The role of school settings in COVID-19 transmission

While neither Sweden nor Iceland closed their preschools or primary schools at any stage during the COVID-19 pandemic, and Denmark reopened childcare and primary education as early as 15 April, many European countries continued with remote learning arrangements until the summer break. Now these countries are sending children back to school.

The measures planned differ between — and even within — countries. Germany, for example, has 16 federal states, each with its own Ministry of Education. The recommendation on the use of masks — who should wear them and where they should do so in school (in classrooms only or everywhere on the school premises and in the grounds) depends on the strategy of each individual country or state, in spite of the fact that the World Health Organization (WHO) recommends the use of masks from the age of six onwards.

Susanne Kuger, head of the Department of Social Monitoring and Methodology, German Youth Institute: “We are currently trying to research the number of settings that actually closed as a result of coronavirus in the last few months [less than 1% in most weeks since May], which is not that easy because, as you might know, Germany doesn’t have one education system, but 16. This means we have 16 different ministries and 16 different types of official statistics to try to harmonise and look through.” – Read the full interview Susanne Kuger

The contingency plans, like the countries’ strategies for facing up to the pandemic, also might differ quite considerably. During the first phase of the re-opening, some schools closed as soon as they detected a positive case, regardless of whether the person affected was a student or a staff member. ‘[But] closing the schools should be really the last measure that you take,’ Andrea Ammon, head of the European Centre for Disease Prevention and Control (ECDC), told EU lawmakers in the European Parliament’s Committee on the Environment, Public Health and Food Safety (ENVI).

In Germany, as soon as a new case is detected in a school setting, all the contacts at the school or at home are tested: those who test negative can return to classes, while the others are told to quarantine. In Sweden, on the other hand, in spite of the outbreaks that led to some school closures and the death of staff members from COVID-19, as of May the public health authorities were not testing children at school, did not feel that contact tracing was that important and only tested individuals showing symptoms.

In general, the Swedish Public Health Agency is assuming in the fourth and current version of its strategy that, during the pandemic phase – when there is a wide community spread of the virus contact tracing and testing do not make much sense as the transmission chains seem difficult to control anyway. Therefore, some groups were prioritised for testing, students, teachers or school staff were not.

On the last day of August, the Swedish authority released a new guideline on testing for COVID-19 among children and teenagers, as no national guideline existed and decisions were being taken at regional and local level. The recommendation is that children and teenagers should be tested if they present COVID-19 symptoms, but children of preschool age should only be tested if there is a growing number of cases in their area. No recommendation has been issued on contact tracing.

Lisa Ferland, Infectious Disease Expert at the ECDC: “There are numerous limitations to the current evidence that include, but are not limited to, the unknown proportion of mild and asymptomatic cases in children, case-based surveillance limitations for identifying outbreaks in schools, limited information on testing strategies in school settings, and difficulty detecting ongoing transmission in the school setting versus in the community or household.” – Read the full interview Lisa Ferland

The role of school settings in COVID-19 transmission

School closures in March led to a ‘steep decline in infectious diseases more generally [in German school settings],’ says Susanne Kuger, speaking about colds and other viruses common in children. Nevertheless, and specifically in relation to SARS-CoV-2, the report from the ECDC concluded that ‘closures of childcare and educational institutions are unlikely to be an effective single control measure for community transmission of COVID-19’.

The ECDC also concluded that the ‘re-opening schools has not been associated with significant increases in community transmission’. And a Public Health Authority study in Sweden has shown that teachers were at no higher risk of COVID-19 than other occupational groups.

Children, teachers and other staff members in school settings might not be taking the virus home from schools, but the opposite — from the community into schools — seems to be true. One week after their re-opening in May, France witnessed 70 cases of COVID-19 in primary and nursery schools, but most of them ‘happened outside of the school,’ said Jean-Michel Blanquer, France’s education minister, in an interview with RTL radio. On 3 September, 12 schools that had started the new academic year were closed.

In Spain, where all school settings have been closed since March, the Sant Joan de Déu Barcelona Children’s Hospital has been studying children and adults taking part in summer camps, collecting samples from 1 905 participants. The research project identified a total of 39 index cases. The 30 paediatric cases came into contact with 253 children in their bubble groups, 12 of which were infected. The project team concluded in a press release that ‘This rate is almost six times lower than that of the general population at the time of the study in the areas where the camps were held’. These are still preliminary results, but the team wanted to present them before the beginning of the new school year.

Susanne Kuger: “Even though the ratio of children with COVID-19 symptoms and infections is going up, in terms of their share of the number of infected people as a whole, we don’t see any reason to believe that this is owing to childcare [facilities] because, typically, children’s source of infection is their parents.”

The Spanish results are in line with the WHO’s conclusions: ‘So far we know that the school setting has been not a main contributor to the epidemic,’ Hans Kluge, WHO regional director for Europe, told in a news briefing. He added that children’s role in the transmission of the virus ‘is so far more linked with social gatherings’.

Bubbles, hand washing and staying home if sick

In spite of the recommendations, the WHO acknowledges that it is hard for children to comply with face mask and social distancing rules, so countries are implementing their own strategies that may not involve such measures.

Iceland and the Netherlands did not recommend physical distancing among children, only adults. Denmark split school classes up into smaller groups. But not every country or school has enough teachers or rooms to split the students up into smaller groups, so some countries, like the UK, are planning to use ‘protective bubbles’ — each child interacts with the others belonging to their bubble, but not with those outside of it.

Lisa Ferland: “It is recognised that physical distancing is challenging for the younger age groups, for those under the age of 12, in the preschools and in primary school settings. There is currently limited data to assess the risk of infection comparing schools that implement mandatory physical distancing with those that do not.”

In the Catalonian summer camps that were studied, bubbles were ‘an effective way of containing the transmission of the infection, facilitating the traceability of contacts and allowing selective quarantine,’ stated Iolanda Jordan, the study’s principal investigator, in a press release. But the study also highlighted the importance of hand washing correctly, which has been associated with a decrease in disease transmission.

Other strategies are also being implemented. Serbia has a combined model, with children attending online classes and taking part in distance learning, but also going to school every other week. Romania plans to implement traffic light zones depending on the number of infections per thousand residents in the area. This means that Romanian schools either function normally (green), children may only attend some courses (yellow), or they might have to continue home schooling (red).

Sweden did not implement very strict measures during the pandemic, even when the schools remained open, but had one very important recommendation: everyone with mild symptoms should stay at home.

Susanne Kuger: “From what we have learned so far, the most important measures are actually to open up the windows at least once an hour. This also means going outside as much as you possibly can.”

The risk of not going to school

“Fewer than 5 % of COVID-19 cases reported in EU/EEA countries and the UK have been in persons under 18 years of age”, the ECDC reports. This means that the ECDC, the WHO, UNESCO and UNICEF agree that closing schools does not reduce the risk of children becoming infected with SARS-CoV-2 — nor does it reduce the transmission rate in the community.

On the other hand, closing schools has a greater impact on children’s health, well-being and security, especially among children from vulnerable and marginalised population groups.

Apart from being deprived of learning opportunities (as many children face difficulties related to home schooling), children may face poor nutrition because they lack school meals; economic losses because parents cannot go to work as they have to take care of them; increased exposure to domestic and sexual violence; and social isolation that may lead to anxiety and depression, as UNESCO has pointed out.

Useful link:
• WHO Q&A