Full edition for scientific use. The SARS-CoV2 pandemic affected kindergarten and crèche system thus also the families of kindergarten and crèche children for over a year. The ICKE project (International Corona Daycare Survey) is an international cooperation project between the Clinic for Paediatrics with a focus on Pneumology, Immunology and Intensive Care Medicine Berlin and the International Centre for Professionalisation of Elementary Education (PEP) of the University of Graz with locations in Graz and Berlin. In this study, the prevalence and impact of Covid 19 infections in daycare centers, nurseries, and kindergartens in Germany, Austria, and Switzerland in the second wave (August 2020 to January 2021) were investigated within the framework of two quantitative online surveys addressed to families (N=16756) and daycare center managers or directors (N=3619) of kindergartens or nurseries. The interviews took place from the end of January to March 2021