Mass masking in the COVID-19 epidemic: people need guidance

WHO recommends against wearing masks in community settings because of lack of evidence.2 However, absence of evidence of effectiveness should not be equated to evidence of ineffectiveness, especially when facing a novel situation with limited alternative options. It has long been recommended that for respiratory infections like influenza, affected patients should wear masks to limit droplet spread. If everyone puts on a mask in public places, it would help to remove stigmatisation that has hitherto discouraged masking of symptomatic patients in many places.3 Furthermore, transmission from asymptomatic infected individuals has been documented for COVID-19, and viral load is particularly high at early disease stage.4 , 5 Masking, as a public health intervention, would probably intercept the transmission link and prevent these apparently healthy infectious sources.