WHO updates guidelines for wearing a mask in indoor, outdoor public areas

The World Health Organisation (WHO) has recently updated its guidelines on wearing a mask in public areas as well as indoors in places where there isn’t sufficient ventilation. This is the WHO’s fourth update on mask guidance during the coronavirus pandemic; the last one came in August. Like it has stated on previous occasions, the guidance stated that a mask itself won’t help in keeping away the SARS-CoV-2 virus. It needs to be used in conjunction with other safety measures namely hand hygiene, the physical distancing of at least one metre, avoidance of touching one’s face, respiratory etiquette, adequate ventilation in indoor settings, testing, contact tracing, quarantine and isolation. With more than 64 million cases, using a mask is necessary in order to stop the spread of the virus from an infected person and protect those who are around them. The global health agency mention face shields as an alternative if one does not have a mask or if a person cannot wear a mask for medical reasons like those with cognitive, respiratory or hearing impairments. However, it states that “they are inferior to masks with respect to droplet transmission and prevention.” But if they have to be used, the face shields cover the sides of the face and below the chin. The health organisation also mentions that it is important to wear a mask in areas of known infection clusters or community transmission. People should wear a ’non-medical mask’ indoors like in shops, workplace, schools and in outdoor areas where maintaining physical distancing is not possible. It also states that if there is poor ventilation indoors, it is important to wear a non-medical mask. This is regardless of whether the social distance is being maintained or no. It is important to either be outdoors or in well-ventilated areas indoors because the virus can spread easily inside. According to the CDC, the risk of being infected with the SARS-CoV-2 virus in enclosed areas is 18.7 higher than outdoors and can also cause super spreader events to occur. Superspreader event is when one infected individual infects an “unusually high” number of people in their proximity causing multiple secondary cases. Health care workers need to wear medical masks in non-aerosol generating procedure and wear N95 respirators, if they are available, in aerosol-generating procedures. In hospitals, everyone needs to wear masks and this applies to visitors, staff, patients, and also in common areas like the cafeterias and staff rooms.

Advice for children

The WHO has stated that children upto five years do not need to wear masks if they are infected for ‘source control’. According to a study in the NCBI, source control is an old term used to control ongoing infection. It involves all the “physical actions taken in the process of care to control” an infection and reduce the “favourable conditions that promote microorganism growth. For children who are between the ages of six to 11, wearing a mask depends on if they actually understand how to properly wear and if there are adults around to supervise, how intense the transmissions is in the area if there are elderly people around, etc. The rules for children and adolescents 12 years and older follow the same as those for adults. But exceptions can be made for children with compromised immunity, paediatric patients with cystic fibrosis or diseases like cancer and for children who are specially-abled.

Here are a few reminders from the WHO:

•  The elderly and those with health issues should always wear a medical mask when the physical distance of atleast one meter is not being maintained.
• Caregivers of those who are suspected or confirmed to be infected should wear a mask when they are in the same room as the patient.
•  Homemade masks should be three-ply with the outermost layer made of a material that repels water and the innermost layer made with a material that can get wet with water. The middle hydrophobic layer should be made with a material that “has been shown to enhance filtration or retain droplets.”
•  Do not use masks with an exhalation valve.
•  Factory-made fabric masks should have proper filtration, be breathable and fit properly.
•  Ensure that the mask covers the mouth and nose and minimize any gaps between the face and the mask.
• Always perform hand hygiene
•  Replace the mask if it becomes damp or wet.
• Do not re-use single-use masks and dispose of properly.
• Do not remove your mask while talks and don’t share masks.