Ages 5-13 included in the study.
Link to paper:
www.eurosurveillance.org/content/10.2807/1560-7917.ES.2020.26.1.2002011
“ This prospective study shows that transmission of SARS-CoV-2 from children under 14 years of age was minimal in primary schools in Oslo and Viken, the two Norwegian counties with the highest COVID-19 incidence and in which 35% of the Norwegian population resides.”