SARS-CoV-2 transmission with and without mask wearing or air cleaners in schools in Switzerland: A modeling study of epidemiological, environmental, and molecular data.
https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1004226
SARS-CoV-2 transmission with and without mask wearing or air cleaners in schools in Switzerland: A modeling study of epidemiological, environmental, and molecular data

Nicolas Banholzer and team use a variety of data to investigate the transmission of SARS-CoV-2 in two secondary schools in Switzerland in the presence and absence of mask wearing and air cleaners.

@mackayim2022 Interesting results.I'm not sure the authors are right to discount repeated infections in kids (but that's anecdotal on my part), but it clearly shows (even through the limitations) that masks & ventilation both work.