Monday, May 25, 2020

Face masks

In these days that the coronavirus rules the world, we see a new phenomenon: People publicly wear face masks. Also in the past (especially in East Asia) people sometimes wore them in public, usually in order to prevent that others would be infected when you had caught a cold or when the air was seriously polluted. But never before people used face masks on such a large scale in order to protect themselves and others against a nasty virus, the coronavirus. Some wear it voluntarily, others do it while the authorities have ordered it; or while it is prescribed in public transport or in shops; and so on. And it looks reasonable to wear a face mask in order to stop the coronavirus, doesn’t it? Nevertheless, wearing a face mask for this reason is not undisputed. This is what the Dutch National Institute for Public Health and the Environment (RIVM), which advises the Dutch government, says about it:
- Wearing a face mask in daily life has no surplus value.
- Face masks have only sense, if there are patients who are seriously ill and who spread many viruses.
- Face masks must be used in the proper way and must be replaced at least twice a day.
- Therefore, in the Netherlands face masks are recommended only for medical personnel.
So, according to the RIVM it has no sense to wear face masks in public. Not only the RIVM says so. Also the World Health Organisation (WHO) doesn’t recommend them. And indeed, investigations into the effectiveness of face makes against infections of the same type show that their public use is not very useful. For instance:
- In twelve relevant investigations only three show a positive effect of wearing face masks. Moreover, the chance to become ill decreased with only 6%.
- An Australian research team investigated in Vietnam about 1,600 people wearing face masks. Some used official face masks, some used cloth face mask. The latter group caught more viruses than without a face mask, so they were worse off.
Studies like these confirm the views of the RIVM and the WHO. I think that such studies show that a good face mask – not necessarily a medical face mask – properly used may have some sense and may decrease the chance to become ill somewhat. But how much is somewhat? 6%, 12%, 25%, 40%? However, the practice is that face masks in public are not properly used and for that reason they may be counterproductive: People can get more viruses just by using face masks. Then they have more chance to become ill. Nevertheless, authorities often prescribe face masks against the spread of the coronavirus and many people use them, not only because they are prescribed but because they think it helps. Why? I think that there are several sociological and psychological factors that are relevant:
- It is counterintuitive, so against intuition, not to use a face mask. A face mask looks like a screen that stops the virus. However, people don’t realize that viruses are very small. You cannot see them and they can pass holes so little that you can’t see them. Viruses, caught in the mask can be spread by your hands, if you touch the face mask. Sooner than you realize, face masks become dirty. Etc.
- People are imitators: Other people wear them as well, and are they so stupid that they wear them, if they are not useful? Moreover, many people feel ill at ease if they are one of the few who don’t do what everybody considers normal.
- Authorities prescribe them, so it must make sense. But authorities often don’t follow expert advice (and as shown above, expert advice – at least the RIVM and WHO – discourages from non-medical use of face mask). Besides, you can be fined if wearing a face mask is prescribed by law and you don’t use it.
- However, if people wear face masks, they become on the alert that they must be careful and that a nasty virus is about everywhere, and that it is better to keep distance from others.
- On the other hand, a face mask can give you the false idea that you are protected and/or that others are protected against your viruses. Then it can happen that people who have only mild complaints don’t stay at home thinking that they will not infect others.
Should we use face masks or shouldn’t we? I think that only one conclusion is possible: Be careful and stay safe.

- De Volkskrant, 8 May 2020

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