Straight to the point

Data from the SARS outbreak in mainland China, Hong Kong, and Singapore suggest that school transmission played no substantial role in the outbreak, and that school closures and other activities such as school temperature monitoring did not contribute to control of infection transmission. It is possible that these findings reflect an effect of school closures in rapidly stopping transmission; however, this is unlikely as schools remained open for prolonged periods during the early part of the outbreak. Modelling studies from the SARS outbreak produced different results. Although Becker and colleagues estimated that school closure resulted in potentially important reductions in transmission, Liao and colleagues estimated that transmission in school classrooms was low.

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Modelling studies from the COVID-19 pandemic support the use of national school closure as part of a package of social distancing measures. Yet, the only study to examine school closures as a separate intervention warned that the impact was relatively marginal, given the reasonable assumptions that household and community contacts would rise as a consequence.

There are few data available from the literature on coronavirus outbreaks to guide countries on the use of school closures or other school social distancing practices during the COVID-19 pandemic. Available evidence is consistent with a broad range of impacts of school closures, from little effect on reducing transmission through to more substantial effects. Yet, the economic costs and potential harms of school closure are undoubtedly very high.

Source: School closure and management practices during coronavirus outbreaks including COVID-19: a rapid systematic review – The Lancet Child & Adolescent Health