541 - A Significant Reduction in Congenital Cytomegalovirus (cCMV) Prevalence Has Been Observed During the COVID-19 Pandemic: Demographic Data from a Universal cCMV Screening Study, Minnesota, 2016–2021

Poster Number: 541
Publication Number: 541.328

Mark R. Schleiss, University of Minnesota Medical School, Division of Ped Inf Dis, Minneapolis, MN, United States; Erin A. Osterholm, University of Minnesota Masonic Children's Hospital, Minneapolis, MN, United States; Nelmary Hernandez-Alvarado, University of Minnesota Medical School, Minneapolis, MN, United States; Sondra Rosendahl, Minnesota Department of Health, St. Paul, MN, United States; Mark McCann, MDH, Saint Paul, MN, United States; Abbey Sidebottom, Allina Health, Minneapolis, MN, United States; Rebecca Kruc, University of Minnesota Medical School, Fridley, MN, United States; Hannah Herd, University of Minnesota Masonic Children's Hospital, Minneapolis, MN, United States; Kristin E. Gravel, Midwest ENT Specialists, Lauderdale, MN, United States; Sheila Dollard, CDC, 1600 Clifton Rd, GA, United States; Tatiana M. Lanzieri, Centers for Disease Control and Prevention, Atlanta, GA, United States

Background: Congenital CMV (cCMV), with an estimated prevalence of 4.5 per 1,000 live births, is the most common viral infection causing disabilities in US children. In 2016, we established a study to determine optimal diagnostic strategies for universal cCMV screening, and to evaluate infant outcomes. Enrollment was temporarily halted at the onset of the COVID-19 pandemic in March, 2020 and resumed in August, 2020.

Objective: To describe the demographics of cCMV infection in a universal screening study in Minnesota, and to compare the prevalence of cCMV before and during the COVID-19 pandemic.

Design/Methods: In six Twin Cities hospitals, consented infants were tested for cCMV using saliva collected 1-2 days after birth, and dried blood spots obtained for routine newborn screening. Screen-positive infants with confirmatory urine PCR testing by 3 weeks of age underwent diagnostic evaluation. Using international consensus criteria, cCMV cases were classified as: 1) moderately-to-severely symptomatic; 2) mildly symptomatic; 3) asymptomatic with isolated sensorineural hearing loss (SNHL); and 4) asymptomatic.

Results: In total, 19,017 newborns were screened and 76 (4.0 per 1,000) cCMV cases identified. A total of 15,697 infants were screened pre-pandemic, with 70 cCMV cases confirmed (4.5 per 1,000). During the pandemic, 3,320 infants have been screened, with 6 cCMV cases identified (1.8 per 1,000; p=0.02). Among 76 infants with cCMV, 62 (82%; 4.8 per 1,000) were born to non-Hispanic white women and 9 (12%; 5.4 per 1,000) to non-Hispanic Black women (p=0.99). Twenty-seven (36%) infants with cCMV were first-born. All 49 (64%) of the infants with cCMV born to multiparous mothers had a sibling in daycare. Prevalence was higher among second-born than first-born infants (Table 1; 6.3 vs. 3.3 per 1,000; prevalence ratio 1.9; p=0.01). Among 76 cCMV cases, 5 were moderately-to-severely symptomatic; 8 mildly symptomatic; 3 asymptomatic with SNHL; and 60 asymptomatic. Nine of 76 cases (11.8%) were diagnosed with congenital or delayed-onset SNHL.Conclusion(s): In this cohort, parity impacted cCMV prevalence, particularly for women with children in group daycare. White and Black infants had comparable prevalence. The prevalence of cCMV decreased significantly during the COVID-19 pandemic, compatible with reduced daycare utilization, and behavioral changes and mitigation measures in childcare facilities (e.g., smaller class sizes, increased hand hygiene, and disinfection) aimed at reducing SARS-CoV-2 transmission. These findings might help inform future cCMV prevention strategies focused on hygiene promotion and behavioral change.
Table 1. Demographics of cCMV infection a cohort of Minnesota newborns, 2016-2021.Parity and pandemic: two key factors impacting the prevalence of cCMV in a universal screening study in Minnesota. A significant correlation between birth order and cCMV is noted, and a substantial reduction in cCMV infection prevalence observed during the COVID-19 pandemic was also statistically significant.