Case study suggests kindergartens are not SARS-CoV-2 super-spreaders

By Angela Betsaida B. Laguipo, BSNDec 11 2020

As coronavirus disease 2019 (COVID-19) continues to spread across the globe, scientists have raced to understand better the virus and how it affects people.

Caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pathogen, the disease can cause mild to severe symptoms. Some people are at a higher risk of developing severe COVID-19, including the elderly and those with underlying health conditions.

Children and young people typically develop mild symptoms to no symptoms at all. However, they have been deemed super-spreaders since they are thought to transmit to others without knowing they are infected.

A new study by researchers at the Institute of Tropical Medicine and International Health at the Charite Universitaetsmedizin Berlin found that kindergartens are not silent transmission reservoirs. Nevertheless, they recommend that reinforced precautionary measures and routine testing are still essential to reduce SARS-CoV-2 transmission.

It is critical that measures to contain the SARS-CoV-2 pandemic be implemented, particularly in kindergartens and schools. Since schools have re-opened in many parts of the world, debates about whether children act as super-spreaders have emerged. However, actual data on infection prevalence and transmission in such facilities are rare.

Study: SARS-CoV-2 infections in kindergartens and associated households at the start of the second wave in Berlin, Germany – a cross sectional study. Image Credit: FamVeld / Shutterstock

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources

The study

The study, published in the pre-print journal medRxiv*, aimed to assess the prevalence of SARS-CoV-2 infections and immunoglobulin G (IgG) seroreactivity among pre-school children and household members connected with Berlin kindergartens during the beginning of the second pandemic wave.

To arrive at the study findings, the researchers visited 12 Berlin kindergartens between September 29 and October 2. About 1,561 polymerase chain reaction (PCR) confirmed SARS-CoV-2 infections were reported in the area within the week.

In each kindergarten, the team aimed to recruit 20 children and five staff members, whenever possible. A total of 720 individuals participated in the study.

The researchers visited each facility to collect samples and data. All the children and staff were interviewed on signs and symptoms. The team also measured the participants' forehead temperature.  

Further, the team collected nasopharyngeal swabs. Household members who picked up the children were also invited to participate. They were instructed to bring their self-collected swabs, which were given beforehand. For the seroreactivity test, finger-prick blood samples were collected on filter paper.

What the study found

The researchers found that the signs and symptoms present in one in four kindergarten children include runny nose, cough, and sore throat. The leading complaints among educators who were sick were a headache, runny nose, and cough.

Further, 2.6 percent of children and 1.3 percent of educators had a fever. Most kindergarten children reportedly never wore a facemask, with higher use rates among staff and household members.

In terms of the schools' infection control measures, two-thirds of the facilities had a physical distance rule between staff and 91.7 percent between staff and parents. Staff was also mandated to wear face masks when interacting with parents and co-workers.

Also, 75 percent of daycare centers allowed children to attend even if they had common cold symptoms. In most facilities, children were taken care of in fixed groups and rooms, which were ventilated more than five times a day.

The study findings also showed that signs and symptoms, mainly resembling common old, were present in 24.2 percent of children and 28.9 percent of staff. But, there was no SARS-CoV-2 infection detected among the 701 tested participants. Only one childcare worker showed IgG seroreactivity.

The team concluded that despite the increasing pandemic activity, kindergarten children are not silent transmission reservoirs of SARS-CoV-2. But the team also noted that infection control measures must still be implemented in schools to ensure no outbreak will occur.

"Rapid response to detected cases, including subsequent contact tracing and quarantine, is essential," the team suggested.

"Recent modeling data suggest that repeated screening, e.g., twice per week, combined with instant reporting, isolation, or quarantine, can greatly reduce viral transmission in a population," they added.

Aside from testing, regular screening with antigen tests is also crucial in kindergarten settings.

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources