By Dilip H. Liyanage –

As the Covid-19 global epidemic rapidly progresses, one debate among the scientific community and public is, use of face masks to prevent further spread of the infection. 

Many governments impose measures in place to control the infection for a reasonable and proportional response. Part of this planning is to mitigate any extra burden of the infection and to ensure the safety of the nations in many countries, while they adopt many other different measures. One of such measure is, general public were urged to wear face coverings in crowded areas.

Currently there is no strong evidence base to show the effectiveness of wearing face masks by the general public in order to reduce the infection rate (R Rate). Ideally there should be a community intervention trial showing the effectiveness of the strategy. Though there are comparisons of the countries that used face masks and not used faced masks, those result could have been affected by a lot of unknown confounding factors.

However, guidance on use of face masks widely varies among international health bodies and governments. Whether wearing a face mask can help prevent the spread of coronavirus has been a divisive subject among health professionals, particularly in the absence of effective pharmacological treatments. The question is, how useful are facemasks during CoVid-19 crisis? What is expert opinion on them? Should we wear it? If so how and who should where them? Do they protect you or the other person and which type of mask makes the most sense? 

This document provides the opinion on the suitability of face masks and other face covers in the community by individuals who are not ill in order to reduce potential transmission of CoVid-19 from the mask wearer to others.

What is the cultural and countries practices?

Many Asian countries regarded facemask as a magic weapon, in the fight against the Covid-19. Some Asian countries even forbid presence on the streets without a mask. But, in Europe mixed feeling regarding wearing mask in a time of resource scarcity. Many believed mask should be reserved for health care workers and sick people to protect other people. Recommendation on such, even in Europe this seems to be change over the time. Now many local authorities do recommend wear face mask in public settings where other physical distancing measures are difficult to maintain especially in areas community-based transmission is significantly high. 

Wearing medical grade masks in public settings 

The World Health Organisation (WHO) is currently only advising those who are sick and showing symptoms of coronavirus to wear a mask, such as coughing or sneezing. If you do not have respiratory symptoms like fever, cough, running nose, you do not need to wear a surgical mask. Masks may create a false sense of security, with neglect of other essential measures such as hand hygiene practices and physical distancing. They may lead to touching the face under the masks and under the eyes. Mask usage may result in unnecessary costs and take masks away from those in health care who need them most, especially when masks are short in supply.  

Mask in the community

Include various forms of self-made or commercial masks or face covers made of cloth, other textiles, or other materials such as paper. They are not standardised and are not intended for use in healthcare settings or by healthcare professionals. It should be emphasised that use of face masks in the community should be considered only as a complementary measure and not as a replacement of the core preventive measures that are recommended to reduce community transmission including physical distancing, staying home, hand hygiene etc. However, there is currently limited or no evidence that the wearing of a mask (whether medical or other types) by healthy persons in the wider community setting, including universal community masking, can prevent them from infection with respiratory viruses, including Covid-19. 

Cloth face coverings

Though evidence on the efficacy and acceptability of the different types of face mask in preventing respiratory infections during epidemics is sparse and contested, millions of people are wearing flimsy masks in the absence of a randomized controlled trial (RCT). In the absence of evidence and evidence of absence, some authorities are asking or compelling public to wear non-surgical masks, to manage scarcity rather than speaking honestly about the effectiveness. 

In addition, masks should not be placed on children under age 2, anybody who has trouble breathing, or is unconscious, incapacitated or otherwise unable to remove the mask without assistance.

Rational usage of medical grade masks in the context of short supply 

Currently for any type of mask, appropriate use, worn and disposal are essential to ensure that they are effective and to avoid any increase in transmission. Many health care institutions make recommendations on correct use of mask if you feel the need to wear.

* Before touching the mask, clean your hands with alcoholic hand rub or soap and water. 

* Inspect the mask for tears or holes. 

* Wear the right side (usually white colour inside) and metal peace is on the top of the mask.

* Fit the mask on your face, pinch the metal strip or stiff edge which it moulds to the shape of the nose. 

* Adjust the mask on your face covering your mouth and chin. Make sure there are no gaps between the face and the mask to avoid the contamination.  

* Remove the mask using the appropriate technique: untie/remove the elastic from behind without touching the front and keeping it away from the face. 

* Discard the mask immediately in closed bin and clean your hand with alcoholic hand rub or soap and water.

* It is important not re-use single-use masks and replace masks as soon as they become damp with a new clean, dry mask.

However, the use of a mask alone is insufficient to provide an adequate level of protection, and other measures should also be adopted. Whether or not masks are used, maximum compliance with hand hygiene and other infection prevention and control measures is critical to prevent human-to-human transmission of Covid-19.

What is the new advice? 

Centre for disease control (CDC) advises and many governments advice, people should wear mask in public places (specially enclosed spaces) in where social distancing measures are “difficult to maintain,” such as supermarkets and pharmacies. The recommendation clearly states that the face coverings should be made at home with low-cost materials and should not lead to the use surgical masks and N-95 respirators which should be reserved for healthcare professional use. 

Could it have negative effects? 

Experts have warned several explanations as to why face masks have not generally been found to be effective if worn by the general population and which can also lead to complacency.

* Do not protect against the virus getting into the eyes (only close-fitting goggles do this); 

* May not fit the masks properly, frequent touching (self-contamination) or take them on and off; and

* False sense of reassurance and thus pay less attention to other key behaviours reducing transmission, such as hand hygiene and physical distancing.”

* Potential reusing contaminated mask

* Potential breathing difficulties, depending on type of mask

* Diversion of mask supplies and consequent shortage of mask for health care workers 

Government responsibility

Whatever approach is taken, it is important to develop a strong communication strategy to explain to the population the circumstances, criteria, and reasons for decisions. The population should receive clear instructions on what masks to wear, when and how and on the importance of continuing to strictly follow all other IPC measures (e.g., hand hygiene, physical distancing, and others).

Acknowledgments

I would like to acknowledge my supervisor Dr. Ian P Reckless, Medical Director, Milton Keynes University Hospital NHS FT, UK and my colleague Dr. Mapa Prabhath Piyasena, Postdoctoral Research Fellow from Ministry of Health – Sri Lanka for their input, support, and expertise in this work.

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