Covid: When you should and shouldn't wear a mask according to WHO - including in your own home

People wearing face masks pass a Christmas window display on Oxford Street, London Credit: PA Wire/PA Images

People in areas of suspected high coronavirus transmission should wear face masks in schools, at their places of work and even in their own home when guests visit, updated advice suggests.

New World Health Organisation (WHO) advice published on Wednesday recommends the use of face coverings at home when receiving visitors if one-metre distancing cannot be maintained or ventilation is poor.

The advice issued by the UN agency comes despite “limited evidence” of the effectiveness of mask wearing by the public in the community.

In areas with known or suspected spread of Covid-19, the WHO recommends people should wear a mask indoors and outdoors where distancing of at least one metre cannot be maintained.

Masks should be worn indoors regardless of social distancing unless ventilation has been assessed to be adequate, WHO says. Credit: PA

The advice, which applies to shops, schools and shared workplaces, also states masks should be worn indoors regardless of social distancing unless ventilation has been assessed to be adequate.

People should also wear a mask at home when receiving visitors if they cannot maintain distancing or ventilation is poor, the WHO recommends.

Children aged up to five should not wear masks, a “risk-based approach” should be taken for six to 11-year-olds, while those aged 12 and over should follow the same principles as adults, the guidance states.

It also says masks should not be worn during vigorous physical activity.

WHO advises against wearing masks when exercising 'vigorously'. Credit: PA

The WHO said its Covid-19 Guidance Development Group (GDG) “considered all available evidence on the use of masks by the general public including effectiveness, level of certainty and other potential benefits and harms, with respect to transmission scenarios, indoor versus outdoor settings, physical distancing and ventilation”.

The recommendations were made “despite the limited evidence of protective efficacy of mask wearing in community settings”.