Cytomegalovirus in pituitary gland tissue magnified 500x. Photo credit: CDC.
In October 2023, the New York State Newborn Screening Program launched a landmark one-year pilot study to screen every infant born in the state for congenital cytomegalovirus (cCMV). The results of this study, funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, were recently published in JAMA Network Open, confirming the feasibility of using dried blood spots for large-scale cCMV screening. While cytomegalovirus is common and often harmless in most people, infection in utero can lead to severe complications. It is the leading cause of nonhereditary childhood hearing loss and can result in microcephaly, visual impairment, and seizures.
The program utilized quantitative polymerase chain reaction (qPCR) to analyze dried blood spots from approximately 208,000 newborns. The screening identified several key data points regarding the prevalence of CMV infection and treatment for cCMV:
- Screening Results: 529 newborns (1 in 393) screened positive and were referred for specialty care.
- Confirmed Diagnoses: 276 infants were confirmed to have cCMV (1 in 755).
- Clinical Presentation: Among the confirmed cCMV cases, 24.6% were symptomatic, 71.4% were asymptomatic, and 4.0% presented with isolated hearing loss.
- Treatment: Notably, 70.6% of symptomatic infants received antiviral medication. Many were treated as a direct result of early detection by newborn screening.
The study successfully demonstrated that universal screening allows families to access subspecialists early, which could lead to improved developmental and hearing outcomes. However, the pilot also identified challenges to implementation of universal cCMV screening, including the high frequency of detecting postnatally-acquired CMV (which is less severe than congenital infection), false-positive and false-negative results, and the complexities of managing long-term follow-up for infants who are asymptomatic at birth but may be at risk for later-onset developmental issues or hearing loss.