World Health Organization - June 5, 2020


On June 5, The World Health Organization (WHO) released updated guidance on mask usage, including information on who should use a mask and when masks should be worn, as well as the materials or type of mask that should be used. The new recommendations deviate from previous guidance in a few key areas, particularly for areas experiencing widespread SARS-CoV-2 transmission.

The WHO now recommends that masks be worn by all health personnel seeing patients in areas of widespread transmission, not just clinicians treating COVID-19 patients. In areas experiencing community transmission (a step below widespread transmission), individuals at elevated risk of severe COVID-19 disease or death, including those over the age of 60 or those with underlying health conditions, should wear medical masks whenever physical distancing from other people is not possible. The general public should wear masks in crowded areas when physical distancing from other people is not possible in areas experiencing widespread transmission.

In terms of materials, the WHO now recommends that cloth masks be made out of at least 3 layers of different materials, ideally an inner layer of absorbent material (e.g., cotton), a middle layer of non-woven material (e.g., polypropylene), and an outer layer of non-absorbent material (e.g., polyester).

WHO Director-General Dr. Tedros Adhanom Ghebreyesus emphasized that mask use alone does not protect against SARS-CoV-2 infection and that masks should be used as part of a “comprehensive strategy” of protective measures.