The Power of Masks

June 23, 2020 Joe Brady

Two hairstylists in Springfield, Missouri, tested positive for COVID-19 in late May. Together they had seen 140 customers since the salon reopened. They may have been contagious the whole time. But instead of detecting a cluster of new cases, local public-health had 46 salon customers tested for the virus, not one was positive. The reason is attributed to the universal wearing of masks by both stylists and customers. The science is beginning to back up what many have known for a while, that masks are our most powerful weapon in the fight against COVID-19. 

There is a growing body of evidence that wearing face masks can slow the transmission of coronavirus and can potentially save many lives. One recent study published in the Proceedings of the Royal Society in the UK found that even adopting face masks 120 days after the beginning of an outbreak of COVID 100% wearing of masks by the public could completely stop the occurrence of further waves of coronavirus. This study and many others are showing that, when facemasks are used by the public all the time (not just from when symptoms first appear), the effective reproduction number, Re, can be decreased below 1, leading to the mitigation of epidemic spread. In other words, even at this late hour, we can stop the spread of this disease by the widespread adoption of wearing masks even before symptoms begin to show.

These analyses may explain why some countries, where adoption of facemask use by the public is around 100%, have experienced significantly lower rates of COVID-19 spread and associated deaths. current studies are showing that facemask use by the public, when used in combination with physical distancing or periods of lock-down, may provide an acceptable way of managing the COVID- 19 pandemic and re-opening economic activity. These results are especially relevant to the developing world, where large numbers of people are resource-poor, but fabrication of home-made, effective facemasks is possible. In Taiwan, Singapore, South Korea, Vietnam, and many other Asian countries they have managed to effectively reduce the number of cases and deaths with almost universal mask-wearing.

Stutt ROJH, Retkute R, Bradley M, Gilligan CA, Colvin J. 2020 A modeling framework to assess the likely effectiveness of facemasks in combination with ‘lock-down’ in managing the COVID-19 pandemic. Proc. R. Soc. A 476: 20200376.

It is much easier in Asian countries to get the public to wear masks because with 322 pandemics in Asia in the last 2000 years, they have a long history of doing so. The custom of wearing masks in Asia to ward off diseases has its origins in ancient Chinese medicine. In ancient Chinese culture, masks were thought of as being a form of communication between mortal men and the immortal gods. They were thought to bring blessings, drive away evil spirits, ward off diseases, and protect the owner from various disasters. In the 13th century, Italian explorer Marco Polo recounted how servants in the Yuan dynasty court were required to cover their noses and mouths with a cloth of silk and gold thread when serving food to the emperor. In late 1910, the legendary Malaysian-Chinese doctor Wu Lien-teh was serving as China’s chief medical officer when an epidemic broke out in Northeast China. Wu went deep into the affected areas to lead prevention and control work and soon identified the epidemic as a form of pneumonic plague spread by droplets in the air. In addition to proposing now-familiar-sounding measures — including quarantining patients and cordoning off many cities — Wu also designed and invented a cheap sanitary face mask that promised some protection from the disease.

In the US the public and even the public health authorities resisted the idea of the ordinary people wearing masks. Recently DR. Anthony Fauci admitted that public health officials downplayed the efficacy of masks to ensure they would be available for health care workers. The World Health Organization and the CDC both recommended that people not wear masks. Our own Surgeon general Jerome Adams said” they are not effective in preventing the general public from catching coronavirus, but if healthcare providers can’t get them to care for sick patients it puts them and our communities at risk”. (February 29th, 2020) Months later now, Dr. Anthony Fauci assured people that “masks do work and act as a protection for both healthy people and to prevent infected individuals from spreading the infection to others”. Since then the use of face coverings has become mandatory in most places including businesses, especially for employees. 

Confusing recommendations continue

The public health recommendations in the US continue to be confusing. One recommendation says people should wear masks when they leave their homes. Another recommends people wear a mask if they cannot properly social distance. In Denver, face masks are not required when exercising outside. But the U.S. Centers for Disease Control and Prevention still recommends people wear cloth face coverings when out in public, especially in places where it’s hard to stay at least 6 feet away from others.

If it’s difficult to breathe through a mask when running or doing other strenuous physical activity, find uncrowded trails or times to exercise when you won’t encounter others, says Mark Cameron, an infectious disease expert at Case Western Reserve University.

Now the CDC is planning to update its recommendation on face masks. Researchers have been conducting a scientific review about the use of masks during the pandemic.

Scientists wanted to study to see if the masks protect people from contracting COVID-19 and not just preventing them from spreading it.

The new guidance is expected to be released soon, better late than never.

A key message from these latest studies to aid the widespread adoption of facemasks would be: ‘my mask protects you, your mask protects me’.


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