The World Health Organization (WHO) has recommended a stricter use of face masks amid a second wave of coronavirus infections.
On Wednesday, the WHO tightened guidelines on wearing face coverings, advising that, where COVID-19 is spreading, they be worn by everyone in health care facilities and for all interactions in poorly-ventilated indoor spaces.
It said people – including children and students aged 12 or over – should always wear masks in shops, workplaces and schools that lack adequate ventilation, and when receiving visitors at home in poorly ventilated rooms.
In June, the WHO urged governments to ask everyone to wear fabric masks in indoor and outdoor public areas where there was a risk of transmission of the virus.
Since then, a second global wave of the epidemic has gathered pace which has led to a change in advice.
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In the UK, face coverings are compulsory in shops, supermarkets, public transport and NHS settings such as hospitals and GP surgeries.
The UK government adds in its advice: “If you can, you should also wear a face covering in other enclosed public spaces where social distancing isn’t possible and where you will come into contact with people you do not normally meet.
“This is most relevant for short periods indoors in crowded areas.”
WHO said masks should also be worn outdoors and in well ventilated indoor spaces where physical distancing of at least one metre (3 feet) could not be maintained.
In all scenarios, masks – which protect against transmission of the virus rather than infection – need to be accompanied by other precautions such as handwashing, it added.
In areas of COVID-19 spread, it also advised "universal" wearing of medical masks in health care facilities, including when caring for other patients.
The advice applied to visitors, outpatients and to common areas such as cafeterias and staff rooms.
Health care workers could wear N95 respirator masks if available when caring for COVID-19 patients, but their only proven protection is when they are doing aerosol-generating procedures which carry higher risks, the WHO said.
It recommended that people doing vigorous physical activity not wear masks, citing some associated risks, particularly for people with asthma.
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