In addition to other mitigation measures, face masks have been used in schools worldwide as a precondition for allowing school attendance during the COVID-19 pandemic. The quality and habits of mask wearing have, however, not been evaluated thus far, leaving uncertainty about the efficacy of this measure. It was the aim of this study to assess the accuracy of face mask wearing by children and adolescents in different school situations. In May and June 2022, students of two selected Austrian schools were asked to provide information about the different variations in wearing a face mask in different situations at school (in classrooms with or without the presence of a teacher, and in school buildings outside classrooms without the presence of a teacher). Strongly divergent results were identified for the amount of time in which face masks were worn correctly in the three different situations (p < 0.001, eta = 0.29). In the presence of a teacher, masks were worn correctly 63.7% of the time, while this percentage decreased to 31.9% when no teacher was present (p < 0.001). These results suggest the limited efficacy of mandatory face masks in schools. Should this measure become necessary again in the future due to the pandemic situation and highly pathogenic variants, special efforts are necessary in order to improve the quality of face mask wearing by school children.
Keywords: COVID-19; classes; face mask; high school; middle school; mitigation measures; school; school children; students; wearing.