Universal Newborn Screening for Congenital Cytomegalovirus Using Dried Blood Spot Specimens.

Importance: Congenital cytomegalovirus (cCMV) is the most common nongenetic cause of sensorineural hearing loss in children and a cause of long-term neurological disabilities. In the absence of universal screening, cCMV disease in many newborns will go undiagnosed and untreated. Objective: To determine the feasibility, screen-positive rate, and parental acceptance of newborn screening for cCMV using dried blood spot (DBS) specimens. Design, Setting, and Participants: In this population-based diagnostic study, newborns whose DBS specimens were submitted to the New York State Newborn Screening Program from October 2, 2023, through September 30, 2024, for routine screening were also screened for CMV. Parents were given the option to opt out of receiving CMV results. Infectious disease specialists at designated medical centers performed follow-up of referred newborns. Of the 208 322 newborns whose specimens were submitted, 245 (0.1%) were opted out of the CMV screen by their parents; 22 families did so after CMV results were released. Exposure: DBS screening of newborns. Main Outcomes and Measures: CMV was detected in DBS specimens from newborns using a quantitative polymerase chain reaction analysis. Appropriate follow-up and treatment were provided to referred newborns. Results: Of the 208 099 newborns (48.6% female and 51.0% male; mean [SD] age at specimen collection, 3.5 [12.3] days [median, 1.0 days]) whose CMV results were reported, 529 had positive CMV screen results (0.3%). Following referral and initial diagnostic evaluation, 276 of the 529 newborns (52.2%) were diagnosed with cCMV (overall rate of 0.1%). Among the 276 newborns with cCMV, 68 (24.6%) had symptomatic cCMV disease, 197 (71.4%) had asymptomatic infection, and 11 (4.0%) had isolated sensorineural hearing loss. Additionally, 131 of the 529 referred newborns (24.8%) had likely acquired CMV postnatally, 17 (3.2%) had false-positive screen results, 43 (8.1%) had unknown CMV classification, and 62 (11.7%) were lost to follow-up or their parents declined follow-up. Of the 68 newborns with symptomatic cCMV disease, 48 (70.6%) were treated with antiviral medication. Conclusions and Relevance: In this diagnostic study, early identification of cCMV allowed newborns to be evaluated, which provided an opportunity for improved outcomes. Although the intent of the screening was to detect cCMV, a sizeable minority of cases identified had postnatally acquired CMV infections. Further studies that incorporate long-term data are needed to better understand the impact of cCMV identification among newborns with asymptomatic infection.