Under-diagnosis of SARS-CoV-2 infections among children aged 0-15 years, a nationwide seroprevalence study, Israel, January 2020 to March 2021.

Until recently, children and adolescents were not eligible for COVID-19 vaccination. They may have been a considerable source of SARS-CoV-2 spread. We evaluated SARS-CoV-2 IgG antibody seroprevalence in Israeli children aged 0-15 years from January 2020 to March 2021. Seropositivity was 1.8-5.5 times higher than COVID-19 incidence rates based on PCR testing. We found that SARS-CoV-2 infection among children is more prevalent than previously thought and emphasise the importance of seroprevalence studies to accurately estimate exposure.