WHO changes position on face masks

The World Health Organization (WHO) recommended that in places with widespread transmission of coronavirus, all people who cannot keep the distance of two meters with others, such as in public transport, shops or closed spaces with many people, use cloth masks or face masks.

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In an update to its advice guide on this element of protection, the organization considers that as countries lift confinement measures and movement restrictions, it is necessary for people to use them to protect themselves in situations where they are not you can apply the recommended social distance.

Old recommendation

Until now, the WHO only recommended –according to its guide from last April 6– the use of masks for people who cared for potentially contaminated people, or who had a cough or sneeze; as well as for health personnel.

"Governments should encourage citizens to wear a mask when there is a widespread transmission (of the coronavirus) and it is difficult to establish a social distancing, such as occurs in public transport, in stores or in other crowded or confined places," said the director general of the organization, Tedros Adhanom Ghebreyesus.

"In areas with community transmission, we advise that people over the age of 60, or those with underlying health conditions, wear a medical mask in situations where physical distancing is not possible," he added.

"The masks, by themselves, do not protect against COVID-19"

Tedros stressed that the masks were only part of an effective strategy to suppress the virus and could lead people to a false sense of security. He said they did not replace physical distance or hand hygiene.

"The masks, by themselves, do not protect against COVID-19," he said in a virtual press conference. "Find, isolate, test and take care of each case. Then track and quarantine all contacts. That is what we know does work. That is the best defense in each country against COVID-19," he added.

Cloth face mask

The expert of the Department of Health Emergencies of the WHO, April Beller, explained to Efe that there is new scientific evidence (based on research from the universities of Stanford and Colorado) on cloth masks, the various materials from which they can be made and the level of protection they confer.

Beller explained that the ideal is to combine the fabrics and that the mask has three layers, using the most absorbent material (for example, cotton) closest to the mouth, which will make the saliva drops stay coughy. there.

The WHO guidance guide stresses that not all cloth masks have the same quality of filtration, one of the determining factors for their effectiveness. The materials to consider in the manufacture of an effective mask are polypropylene, cotton and polyester, and cellulose and silk as the last alternatives.

"Distance is the best prevention that exists. If not, why the fabric? Because surgical masks must be kept for healthcare personnel," Beller said.

An exception should be made for people over the age of 60 or with chronic diseases, who are now also recommended by the WHO to wear medical masks.

The three layer mask

Thus, Beller explained that the ideal is to combine the fabrics and that the mask has three layers, using the most absorbent material (for example, cotton) closer to the mouth, which will cause, if coughing, the saliva drops stay there. Outside should go the most water-repellent material, such as polyester, while polypropylene, which is the material used in surgical masks, could be used as a filter (in the middle).

In many countries, the most widely used masks are cotton ones made by hand, either because surgical masks are scarce, because they are reserved for medical personnel or because they are cheaper.

Using them is better than nothing, but the problem they have is that "they absorb a lot of water, so when they get wet you have to change them because they may be contaminated," Beller said.