24.12.2021 Based on the existing body of evidence from March 2020 to present, the predominant finding is that children (particularly young children) are at very low risk of acquiring SARS-CoV-2 infection in the first place (limited ACE 2 receptors in the nasopharynx of children (Patel and Bunyavanich) and a pre-activated innate immune system (research (August 2021) by Loske)), and if they do become infected.
Liste der Studien: https://brownstone.org/articles/75-studies-and-articles-against-covid-19-school-closures/