Abstract
Background: The role of children in the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in schools has been a topic of controversy. We investigated transmission from children in comprehensive school contact-investigations and assessed whether these differed by age of the children and by viral variants.Methods: We prospectively followed school contacts of children with laboratory confirmed SARS-CoV-2 infection in Norway from August 2020 to May 2021. All participants were tested for SARS-CoV-2 twice during the 7–10 days follow-up period, using PCR on home-sampled saliva. Positive samples were whole genome sequenced to determine possible transmission.Findings: In 43 contact-investigations, 559 child contacts were tested, of which eight tested positive (1·4%, 95% CI 0·62–2·80). We found no significant difference between primary (1·0%, 95% CI 0·27–2·53) and secondary schools (2·6%, 95% CI 0·70–6·39), p=0·229, or between the period before (1·4%, 95% CI 0·50–2·94) and after (1·7%, 95% CI 0·21–5·99) the Alpha variant (B.1.1.7) was established in the study area (March 2021), p=0·665. Only one adult contact (1/100, 1·0%) tested positive. In 34 indexes, we detected 13 different SARS-CoV-2 Pango lineage variants with the B.1.1.7 (Alpha) being the most frequent. In the eight contact-investigations with SARS-CoV-2 positive contacts, four had the same SARS-CoV-2 sequence identity as the index, one had no relation, and three were inconclusive. Interpretation: We found limited spread of SARS-CoV-2 from children in schools even after rigorous contact tracing and testing of school contacts, including the more transmissible Alpha variant. Whole genome sequencing revealed high consistency in SARS-CoV-2 Pango lineages, but ruled out transmission in one contact-investigation. By excluding contact-investigations with adult cases known at the time of enrollment, our data provide a valid estimate on the role of children in transmission of SARS-CoV-2 in schools. Funding Information: Norwegian Institute of Public Health.Declaration of Interests: None of the authors declare competing interests.Ethics Approval Statement: The Regional Committees for Medical and Health Research Ethics in Norway approved the study (reference 151649). The study complies with the EU general data protection regulation (GDPR) requirements. Consent was obtained from all participants of 16 years or above, or from both parents for participants <16 years. In case of sole parental responsibility, a single consent was sufficient.
Highlights
(26%) contact investigations were included in the period in which Alpha was dominant
60% (559/935) of child contacts and 63% (100/158) of adult contacts consented to participate in the study
Since we excluded contact investigations with adult cases that were known at the time of enrolment, our data provide a valid estimate on the role of children in transmission of SARS-CoV-2 in schools
Summary
Many countries adopted school closures and strict infection prevention and control measures (IPC) to limit the spread of SARS-CoV-2, based on the assumption that transmission among children may augment the spread of the virus in the wider community. At the outset of this study, little was known about the role of children in SARSCoV-2 transmission in schools, the role of asymptomatic infections [6]. Several contact-investigation studies have been published, including a subset of the data included in this report [7], showing limited transmission in schools when appropriate mitigation measures are in place [5]. Asymptomatic and mild symptoms in children may have led to low case-ascertainment of infections in children, early in the pandemic [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
