584 - Out of home child care as a risk factor for pre-pandemic endemic human coronavirus infections in a birth cohort of children 0-2 years

Poster Number: 584
Publication Number: 584.417

Ardythe L. Morrow, University of Cincinnati College of Medicine, Cincinnati, OH, United States; Shannon C. Conrey, University of Cincinnati College of Medicine, CINCINNATI, OH, United States; Liang Niu, University of Cincinnati College of Medicine, Cincinnati, OH, United States; Allison R. Burrell, University of Cincinnati College of Medicine, Cincinnati, OH, United States; Claire Mattison, United States Centers for Disease Control and Prevention, Atlanta, GA, United States; Zheyi Teoh, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Meredith McMorrow, CDC, Atlanta, GA, United States; Monica M. McNeal, OH, Cincinnati, OH, United States; Daniel C. Payne, CDC, Atlanta, GA, United States; Mary A. Staat, CCHMC, Cincinnati, OH, United States

Background: Four endemic human coronaviruses (HCoV; HKU1, OC43, 220E, NL63) belong to the same viral subfamily as SARSCoV2 and routinely circulate worldwide, but typically cause only mild illness.

Objective: Studying endemic HCoV in relation to out of home child care (OOHC) provides a general epidemiological model of coronavirus transmission.

Design/Methods: We analyzed HCoV infection rates, symptoms, and risk factors for infection in a subset of children enrolled in PREVAIL, a CDC-funded birth cohort study in Cincinnati, OH from 4/2017-8/2020. Enrolled children were followed from birth to age 2. Weekly, study mothers responded to SMS text surveys about their child’s symptoms and collected mid-turbinate nasal swabs from their child. Swabs were tested for HCoV using the Luminex Respiratory Pathogen Panel. Subjects included in these analyses provided samples in >70% of study weeks.

Results: Of 101 children who met inclusion criteria, 162 HCoV infections were documented in 80 (79%) children. The most commonly identified HCoV was OC43 (58 inf.), followed by HKU1 (49 inf.) and NL63 (46 inf.), with a median age at first HCoV infection of 8.3 months. Most HCoV infections were asymptomatic (n=108, 67% and only 23 (14%) infections were medically attended; none resulted in hospitalization. More than 60% of mothers reported OOHC use at 6 weeks of age. Use of OOHC was evenly split between childcare homes (providers care for small groups of children in a residential building) and licensed childcare centers until 12 months of age; however, 2/3 of children were enrolled in a center by 18 months of age. As expected, peer group size was larger in centers (median=9/group) than childcare homes (median=4/group; p < 0.001). In a generalized Cox survival model, periods of OOHC were associated with increased infection risk (childcare home: relative risk [RR] 1.6; 95% CI 1.1, 2.1; p=0.05; center: RR 3.0; 95% CI 2.5, 3.4 p < 0.001). Male children were at increased risk of HCoV infection (RR=1.6; 95% CI 1.2, 2.0; p=0.03), but household size, breastfeeding, and maternal demographics were not significantly associated with risk of infection. Among those infected, OOHC use did not influence risk of respiratory symptoms, but male children were 3.2 times more likely to have acute respiratory symptoms than female children (p=0.008).Conclusion(s): In the PREVAIL Cohort, the high frequency of HCoV infection indicates that young children, particularly those in center-based OOHC, may play an important role in community transmission of HCoV. These findings may be relevant to efforts to minimize transmission of coronaviruses.