RT Journal Article SR Electronic T1 Staff–pupil SARS-CoV-2 infection pathways in schools in Wales: a population-level linked data approach JF BMJ Paediatrics Open JO BMJ Paediatrics Open FD BMJ Publishing Group Ltd SP e001049 DO 10.1136/bmjpo-2021-001049 VO 5 IS 1 A1 Daniel A Thompson A1 Hoda Abbasizanjani A1 Richard Fry A1 Emily Marchant A1 Lucy Griffiths A1 Ashley Akbari A1 Joe Hollinghurst A1 Laura North A1 Jane Lyons A1 Fatemeh Torabi A1 Gareth Davies A1 Mike B Gravenor A1 Ronan A Lyons YR 2021 UL http://bmjpaedsopen.bmj.com/content/5/1/e001049.abstract AB Background Better understanding of the role that children and school staff play in the transmission of SARS-CoV-2 is essential to guide policy development on controlling infection while minimising disruption to children’s education and well-being.Methods Our national e-cohort (n=464531) study used anonymised linked data for pupils, staff and associated households linked via educational settings in Wales. We estimated the odds of testing positive for SARS-CoV-2 infection for staff and pupils over the period August– December 2020, dependent on measures of recent exposure to known cases linked to their educational settings.Results The total number of cases in a school was not associated with a subsequent increase in the odds of testing positive (staff OR per case: 0.92, 95% CI 0.85 to 1.00; pupil OR per case: 0.98, 95% CI 0.93 to 1.02). Among pupils, the number of recent cases within the same year group was significantly associated with subsequent increased odds of testing positive (OR per case: 1.12, 95% CI 1.08 to 1.15). These effects were adjusted for a range of demographic covariates, and in particular any known cases within the same household, which had the strongest association with testing positive (staff OR: 39.86, 95% CI 35.01 to 45.38; pupil OR: 9.39, 95% CI 8.94 to 9.88).Conclusions In a national school cohort, the odds of staff testing positive for SARS-CoV-2 infection were not significantly increased in the 14-day period after case detection in the school. However, pupils were found to be at increased odds, following cases appearing within their own year group, where most of their contacts occur. Strong mitigation measures over the whole of the study period may have reduced wider spread within the school environment.Data are available upon reasonable request. The data used in this study are available in the Secure Anonymised Information Linkage (SAIL) Databank at Swansea University, Swansea, UK. All proposals to use SAIL data are subject to review by an independent Information Governance Review Panel (IGRP). Before any data can be accessed, approval must be given by the IGRP. The IGRP gives careful consideration to each project to ensure proper and appropriate use of SAIL data. When access has been approved, it is gained through a privacy-protecting safe haven and remote access system referred to as the SAIL Gateway. SAIL has established an application process to be followed by anyone who would like to access data via SAIL: https://www.saildatabank.com/application-processhttps://www.saildatabank.com/application-process.