Pasi Pohjola: The best way to avoid coronavirus infection

The recent public discussion on face masks has been lively and varied. Knowledge and scientific evidence have been used quite well, but also in a way that is too selective and prone to overinterpretation. Unfortunately, all too few have considered the matter relative to the epidemic situation in our country and the primary means to prevent infections.

Both the World Health Organization WHO and European Centre for Disease Prevention and Control ECDC have stresses that, during the coronavirus epidemic, the key means to prevent infections are a safe physical distance, good hand hygiene and good coughing and sneezing hygiene. By following these, infections can be reduced in all stages of the epidemic. ECDC stated on 8 April that face masks can be used as secondary means in situations when there is no certainty that the primary means are used or adequate. Even then, ECDC stressed that the scientific evidence for this recommendation is weak.

WHO updated its advice on the use of masks on 5 June. In the updated advice the use of face masks is recommended in specific situations and settings with respect to the epidemic as part of a comprehensive approach to suppress transmissions. WHO’s recommendation concerns epidemic situations where the incidence of new cases is high and growing and the source of the virus and the transmission chain cannot be traced.

In countries where this is still the case WHO recommends the use of cloth masks for citizens in situations where safe physical distances and good hygiene cannot be guaranteed. However, in the updated advice WHO also stresses that there is no high-quality and direct evidence of the effectiveness of face masks in protecting against the virus. In the national guidance we must also take into account both the advantages and disadvantages involved if face masks were taken into extensive use.

More research needed

There is comprehensive evidence of the role of physical distance and hygiene in preventing infections. Instead, there is no similar evidence concerning the use of face masks among the general population. This message was also made clear in the meta-analysis published in the Lancet on 1 June, which stresses the strong evidence concerning the impact of physical distancing on preventing transmission. Besides this, the article calls for randomised trials on the effectiveness of masks other than those intended for healthcare use in preventing transmission in everyday environments (non-health-care settings).

In some countries, people have been obliged to use face masks or this is recommended, and in some settings wearing a masks is considered polite. However, in the Nordic countries no recommendations concerning coverings have been issued. Within Europe, the development of the epidemic has been quite similar in different countries regardless of the decisions made in terms of face masks. Very likely we can only assess in retrospect whether extensive use of face masks had an impact on how the epidemic situation developed.
 

Pasi Pohjola

Director

Ministry of Social Affairs and Health