Schools do not need to close to reduce COVID‐19 but other measures are advisable

Abstract

About 1.3 billion students worldwide were affected by school or university closures in April 2020 due to the COVID19 pandemic.1 However, closing schools is controversial. Does it really protect school children, their teachers and families? Or could mitigation measures be as effective as school closures? According to data from the European Centre for Disease Prevention and Control, children and adolescents aged 1– 18 years accounted for 0.13% of the COVID19 deaths in Europe from 1 August to 29 November 2020.2 Therefore, the main aim of disease control in schools is to protect the staff and parents. Two extensive studies have addressed these questions about school closures and mitigation measures. The first was a registered study of the Swedish population.3 Led by economist Jonas Vlachos, it used three national registers to study the occurrence of COVID19 in different groups in Sweden during spring 2020. That was when the country closed upper secondary schools for children aged 17– 19 years in grades 10– 12, but kept lower secondary schools for children aged 14– 16 in grades 7– 9 open. All countries within the European Union and the European Economic Area, except Iceland and Sweden, closed primary schools during part of the pandemic and all closed secondary schools at some point.2 This means that school closures in Sweden could be evaluated by comparing grade 9 children in the open schools and grade 10 children in the closed schools. The comparison showed a small increase in infections amongst the parents of the younger children in the open schools, and double the infection rate in their teachers when they were compared to the teachers of the older children, who were receiving online teaching instead. These infections were spilled over to the teachers partners. Keeping the lower secondary schools open had an impact on the spread of the virus that causes COVID19. Vlachos et al compared 124 occupations, excluding health professionals, and upper secondary teachers were at the median level, whilst lower secondary teachers were the seventhmost affected occupation. However, they were much less affected than people like taxi drivers, police officers and social workers. Up to June 2020, closing all lower secondary schools in Sweden could have saved the lives of five parents and 1.5 teachers and their partners, according to highly uncertain calculations. A large portion of the virus transmissions to teachers was probably from other school staff, not from students. Measures to protect them could be considered. The authors did not recommend closing lower secondary schools. Unfortunately, wearing face masks is not common in Sweden, but mandatory face masks for teachers could be considered. The second study was a massive online survey carried out in the United States.4 Epidemiologist Justin Lessler and his team used data from the ongoing Facebookbased COVID19 Symptom Survey, which is administered by Carnegie Mellon University. It yields approximately 500,000 survey responses a week from the 50 US states and the US capital Washington DC. The researchers found that living in a family with a child attending fulltime, facetoface schooling was associated with a significant increase in the odds of reporting a COVID19like illness (adjusted odds ratio 1.38, 95% confidence ratio 1.30– 1.47). Lessler et al agreed with Vlachos et al3 that the strength of the associations increased as the children got older. Transmission of COVID19like illnesses in children attending open schools parttime, compared to fulltime, was attenuated but still statistically significant. Teachers working in open schools were more likely to report a COVID19like illness than those working at home. The elevated risk was of the same magnitude as health care and office workers. Lessler et al studied 14 schoolbased, lowcost mitigation measures, including three associated with significant reductions in risk: daily symptom screening, mandatory masks for teachers and cancelling extracurricular activities. When seven or more mitigation measures were in place there was no significant difference in the occurrence of a COVID19like illness between children attending school fulltime or studying at home because their school was closed. The findings of these two research groups in Sweden and the USA are supported by other studies.5,6 In spring 2020, Swedish preschool teachers and school teachers had relative risks of 1.10 and 0.43, respectively, of needing intensive care due to COVID19. This was when they were compared with other occupations, excluding healthcare workers.7 The European Centre for Disease Prevention and Control performed a comprehensive search of the relevant literature up to 18 November 2020.2 The review concluded that adults were not at higher risk of the virus that causes COVID19 in school setting than in other settings. Precautionary physical distancing measures should be used when staff interact with adolescents and other adults. It is important to remember that school closures can have detrimental effects on children and society. The children s rights to education are at risk and untold numbers of healthcare workers and other workers have to stay at home to look after their