Masks, the jury returns

RCTs did not show a clear reduction in respiratory viral infection with the use of medical/surgical masks. There were no clear differences between the use of medical/surgical masks compared with N95/P2 respirators in healthcare workers, when used in routine care to reduce respiratory viral infection. Do physical measures such as hand-washing or wearing masks stop or slow down the spread of respiratory viruses? Evidence published up to October 2022. Background Influenza (H1N1) caused by the H1N1pdm09 virus in 2009 Severe acute respiratory syndrome (SARS) in 2003 Coronavirus disease 2019 (COVID-19) Update of a Cochrane Review last published in 2020. We include results from studies from the current COVID-19 pandemic. Main results 11 new RCTs and cluster-RCTs n = 610,872 Bringing the total number of RCTs to 78 Medical/surgical mas