SARS-CoV-2 acquisition and immune pathogenesis among school-aged learners in four diverse schools

Abstract

Background Understanding SARS-CoV-2 infection in children is necessary to reopen schools safely. Methods We measured SARS-CoV-2 infection in 320 learners [10.5 ± 2.1 (sd); 7–17 y.o.] at four diverse schools with either remote or on-site learning. Schools A and B served low-income Hispanic learners; school C served many special-needs learners, and all provided predominantly remote instruction. School D served middle- and upper-income learners, with predominantly on-site instruction. Testing occurred in the fall (2020), and 6–8 weeks later during the fall-winter surge (notable for a tenfold increase in COVID-19 cases). Immune responses and mitigation fidelity were also measured. Results We found SARS-CoV-2 infections in 17 learners only during the surge. School A (97% remote learners) had the highest infection (10/70, 14.3%, p < 0.01) and IgG positivity rates (13/66, 19.7%). School D (93% on-site learners) had the lowest infection and IgG positivity rates (1/63, 1.6%). Mitigation compliance [physical distancing (mean 87.4%) and face-covering (91.3%)] was remarkably high at all schools. Documented SARS-CoV-2-infected learners had neutralizing antibodies (94.7%), robust IFN-γ + T cell responses, and reduced monocytes. Conclusions Schools can implement successful mitigation strategies across a wide range of student diversity. Despite asymptomatic to mild SARS-CoV-2 infection, children generate robust humoral and cellular immune responses. Impact Successful COVID-19 mitigation was implemented across a diverse range of schools. School-associated SARS-CoV-2 infections reflect regional rates rather than remote or on-site learning. Seropositive school-aged children with asymptomatic to mild SARS-CoV-2 infections generate robust humoral and cellular immunity.

Assessing Seroprevalence of SARS-CoV-2 Antibodies Among US College Students after School Reopening

“…80 It has been shown that schools with multi-layered precautions and/or mask mandates have been more successful at limiting SARS-CoV-2 spread in classes and/or campuses and limiting outbreaks. 81–83 Nevertheless, even though observations have been somewhat reassuring regarding a similar level of transmission in schools as in the community, some demonstrating even lower rates in children enrolled in on-site classes, 24, 84, 85 several reports point to increases in county-level COVID-19 incidence following outbreaks at colleges with in-person instructional formats, 86, 87 perhaps also indicative of differences between K-12 schools and higher educational settings. Further, during the period of our study COVID-19 vaccines were not yet authorized.…”

Research progress in spike mutations of SARS‐CoV‐2 variants and vaccine development

“…In addition, the risk of severe disease or death is relatively low in hospitalized patients with Omicron. In Canada, Omicron infected cases have a 65% lower risk of hospitalization or death than Delta infections 59 . In vitro studies revealed that Omicron replicated faster than Alpha, Beta, and Delta 60 .…”

“…In Canada, Omicron infected cases have a 65% lower risk of hospitalization or death than Delta infections. 59 In vitro studies revealed that Omicron replicated faster than Alpha, Beta, and Delta. 60 Interestingly, the replication competence of Omicron in human alveolar cells was significantly lower than that of Delta, 60 which might explain the reduced severity of Omicron.…”