Advice on the use of masks in the context of COVID-19 – WHO


According to the current evidence, COVID-19 virus is primarily transmitted between people via respiratory droplets and contact routes. Droplet transmission occurs when a person is in close contact (within 1 metre) with an infected person and exposure to potentially infective respiratory droplets occurs.

N95 vs medical masks:

Meta-analyses in systematic literature reviews have reported that the use of N95 respirators compared with the use of medical masks is not associated with any statistically significant lower risk of the clinical respiratory illness outcomes or laboratory-confirmed influenza or viral infections.

Wearing masks by the general public:

There is limited evidence that wearing a medical mask by healthy individuals in households, in particular those who share a house with a sick person, or among attendees of mass gatherings may be beneficial as a measure preventing transmission.

At present, there is no direct evidence (from studies on COVID-19 and in healthy people in the community) on the effectiveness of universal masking of healthy people in the community to prevent infection with respiratory viruses, including COVID-19.

At the present time, the widespread use of masks by healthy people in the community setting is not yet supported by high quality or direct scientific evidence and there are potential benefits and harms to consider.