The Science Behind Wearing a Mask

The Science (and More) Behind Wearing a Mask to Protect Yourself and Others

Remedy Report publish date: Friday, July 24, 2020

The Science (and More) Behind Wearing a Mask to Protect Yourself and Others

All over our country right now, there is a debate raging over various local and regional mandates to wear masks to slow the spread of the COVID-19 virus. While politicians and their constituents argue over the science and constitutionality of these orders, scientists, like the Center for Disease Control’s Dr. Anthony Fauci, refer to COVIDnumerous studies that support the idea that face masks are a vital tool in slowing down the spread of the coronavirus. In an effort to help people understand the science behind these mandates and recommendations we are going to take a look at the information studies offer and how these facts have been received over the course of 2020.

Pre-Pandemic Views

Back when we first learned of COVID-19 and before it had hit our shores, public health officials in the United States stated that the public did not have to worry about wearing masks. These views quickly changed as it became evident that asymptomatic carriers of the virus are able to unknowingly infect those around them.

As we came closer to a worldwide pandemic, epidemiologists and infectious disease experts repeatedly suggested masks as a way to slow the progress of the virus but government officials  expressed concern that there was a limited supply of surgical masks available in the U.S. and that they should be saved for the soon-to-Masksbe overrun health care workers. This resulted in an unfortunate amount of mixed messaging. Some also note Americans’ cultural unwillingness to adopt face mask wearing measures early on, before the mandates. In other countries, especially in Asia, face masks are common practice so citizens didn’t regard the suggestion to wear masks with suspicion or surprise. This willingness to adapt has proven extremely helpful in their ability to “flatten the curve”.

Now, in the middle of a full;-blown pandemic, the CDC states that, “(c)loth face coverings are recommended as a simple barrier to help prevent respiratory droplets from traveling into the air and onto other people when the person wearing the cloth face covering coughs, sneezes, talks, or raises their voice. This is called source control. This recommendation is based on what we know about the role respiratory droplets play in the spread of the virus that causes COVID-19, paired with from clinical and laboratory studies that shows cloth face coverings reduce the spray of droplets when worn over the nose and mouth. COVID-19 spreads mainly among people who are in close contact with one another (within about 6 feet), so the use of cloth face coverings is particularly important in settings where people are close to each other or where social distancing is difficult to maintain.”

Still, many Americans continue to make the argument that there is “mixed messaging” from the medical community regarding the importance of wearing a mask and that their recommendations have changed. I read a an article recently comparing the history of COVID-19 and masks to a tornado. If there is a storm brewing outside of Wichita that could cause a twister later in the day the meteorologists aren’t going to be frantic with worry that everyone in Wichita runs into their basement. But if their prediction proves to be correct and a Category 5 tornado is barreling toward the City hours later, we’d want them to sound the alarm, right? The important thing is that they DO warn everyone to take the necessary precautions while they still have time to remain safe and not fall victim to the storm, or in our case, virus.

But What Science Supports This Theory?

There are several convincing studies that support the effectiveness of masks in spreading the virus.

Chart - Transmission

One group of laboratory studies concentrated on respiratory droplets and the effectiveness of masks in blocking their transmission. Experiments using video proved that when saying simple phrases, hundreds of droplets were produced by the speaker but nearly all of the droplets were blocked from traveling when the mouth was covered by a damp washcloth.

Another study published in The Proceedings of the National Academy of Sciences (PNAS) found that requiring people to wear masks in epicenters of new COVID cases may have prevented tens of thousands of infections from the virus. Researchers looked at infection trends in both Wuhan, China and New York City and found that, once local governments inforced mask-wearing mandates, the infection rates took a sharp dive. In NYC, the daily infection rate dropped by 3% per day after the April 17th enforcement and continues to trend downward.

But the strongest and perhaps most influential argument in favor of masks comes from real-world scenarios. Because epidimiologists can’t/won’t ask people to not wear a mask during a pandemic in order to study the results of mask/no-mask transmission, they have turned to real-life examples to educate the public. A study published in Health Affairs compared the virus growth rate both before and after the government-issued mask mandates in 15 states and the District of Columbia. For the first five days following the mandate the daily growth rate slowed by 0.9 percentage points and, at three weeks, the growth rate had dropped two percentage points.

Further evidence was reported when a man flew from China to Toronto while exhibiting symptoms with a dry cough. He tested positive for COVID-19 after arriving in Toronto but, because he wore a mask during the flight, the 25 people closest to him onboard all tested negative. Similarly, two Missouri-based hair stylists who tested positive had close contact with 140 clients while exhibiting symptoms. Because both of them wore masks, not one of those clients tested positive.

A group of internationally renowned scientists from around the World conducted a study comparing various methods used to help reduce infection rates, including lockdown, social distancing and mask wearing. They predicted that 80 percent of the population wearing masks would do more to reduce COVID-19 spread than a strict lockdown, bringing the infection rate down to a shockingly low number. In practice, as of this writing, the latest forecast from the Institute of Health Metrics and Evaluation stated that over 33,000 deaths could be avoided by October 1 if 95 percent of people wore masks in public.

Do Masks Cause Lack of Oxygen or CO2?

FACT: The prolonged use of medical masks* when properly worn, DOES NOT cause CO2 intoxication nor oxygen deficiency.

In April of this year The World Health Organization stated that “(t)he prolonged use of medical masks can be uncomfortable. However, it does not lead to CO2 intoxication nor oxygen deficiency. While wearing a medical mask, make sure it fits properly and that it is tight enough to allow you to breathe normally. Do not re-use a disposable mask and always change it as soon as it gets damp.”

WHO Chart

To once again put it into real-life terms, surgeons have been wearing masks during long periods of time for decades and, let’s be honest, what they’re doing while wearing those masks is far more taxing than shopping at the local TJ Maxx. If they’re not suffering from CO2 intoxication, it should follow that neither will the average American.

*Medical masks (also known as surgical masks) are flat or pleated; they are affixed to the head with straps or have ear loops. See graphic above.

Exceptions – Who Is Exempt?

In all states requiring masks in public, there are, of course, exemptions for those suffering from certain medical conditions. I’ve heard of a number of individuals claiming to fall under those exemptions because of skin irritation, anxiety and, in one case, allergies.  In my home state of North Carolina, Governor Roy Cooper has issued an executive order requiring all citizens to wear masks in public areas such as retail stores, restaurants (though patrons are able to remove masks at their tables), government buildings, salons and “any place social distancing is difficult”. Those who are exempt from this order are:

  • Has a medical or behavioral condition or disability.
  • Those under 11-years-old.
  • Someone who is actively eating or drinking.
  • Someone who is exercising.
  • While trying to communicate with someone who is hearing impaired and needs the mouth to be visible.
  • If you’re working from home or in a vehicle.
  • If you’re temporarily removing your mask for identification purposes.
  • Would be at risk for wearing a face covering, as determined by local, state or federal regulations or workplace safety guidelines.
  • If the masks makes is difficult to operate equipment or a vehicle.
  • A child whose guardian is unable to put the mask safely on the child’s face.

These regulations sound reasonable, right? But what exactly constitutes a “medical or behavioral condition or disability”, according to the order? Well this exemption includes, but is not limited to,  “any person who has trouble breathing, or is unconscious or incapacitated, or is otherwise unable to put on or remove the face covering without assistance”. Common sense tells us that when debating the pros and cons of masking we aren’t talking about someone who is unconscious or disabled to the point of needing help to put on or remove the mask. And discomfort does not translate into not being able to draw a breath. Uncomfortable? Sure thing. Debilitating? Probably not.

Surgical v. Cloth – Which Masks Work?

Medical professionals agree that wearing an N95 surgical mask is an excellent way to safeguard against possible infection but, especially for long-term use, it isn’t a very comfortable option. While it is true that the surgical masks generally offer a more stringent barrier, most people would wear the “breathable” cloth masks more often and for longer periods of time. Obviously the N95 masks are necessary for medical professionals who are exposed to the coronavirus multiple times in an hour but for the general public the best mask is the mask they will wear comfortably and consistently. Remember that the goal is to REDUCE the risk, not prevent exposure completely. To do that, complete quarantine is the best option. Masks are recommended for those who feel they must go out in public and should serve as a method to lessen the chances of infection.

A study  published in Cambridge University Press examined “homemade” masks and their capacity to block bacterial and viral aerosols in comparison to commercially sold face masks. Several materials found in most homes and used as a makeshift mask were evaluated for effectiveness. Twenty one healthy volunteers used cotton t-shirts, which were tested for fit, to shield their faces from coughs. When compared to surgical masks, the t-shirts masks were found to have one half the “median-fit factor” and were three times less effective in blocking transmission of microorganisms produced by the coughs. However, when compared to volunteers who wore NO masks, the cotton t-shirt significantly reduced the number of aerosols expelled. In the end, their findings suggested that, although the homemade masks should be “considered a last resort to prevent droplet transmission from infected individuals”, “it would be better than no protection”. 

The Ethics of Wearing a Mask

It is a fact that some Americans will either ignore or not believe scientific evidence and choose not to wear a mask in public. In most cases, this is absolutely their legal right…but what about the rights of those around them to be protected from the Virus? Don’t we all have a moral and ethical responsibility to look out for our fellow Americans? Signally to others that we are respecting their safety (even if not worrying about our own) is an arguably “American” show of solidarity. We have faced uncertainty in the past and our ability to work together as a country has been one of our greatest and most unique abilities. Something as simple as wearing a mask infringes so minimally on personal comfort but, like safe driving, can have a huge positive impact on the greater community. C’mon, fellow Americans…..LET’S MASK UP!

All over our country right now, there is a debate raging over various local and regional mandates to wear masks to slow the spread of the COVID-19 virus. While politicians and their constituents argue over the science and constitutionality of these orders, scientists, like the Center for Disease Control’s Dr. Anthony Fauci, refer to COVIDnumerous studies that support the idea that face masks are a vital tool in slowing down the spread of the coronavirus. In an effort to help people understand the science behind these mandates and recommendations we are going to take a look at the information studies offer and how these facts have been received over the course of 2020.

Pre-Pandemic Views

Back when we first learned of COVID-19 and before it had hit our shores, public health officials in the United States stated that the public did not have to worry about wearing masks. These views quickly changed as it became evident that asymptomatic carriers of the virus are able to unknowingly infect those around them.

As we came closer to a worldwide pandemic, epidemiologists and infectious disease experts repeatedly suggested masks as a way to slow the progress of the virus but government officials  expressed concern that there was a limited supply of surgical masks available in the U.S. and that they should be saved for the soon-to-Masksbe overrun health care workers. This resulted in an unfortunate amount of mixed messaging. Some also note Americans’ cultural unwillingness to adopt face mask wearing measures early on, before the mandates. In other countries, especially in Asia, face masks are common practice so citizens didn’t regard the suggestion to wear masks with suspicion or surprise. This willingness to adapt has proven extremely helpful in their ability to “flatten the curve”.

Now, in the middle of a full;-blown pandemic, the CDC states that, “(c)loth face coverings are recommended as a simple barrier to help prevent respiratory droplets from traveling into the air and onto other people when the person wearing the cloth face covering coughs, sneezes, talks, or raises their voice. This is called source control. This recommendation is based on what we know about the role respiratory droplets play in the spread of the virus that causes COVID-19, paired with from clinical and laboratory studies that shows cloth face coverings reduce the spray of droplets when worn over the nose and mouth. COVID-19 spreads mainly among people who are in close contact with one another (within about 6 feet), so the use of cloth face coverings is particularly important in settings where people are close to each other or where social distancing is difficult to maintain.”

Still, many Americans continue to make the argument that there is “mixed messaging” from the medical community regarding the importance of wearing a mask and that their recommendations have changed. I read a an article recently comparing the history of COVID-19 and masks to a tornado. If there is a storm brewing outside of Wichita that could cause a twister later in the day the meteorologists aren’t going to be frantic with worry that everyone in Wichita runs into their basement. But if their prediction proves to be correct and a Category 5 tornado is barreling toward the City hours later, we’d want them to sound the alarm, right? The important thing is that they DO warn everyone to take the necessary precautions while they still have time to remain safe and not fall victim to the storm, or in our case, virus.

But What Science Supports This Theory?

There are several convincing studies that support the effectiveness of masks in spreading the virus.

Chart - Transmission

One group of laboratory studies concentrated on respiratory droplets and the effectiveness of masks in blocking their transmission. Experiments using video proved that when saying simple phrases, hundreds of droplets were produced by the speaker but nearly all of the droplets were blocked from traveling when the mouth was covered by a damp washcloth.

Another study published in The Proceedings of the National Academy of Sciences (PNAS) found that requiring people to wear masks in epicenters of new COVID cases may have prevented tens of thousands of infections from the virus. Researchers looked at infection trends in both Wuhan, China and New York City and found that, once local governments inforced mask-wearing mandates, the infection rates took a sharp dive. In NYC, the daily infection rate dropped by 3% per day after the April 17th enforcement and continues to trend downward.

But the strongest and perhaps most influential argument in favor of masks comes from real-world scenarios. Because epidimiologists can’t/won’t ask people to not wear a mask during a pandemic in order to study the results of mask/no-mask transmission, they have turned to real-life examples to educate the public. A study published in Health Affairs compared the virus growth rate both before and after the government-issued mask mandates in 15 states and the District of Columbia. For the first five days following the mandate the daily growth rate slowed by 0.9 percentage points and, at three weeks, the growth rate had dropped two percentage points.

Further evidence was reported when a man flew from China to Toronto while exhibiting symptoms with a dry cough. He tested positive for COVID-19 after arriving in Toronto but, because he wore a mask during the flight, the 25 people closest to him onboard all tested negative. Similarly, two Missouri-based hair stylists who tested positive had close contact with 140 clients while exhibiting symptoms. Because both of them wore masks, not one of those clients tested positive.

A group of internationally renowned scientists from around the World conducted a study comparing various methods used to help reduce infection rates, including lockdown, social distancing and mask wearing. They predicted that 80 percent of the population wearing masks would do more to reduce COVID-19 spread than a strict lockdown, bringing the infection rate down to a shockingly low number. In practice, as of this writing, the latest forecast from the Institute of Health Metrics and Evaluation stated that over 33,000 deaths could be avoided by October 1 if 95 percent of people wore masks in public.

Do Masks Cause Lack of Oxygen or CO2?

FACT: The prolonged use of medical masks* when properly worn, DOES NOT cause CO2 intoxication nor oxygen deficiency.

In April of this year The World Health Organization stated that “(t)he prolonged use of medical masks can be uncomfortable. However, it does not lead to CO2 intoxication nor oxygen deficiency. While wearing a medical mask, make sure it fits properly and that it is tight enough to allow you to breathe normally. Do not re-use a disposable mask and always change it as soon as it gets damp.”

WHO Chart

To once again put it into real-life terms, surgeons have been wearing masks during long periods of time for decades and, let’s be honest, what they’re doing while wearing those masks is far more taxing than shopping at the local TJ Maxx. If they’re not suffering from CO2 intoxication, it should follow that neither will the average American.

*Medical masks (also known as surgical masks) are flat or pleated; they are affixed to the head with straps or have ear loops. See graphic above.

Exceptions – Who Is Exempt?

In all states requiring masks in public, there are, of course, exemptions for those suffering from certain medical conditions. I’ve heard of a number of individuals claiming to fall under those exemptions because of skin irritation, anxiety and, in one case, allergies.  In my home state of North Carolina, Governor Roy Cooper has issued an executive order requiring all citizens to wear masks in public areas such as retail stores, restaurants (though patrons are able to remove masks at their tables), government buildings, salons and “any place social distancing is difficult”. Those who are exempt from this order are:

  • Has a medical or behavioral condition or disability.
  • Those under 11-years-old.
  • Someone who is actively eating or drinking.
  • Someone who is exercising.
  • While trying to communicate with someone who is hearing impaired and needs the mouth to be visible.
  • If you’re working from home or in a vehicle.
  • If you’re temporarily removing your mask for identification purposes.
  • Would be at risk for wearing a face covering, as determined by local, state or federal regulations or workplace safety guidelines.
  • If the masks makes is difficult to operate equipment or a vehicle.
  • A child whose guardian is unable to put the mask safely on the child’s face.

These regulations sound reasonable, right? But what exactly constitutes a “medical or behavioral condition or disability”, according to the order? Well this exemption includes, but is not limited to,  “any person who has trouble breathing, or is unconscious or incapacitated, or is otherwise unable to put on or remove the face covering without assistance”. Common sense tells us that when debating the pros and cons of masking we aren’t talking about someone who is unconscious or disabled to the point of needing help to put on or remove the mask. And discomfort does not translate into not being able to draw a breath. Uncomfortable? Sure thing. Debilitating? Probably not.

Surgical v. Cloth – Which Masks Work?

Medical professionals agree that wearing an N95 surgical mask is an excellent way to safeguard against possible infection but, especially for long-term use, it isn’t a very comfortable option. While it is true that the surgical masks generally offer a more stringent barrier, most people would wear the “breathable” cloth masks more often and for longer periods of time. Obviously the N95 masks are necessary for medical professionals who are exposed to the coronavirus multiple times in an hour but for the general public the best mask is the mask they will wear comfortably and consistently. Remember that the goal is to REDUCE the risk, not prevent exposure completely. To do that, complete quarantine is the best option. Masks are recommended for those who feel they must go out in public and should serve as a method to lessen the chances of infection.

A study  published in Cambridge University Press examined “homemade” masks and their capacity to block bacterial and viral aerosols in comparison to commercially sold face masks. Several materials found in most homes and used as a makeshift mask were evaluated for effectiveness. Twenty one healthy volunteers used cotton t-shirts, which were tested for fit, to shield their faces from coughs. When compared to surgical masks, the t-shirts masks were found to have one half the “median-fit factor” and were three times less effective in blocking transmission of microorganisms produced by the coughs. However, when compared to volunteers who wore NO masks, the cotton t-shirt significantly reduced the number of aerosols expelled. In the end, their findings suggested that, although the homemade masks should be “considered a last resort to prevent droplet transmission from infected individuals”, “it would be better than no protection”. 

The Ethics of Wearing a Mask

It is a fact that some Americans will either ignore or not believe scientific evidence and choose not to wear a mask in public. In most cases, this is absolutely their legal right…but what about the rights of those around them to be protected from the Virus? Don’t we all have a moral and ethical responsibility to look out for our fellow Americans? Signally to others that we are respecting their safety (even if not worrying about our own) is an arguably “American” show of solidarity. We have faced uncertainty in the past and our ability to work together as a country has been one of our greatest and most unique abilities. Something as simple as wearing a mask infringes so minimally on personal comfort but, like safe driving, can have a huge positive impact on the greater community. C’mon, fellow Americans…..LET’S MASK UP!

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