weeks after birth to confirm congenital CMV. Babies with signs congenital CMV should be tested. Testing should be done on all babies diagnosed with hearing loss. Babies with symptomatic congenital CMV can benefit from antiviral medicines. These medicines can lessen the severity of the hearing loss and long-term health problems, but require close monitoring with a physician due to potential side effects.
CMV is transmitted through body fluids, including urine and saliva. Pregnant women who have or work with young children (especially those in group daycare settings) are at risk of getting the infection. There are several things you can do to help prevent getting CMV during pregnancy. Wash your hands regularly – especially before and after feeding children; and before and after changing diapers. Avoid sharing food, utensils, drinks, or straws. Do not share a toothbrush or put a pacifier in your mouth.
Although CMV is common and serious, many people do not know about it. To learn more about congenital CMV, visit these websites:
Centers for Disease Control and Prevention (https://www.cdc.gov/cmv/)
National CMV Foundation (https://www.nationalcmv.org/)
Congenital CMV Foundation (http://congenitalcmv.org/)
National Congenital CMV Disease Registry (https://www.bcm.edu/departments/pediatrics/sections-divisions-centers/cmvregistry)
If you are concerned about your baby having congenital CMV, talk to your pediatrician. If you need to identify a pediatrician for your baby, please visit www.chofsa.org/findadoc.