Limited transmission of SARS-CoV-2 in schools in Ireland during the 2020-2021 school year

Abstract

BackgroundThe role of schools in SARS-CoV-2 transmission has been a debated topic since the beginning of the COVID-19 pandemic.AimTo examine SARS-CoV-2 transmission in all schools in Ireland during the 2020-21 school year.MethodsIn a national descriptive cross-sectional study, we investigated PCR-confirmed cases of COVID-19 among students (aged < 20 years) and staff (aged ≥ 20 years) who attended school during their infectious period to identify school close contacts. SARS-CoV-2 PCR test results of all school close contacts were pooled to obtain an overall positivity rate and to stratify positivity rate by school setting and role (i.e. student or staff).ResultsIn total, 100,474 individuals were tested as close contacts in 1,771 schools during the 2020-21 school year. An overall close contact positivity rate of 2.4% was observed across all schools (n = 2,373 secondary cases). The highest positivity rate was seen in special schools (3.4%), followed by primary (2.5%) and post-primary schools (1.8%) (p < 0.001). Of the close contacts identified, 90.5% (n = 90,953) were students and 9.5% (n = 9,521) were staff. Overall, students had a significantly higher positivity rate than staff (2.4% vs 1.8%, p < 0.001).ConclusionThis study demonstrated that a low level of SARS-CoV-2 transmission occurred in Irish schools during the 2020-21 academic year. In the event of future pandemics, and as the COVID-19 pandemic continues, there is a need to carefully weigh up the harms and benefits associated with disrupted education to mitigate infectious disease transmission before reflexively closing classes or schools.

Keywords: Epidemiology; Ireland; infection control.

Figure 1

PCR-confirmed COVID-19 cases by age group in Ireland^a, 1 March 2020–10 July 2021^b

Figure 2

PCR-confirmed COVID-19 cases (n = 2,646) associated with reported school outbreaks (n = 601) in all schools in Ireland, August 2020–June 2021