Are Face Masks Effective? The Evidence.

[Leongsam]

Are Face Masks Effective? The Evidence.


Updated: March 2021; Published: July 2020
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An overview of the current evidence regarding the effectiveness of face masks.

1. Studies on the effectiveness of face masks

So far, most studies found little to no evidence for the effectiveness of cloth face masks in the general population, neither as personal protective equipment nor as a source control.

1. A May 2020 meta-study on pandemic influenza published by the US CDC found that face masks had no effect, neither as personal protective equipment nor as a source control. (Source)
2. A Danish randomized controlled trial with 6000 participants, published in the Annals of Internal Medicine in November 2020, found no statistically significant effect of high-quality medical face masks against SARS-CoV-2 infection in a community setting. (Source)
3. A February 2021 review by the European CDC found no significant evidence supporting the effectiveness of non-medical and medical face masks in the community. Furthermore, the European CDC advises against the use of FFP2/N95 respirators by the general public. (Source)
4. A July 2020 review by the Oxford Centre for Evidence-Based Medicine found that there is no evidence for the effectiveness of cloth masks against virus infection or transmission. (Source)
5. A November 2020 Cochrane review found that face masks did not reduce influenza-like illness (ILI) cases, neither in the general population nor in health care workers. (Source)
6. A May 2020 cross-country study by the University of East Anglia (preprint) found that a mask requirement was of no benefit and could even increase the risk of infection. (Source)
7. An April 2020 review by two US professors in respiratory and infectious disease from the University of Illinois concluded that face masks have no effect in everyday life, neither as self-protection nor to protect third parties (so-called source control). (Source)
8. An article in the New England Journal of Medicine from May 2020 came to the conclusion that cloth face masks offer little to no protection in everyday life. (Source)
9. A 2015 study in the British Medical Journal BMJ Open found that cloth masks were penetrated by 97% of particles and may increase infection risk by retaining moisture or repeated use. (Source)
10. An August 2020 review by a German professor in virology, epidemiology and hygiene found that there is no evidence for the effectiveness of cloth face masks and that the improper daily use of masks by the public may in fact lead to an increase in infections. (Source)

Development of cases after mask mandates

In many states, coronavirus infections strongly increased after mask mandates had been introduced. The following charts show the typical examples of Austria, Belgium, France, Germany, Ireland, Italy, Spain, the UK, California and Hawaii. Furthermore, a direct comparison between US states with and without mask mandates indicates that mask mandates have made no difference.




























Mask mandates and coronavirus infections (Source: Yinon Weiss)

Additional aspects

1. There is increasing evidence that the novel coronavirus is transmitted, at least in indoor settings, not only by droplets but also by smaller aerosols. However, due to their large pore size and poor fit, cloth masks cannot filter out aerosols (see video analysis below): over 90% of aerosols penetrate or bypass the mask and fill a medium-sized room within minutes.
2. The WHO admitted to the BBC that its June 2020 mask policy update was due not to new evidence but “political lobbying”: “We had been told by various sources WHO committee reviewing the evidence had not backed masks but they recommended them due to political lobbying. This point was put to WHO who did not deny.” (D. Cohen, BBC Medical Corresponent).
3. To date, the only randomized controlled trial (RCT) on face masks against SARS-CoV-2 infection in a community setting found no statistically significant benefit (see above). However, three major journals refused to publish this study, delaying its publication by several months.
4. An analysis by the US CDC found that 85% of people infected with the new coronavirus reported wearing a mask “always” (70.6%) or “often” (14.4%). Compared to the control group of uninfected people, always wearing a mask did not reduce the risk of infection.
5. Researchers from the University of Minnesota found that the infectious dose of SARS-CoV-2 is just 300 virions (viral particles), whereas a single minute of normal speaking may generate more than 750,000 virions, making cloth face masks unlikely to prevent an infection.
6. Japan, despite its widespread use of face masks, experienced its most recent influenza epidemic with more than 5 million people falling ill just one year ago, in January and February 2019. However, unlike SARS-CoV-2, the influenza virus is easily transmitted by children, too.
7. Austrian scientists found that the introduction, retraction and re-introduction of a face mask mandate in Austria had no influence on the coronavirus infection rate. Moreover, German analysts found that N95/FFP2 masks, too, had no influence on the infection rate.
8. In the US state of Kansas, the 90 counties without mask mandates had lower coronavirus infection rates than the 15 counties with mask mandates. To hide this fact, the Kansas health department tried to manipulate the official statistics and data presentation.
9. Contrary to common belief, studies in hospitals found that the wearing of a medical mask by surgeons during operations didn’t reduce post-operative bacterial wound infections in patients.
10. During the notorious 1918 influenza pandemic, the use of cloth face masks among the general population was widespread and in some places mandatory, but they made no difference.
11. Asian countries with low covid infection rates, most of them neighboring China, benefited not from face masks but mainly from early border closures. This is confirmed by Scandinavian countries Norway, Finland and Denmark, which didn’t introduce mask mandates but closed borders early and saw very low covid infection and death rates, too.
12. German scientists found that in and on N95 (FFP2) masks, the novel coronavirus remains infectious for several days, much longer than on most other materials, thus significantly increasing the risk of infection by touching or reusing such masks.

Dr. Theodore Noel explains the facemask aerosol issue


2. Studies claiming face masks are effective

Some recent studies argued that cloth face masks are indeed effective against the new coronavirus and could at least prevent the infection of other people. However, most of these studies suffer from poor methodology and sometimes show the opposite of what they claim.


Typically, these studies ignore the effect of other measures, the natural development of infection numbers, changes in test activity, or they compare countries with very different conditions.


An overview:

1. A meta-study in the journal Lancet, commissioned by the WHO, claimed that masks “could” lead to a reduction in the risk of infection, but the studies considered mainly N95 respirators in a hospital setting, not cloth masks in a community setting, the strength of the evidence was reported as “low”, and experts found numerous flaws in the study. Professor Peter Jueni, epidemiologist at the University of Toronto, called the WHO study “essentially useless”.
2. A study in the journal PNAS claimed that masks had led to a decrease in infections in three global hotspots (including New York City), but the study did not take into account the natural decrease in infections and other simultaneous measures. The study was so flawed that over 40 scientists recommended that the study be withdrawn.
3. A US study claimed that US counties with mask mandates had lower Covid infection and hospitalization rates, but the authors had to withdraw their study as infections and hospitalizations increased in many of these counties shortly after the study was published.
4. A German study claimed that the introduction of mandatory face masks in German cities had led to a decrease in infections. But the data does not support this claim: in some cities there was no change, in others a decrease, in others an increase in infections (see graph below). The city of Jena was an ‘exception’ only because it simultaneously introduced the strictest quarantine rules in Germany, but the study did not mention this.
5. A Canadian study claimed that countries with mandatory masks had fewer deaths than countries without mandatory masks. But the study compared African, Latin American, Asian and Eastern European countries with very different infection rates and population structures.
6. A review by the University of Oxford claimed that face masks are effective, but it was based on studies about SARS-1 and in health care settings, not in community settings.
7. A review by members of the lobby group ‘Masks for All’, published in the journal PNAS, claimed that masks are effective as a source control against aerosol transmission in the community, but the review provided no real-world evidence supporting this proposition.

Mandatory masks in German cities: no relevant impact. (IZA 2020)
3. Risks associated with face masks

Wearing masks for a prolonged period of time is not harmless, as the following evidence shows:

1. The WHO warns of various “side effects” such as difficulty breathing and skin rashes.
2. Tests conducted by the University Hospital of Leipzig in Germany have shown that face masks significantly reduce the resilience and performance of healthy adults.
3. A German psychological study with about 1000 participants found “severe psychosocial consequences” due to the introduction of mandatory face masks in Germany.
4. The Hamburg Environmental Institute warned of the inhalation of chlorine compounds in polyester masks as well as problems in connection with face mask disposal.
5. The European rapid alert system RAPEX has already recalled 70 mask models because they did not meet EU quality standards and could lead to “serious risks”.
6. In Germany, two 13-year-old children died suddenly while wearing a mask for a prolonged period of time; autopsies couldn’t exclude CO2 intoxication or a sudden cardiac arrest.
7. In China, several children who had to wear a mask during sports classes fainted and died; the autopsies found a sudden cardiac arrest as the probable cause of death.
8. In the US, a car driver wearing an N95 (FFP2) mask fainted and crashed into a pole.

Conclusion

Cloth face masks in the general population might be effective, at least in some circumstances, but there is currently little to no evidence supporting this proposition. If the coronavirus is indeed transmitted via indoor aerosols, cloth masks are unlikely to be protective. Health authorities should therefore not assume or suggest that cloth face masks will reduce the rate or risk of infection.

See also

• Facts about Covid-19
• Studies on Covid-19 lethality
• On the treatment of Covid-19

 

[Leongsam]

 

[Leongsam]

 

[Thick Face Black Heart]

Facemasks are not effective for the general public because people don't wear them properly.

I only see doctors and nurses wearing them properly. That is why they are able to prevent cross infection in the OT.

If people wore masks properly and fucking washed their hands, this pandemic would slow down significantly.

 

[Thick Face Black Heart]

Being trained in statistics (although from a theoretical rather than applied standpoint), I can also smell bullshit a mile away. The graphs that Leongsam posted exhibit what we call "spurious correlation". Marking out the point whether infection rates increased, and then claiming it is due to facemask wearing. This is silly. Facemask wearing did not case infection rates to increase. They are correlated because they are caused by a other confounding variables such as viral mutations. It is also well known that when the infection rates go above a treshold amount, they will explode suddenly. This is due to nonlinear nature of the differential equations commonly used to model.

Don't try to BS me, Leongsam

 

[STUCK_HERE]

Your dare to be different is old and incredibly boring.

 

[Leongsam]

Being trained in statistics (although from a theoretical rather than applied standpoint), I can also smell bullshit a mile away. The graphs that Leongsam posted exhibit what we call "spurious correlation". Marking out the point whether infection rates increased, and then claiming it is due to facemask wearing. This is silly. Facemask wearing did not case infection rates to increase. They are correlated because they are caused by a other confounding variables such as viral mutations. It is also well known that when the infection rates go above a treshold amount, they will explode suddenly. This is due to nonlinear nature of the differential equations commonly used to model.

Don't try to BS me, Leongsam

If you're trained in statistics you'll surely notice that there is no statistically significant difference between mask mandates and no mask mandates. eg North vs South Dakota.

I was in QA for many years during my corporate life and statistics was used to determine which process and materials were better than others. It was there that I learned that data obtained during an engineering evaluation run often did not hold up when it came to a production run of hundreds of thousands of units simply because there were so many more variables at play on the production floor vs the engineering lab.

I'm not anti mask in fact when I have a head cold I put on a mask at home to reduce the chances of other household members catching the bug.

However I cannot help but notice that all the theoretical advantages of wearing a mask do not seem to translate into any difference in the real world.

My theory is that the vast majority of Covid transmission is via aerosols rather than droplets because aerosols is what you breath in especially in confined spaces. Droplets are not inhaled. They can land on you but that alone does not cause transmission as Covid is not transmitted through the skin.

Aerosols also enter the eyes which has ducts which drain into the nasal cavities so covering nose and mouth without eye protection does not do much. If you walk into a smokey area and your eyes sting that's because tiny particles are irritating the cornea. Covid is no different.

That's my analysis. Of course I may be wrong in my conclusion but the data is there for all to see and too interpret in any way they want.

As always I'm here to play the role of the contrarian and all intelligent debate is welcome. Memes as responses do nothing because they're politically rather than scientifically motivated but an explanation as to why the stats show no advantages from masking up are great.

 

[Kraken]

If you're trained in statistics you'll surely notice that there is no statistically significant difference between mask mandates and no mask mandates. eg North vs South Dakota.

I was in QA for many years during my corporate life and statistics was used to determine which process and materials were better than others. It was there that I learned that data obtained during an engineering evaluation run often did not hold up when it came to a production run of hundreds of thousands of units simply because there were so many more variables at play on the production floor vs the engineering lab.

I'm not anti mask in fact when I have a head cold I put on a mask at home to reduce the chances of other household members catching the bug.

However I cannot help but notice that all the theoretical advantages of wearing a mask do not seem to translate into any difference in the real world.

My theory is that the vast majority of Covid transmission is via aerosols rather than droplets because aerosols is what you breath in especially in confined spaces. Droplets are not inhaled. They can land on you but that alone does not cause transmission as Covid is not transmitted through the skin.

Aerosols also enter the eyes which has ducts which drain into the nasal cavities so covering nose and mouth without eye protection does not do much. If you walk into a smokey area and your eyes sting that's because tiny particles are irritating the cornea. Covid is no different.

That's my analysis. Of course I may be wrong in my conclusion but the data is there for all to see and too interpret in any way they want.

As always I'm here to play the role of the contrarian and all intelligent debate is welcome. Memes as responses do nothing because they're politically rather than scientifically motivated but an explanation as to why the stats show no advantages from masking up are great.

HA HA you look like fool once again. Now many time you r like those poor thing. Wear mask. Mask very effective, very nice. US CDC say wear 2, can cut down by 95%

 

[Leongsam]

This makes a lot of sense because droplets can enter the eyes. In my opinion wearing eye protection would do a lot more than wearing a mask.

Covid 19 coronavirus: People who wear glasses 'less likely' to catch virus
NZ Herald

2-3 minutes

Website of the Year
Lifestyle
26 Feb, 2021 04:56 PM2 minutes to read

Sick of foggy lenses with your face mask? We've got some good news for you. Photo / Getty Images

Foggy lens are an annoying side-effect of the glasses and face mask combo but, if a new study is anything to go by, there might be a rewarding payoff.
People who wear glasses are less likely to contract coronavirus, a new study has found.

The study is the latest in a series of studies regarding Covid-19 and wearing glasses, showing that those who need spectacles may be less exposed to the virus, compared to those who don't wear glasses.

"If something lands in your eye, it can go through a duct that goes down into your nose and that's how it might infect you," Professor Yanneer Bar-Yam, of The New England Complex Systems Institute said, explaining how people who do not wear glasses are more exposed to the virus.

In the study, published this month in India, 304 Covid-19 patients were analysed. It found only 19 per cent of those infected with coronavirus wore glasses.

In India, about 40 per cent of the population wear glasses.

The study concluded that "the risk of Covid-19 was about two to three times less in the spectacles-wearing population than the population not wearing them".

"Probably one of the main pieces is that the air particles will get deposited on your glasses as well as you might not touch your eyes a little bit, but it's really important to know that this is in addition to wearing a mask," Professor Bar-Yam said.

According to the expert, the latest study mirrors a previous study conducted in China.

However, researchers warn that glasses are not "fool-proof protection" and goggles are even better when it comes to preventing any particle from reaching the eyes.
The expert also warns that people who wear glasses and may have visited places where they could have been exposed to the virus should wash the spectacles thoroughly as the virus particles can become lodged in the glasses.

 

[Leongsam]

HA HA you look like fool once again. Now many time you r like those poor thing. Wear mask. Mask very effective, very nice. US CDC say wear 2, can cut down by 95%

View attachment 105560

I'm trying to have a proper discussion here so please do not post your stupid memes in this thread. Let's keep it logical.

If masks cut transmission the data would bear this out.

 

[Kraken]

I'm trying to have a proper discussion here so please do not post your stupid memes in this thread. Let's keep it logical.

If masks cut transmission the data would bear this out.

You are exposed liar and cheat. Ur post is fake and figure is made up. Wear mask,. Mask is nice, good for you.

Mask help many city recover from Pandemic.

 

[capamerica]

You are exposed liar and cheat. Ur post is fake and figure is made up. Wear mask,. Mask is nice, good for you.

Mask help many city recover from Pandemic.

View attachment 105566

Yes, we know masks work

 

[Vlad Tepes]

I am gonna tell you for the last time. Unless you are paying for every Singaporean's fine attached for not wearing mask. You can start with me, send me a 20 K sgd (in case i need a good lawyer), then I'II go around without a mask. Will pm you my PP email, if you're so devoted to your erhm "cause". Also, please kindly write in to MOH with the data you posted. Posting here is pretty much useless. I am not sure what you're trying to achieve here. But for such childish antics, you would actually be the last person I expect. Alas, you prove me wrong.

If you're expecting everyday Singaporean to rise up and overthrow PAP. That would perhaps be in your next lifetime.

 

[Scrooball (clone)]

So far, most studies found little to no evidence for the effectiveness of cloth face masks in the general population,

Very sneaky to make a general statement that points to just ‘CLOTH’ face masks.

 

[SalahParking]

prolonged masking increase rebreathing of yourown CO2. It reduces your immunity and less likely to repel the virus

 

[laksaboy]

They are very effective for raking in money for various vested interests.

 

[Vlad Tepes]

prolonged masking increase rebreathing of yourown CO2. It reduces your immunity and less likely to repel the virus

Says who?

 

[tanwahtiu]

View attachment 105555

Fuck him lah. Blowing out smoke is not the same as virus. What an idiot like u believe him.