Congenital Cytomegalovirus Testing Following Pennsylvania Hearing-Targeted Screening Legislation

Abstract

BACKGROUND: Congenital cytomegalovirus infection (cCMV) occurs in approximately 1/200 to 1/250 US newborns each year and can cause progressive sensorineural hearing loss. Since 2022, Pennsylvania law mandates cCMV testing for infants who fail newborn hearing screening. OBJECTIVES: To assess changes in cCMV testing rates and diagnosis before and after Pennsylvania hearing-targeted legislation. METHODS: Retrospective cohort study of all live births at 3 university-affiliated birth centers. We identified all infants tested for CMV at 21 days of age or younger and analyzed cCMV testing rates in pre- (January 2018-June 2022) and post- (July 2022-December 2024) legislation eras using interrupted time-series analysis. We assessed other clinical signs associated with cCMV testing using standard statistics. RESULTS: The study cohort included 85 324 infants. Among 54 909 born prelegislation, 3168 (5.8%) had cCMV testing; among 30 415 born postlegislation, 3197 (10.5%) were tested. cCMV testing rates increased significantly among term (by 3.2%) and preterm infants (by 15.5%) at the beginning of the postlegislation era (P = .003 and .001, respectively). Among 5224 infants with hearing-based criteria for screening, CMV testing increased from 36.7% prelegislation to 74.0% postlegislation (P < .001). In the postlegislation period, testing associated with isolated microcephaly increased, but isolated small for gestational age-associated testing decreased. Among 61 infants diagnosed with cCMV, 16 (26.2%) were identified based on hearing criteria alone (2.3/1000 infants prelegislation, 6.0/1000 infants postlegislation, P = .04). CONCLUSIONS: CMV testing and diagnosis based on hearing criteria alone increased significantly post passage of Pennsylvania hearing-targeted cCMV testing legislation, but infants tested for hearing criteria alone accounted for less than half of identified cCMV cases.