Prevalence of RT-qPCR-detected SARS-CoV-2 infection at schools: First results from the Austrian School-SARS-CoV-2 prospective cohort study

Abstract Background The role of schools in the SARS-CoV-2 pandemic is much debated. We aimed to quantify reliably the prevalence of SARS-CoV-2 infections at schools detected with reverse-transcription quantitative polymerase-chain-reaction (RT-qPCR). Methods This nationwide prospective cohort study monitors a representative sample of pupils (grade 1–8) and teachers at Austrian schools throughout the school year 2020/2021. We repeatedly test participants for SARS-CoV-2 infection using a gargling solution and RT-qPCR. We herein report on the first two rounds of examinations. We used mixed-effects logistic regression to estimate odds ratios and robust 95% confidence intervals (95% CI). Findings We analysed data on 10,734 participants from 245 schools (9465 pupils, 1269 teachers). Prevalence of SARS-CoV-2 infection increased from 0·39% at round 1 (95% CI 028–0·55%, 28 September-22 October 2020) to 1·39% at round 2 (95% CI 1·04–1·85%, 10–16 November). Odds ratios for SARS-CoV-2 infection were 2·26 (95% CI 1·25–4·12, P = 0·007) in regions with >500 vs. ≤500 inhabitants/km2, 1·67 (95% CI 1·42–1·97, P Interpretation This monitoring study in Austrian schools revealed SARS-CoV-2 infection in 0·39%-1·39% of participants and identified associations of regional community incidence and social deprivation with higher prevalence. Funding BMBWF Austria.