SARS-CoV-2 Acquisition and Immune Pathogenesis Among School-Aged Learners in Four K-12 Schools

Cooper, D. M.; Messaoudi, i. R.; Aizik, S.; Camplain, R. L.; Lopez, N. V.; Ardo, J.; Boden-Albala, B.; Chau, C.; Condon, C.; Golden, C.; Coimbra Ibraim, I.; Jankeel, A.; Kasper, K.; Meyer, A.; Stehli, A.; Stephens, D.; Weiss, M.; Zulu, M. Z.; Ulloa, E. R.

Objectives. To directly measure SARS-CoV-2 infection in diverse schools with either remote or onsite learning. Methods. 4 schools participated. Schools A and B served low-income Hispanic learners, school C special needs, and all three provided predominantly remote instruction. School D served middle and upper-middle income, White learners, with predominantly onsite instruction. 320 learners [10.5+/-2.1(SD); 7-17 y.o.]; 86% had phlebotomy. Testing occurred early in the fall (2020), at lower levels of COVID-19, and 6-8 weeks later during the fall-winter surge (tenfold increase in COVID-19 cases). Results: Nasal RT-qPCR for SARS-CoV-2 and 21 respiratory pathogens was performed. Phlebotomy was obtained for circulating immunity. Face covering and physical distancing fidelity was measured by direct observation. 17 learners were SARS-CoV-2 positive during the surge. School A (97% remote) had the highest infection rate (9/70, 12.9%, p<0.01) and IgG positivity rate (13/70, 18.6%). School D had the lowest infection and IgG positive rate (1/86, 1.2%). Mitigation compliance [physical distancing (mean 87.4%) and face covering (91.3%)] was high at all schools. Learners with documented SARS-CoV-2 infection had neutralizing antibodies (94.7%), broad and robust interferon-gamma T cell responses, reduced frequencies of monocytes, and lower levels of circulating inflammatory mediators. Conclusions: Infection in the schools reflected regional rates rather than remote or onsite learning modalities. Schools can implement successful mitigation strategies across a wide range of income, school-type, and student diversity. Reduced monocyte and immune mediator concentrations coupled with robust humoral and cellular immunity may explain the generally milder symptoms in school-aged children.