Leading infectious disease expert Dr. Michael Osterholm said cloth or surgical masks "protect very little" on MSNBC recently.
One expert somewhat disagrees with Dr. Osterholm. Oxford University's Dr. Trisha Greenhalgh said wearing cloth masks helps reduce the transmission rate of the Covid-19 virus in an article published in the Journal of Evaluation of Clinical Practice:
In relation to a community‐wide intervention such as face coverings, we do not need to prevent every transmission of every droplet or every viral particle. As with hand‐washing and social distancing, the objective of the policy is more modest: to achieve a substantial reduction in the transmission rate of the virus. Every infectious disease has a transmission rate (R0). A disease with an R0 of 1.0 means that each infected person, on average, infects one other person. A disease whose R0 is less than 1.0 will die out. The strain of flu that caused the 1918 pandemic had an R0 of 1.8. The R0 of Sars‐CoV‐2 was estimated at 2.4 by Imperial College researchers,24 and other research suggests it could even higher.25 A population measure that reduces the transmission rate (“effective R0” or Reff) to below 1.0 will be highly effective, even if some cases of transmission still occur .To mask or not to mask. It is an interesting question on which the scientists don't agree. Meanwhile, we can hope we don't see any more scenes such as what recently took place in New York City (of course):
Mathematical modelling suggests that a face covering that is 60% effective at blocking viral transmission and is worn by 60% of the population will reduce R0 to below 1.0.26 This leaves plenty of room for error as people make their own imperfect coverings from old clothing and as some people either cannot or will not wear a face covering. Not all respiratory viruses are filtered equally; masks appear to be more efficient at blocking Sars‐Cov‐2 than rhinoviruses or adenoviruses, for example.27 Materials scientists have shown that whilst different fabrics are more or less efficient at blocking particle transmission, cotton weaves with high thread count or a double layer of two different fabrics (eg, cotton‐flannel) typically provides high filtration efficiency.28
There are now many natural experiments of the wearing of masks or face coverings in Covid‐19, as countries introduce either mandatory or voluntary policies. Of note is the example of the Czech Republic and Austria, both of which introduced social distancing on the same day; the former also introduced compulsory face coverings. New covid‐19 infections fell more quickly in the Czech Republic, and only began to fall in Austria after masks were made mandatory 2 weeks later,3 though an alternative interpretation of this natural experiment is that Austrian data was confounded by changes in testing policy.29 Also noteworthy is the observation that every single country where masks or cloth face coverings have been introduced as national policy (often but not always alongside other measures), rates of transmission fell in the subsequent days....
There is no reason why the public should wear medical‐grade masks, since cotton face coverings are more comfortable, recyclable, and sufficiently effective for source control, especially given the evidence on how this particular virus behaves (it sits in the upper respiratory tract and is emitted mostly in droplets)... Rest of article.
35 comments:
If I had the choice of being forced to wear a mask to keep the economy open, and sitting at home watching cable news all day, I would choose the mask.
The mask only helps if everyone wears them properly.
Masks help a little but social distances are what you can really count on. Masks give a false sense of security which leads to you dropping your guard down and getting close to people.
"forced"?
What country do you live in?
...but that's not the choice.
Quarantine is when you restrict the movement of sick people.
Tyranny is when you restrict the movement of healthy people.
When it comes to getting sick, I'd rather err on the side of caution.
Mask on.
What I heard was the same tired argument that masks don't protect 100% so don't worry about them. Of course if you stand two feet from an infected person and engage in an extended conversation the likelihood of getting infected is high regardless if you or they are wearing a mask. Heck, he makes a great argument for continued closing of gyms and salons.
Masks are not a replacement for social distancing. They are an important tool to prevent the community spread of the virus. Dr. Scott Guthrie of the IHME said the use of masks by infected people reduced the transmission rate by about 50%. That is a huge reduction. All you have to do is look at hospitals to see the general acceptance that masks work. If they were so ineffective why do doctors, nurses, dentists, etc. all wear one when they are working on someone with an open wound or incision? It's because they do protect the patient and have been proven to reduce secondary infections.
@9:26 didn't read the post before putting in comments. "The mask only helps if everyone wears them properly." That is not what the post states.
Thanks for putting this information up, Kingfish. Most blog sites and Twitter accounts are so polarized that the "maskers" and the "non-maskers" don't try to communicate or look to see where the truth may reside.
It is clear from the bloggers here and elsewhere that there is no tolerance for further "shelter in place" even if it would protect more people. The economy is wrecked and needs to recover.
What we should seek is respect for each other. Avoidance of crowds. Avoidance of closed spaces for long periods of time. Avoidance of close physical contact. "Social distancing" is wrong. We need social bonding and respect for the vulnerable who will need special accommodation as everything is opened.
Problem is many people with pre existing conditions need those gyms to stay healthy. It's almost a catch 22.
In answer to the question posed by the headline, the article answers "YES." That is if a majority wear them correctly. We're doomed.
Masks are a joke and how do we know that the viral particles fall to the floor at 5'11" inches? I see that the CDC is flip flopping again.
https://www.salon.com/2020/05/25/cdc-revises-its-guidelines-on-surface-contact-prompting-an-outbreak-of-misleading-headlines/
If you watch the video, Dr. Osterholm agrees with the CDC.
See that CDC has flip flopped again. Wonder how a virus knows to stop traveling at 5'11" inches and drop to the floor? Inquiring minds want to know.
I guess i need to go back to wearing my 3M P100 halfmask respirator and goggles. Idgaf if you call me a tool.
Nobody is using any PPE correctly, a quick trip the the grocery store takes no less than three pairs of gloves and a few masks to provide the protection they THINK they are getting; further, it takes real discipline when one migrates from a "clean" zone to a "contaminated" zone. What I see (and have seen) is mask enthusiasts seeking any and every opportunity to lecture those of us who choose not wear masks.
Last week, my wife was accosted by some twenty-something in Kroger who saw fit to lecture her on how irresponsible it was for her to be out and about with no protection. I was the next aisle over, heard the commotion and went to see what the problem was - what I saw was an angry young woman screaming at my wife (with her mask pulled down), and my wife with a look of disbelief on her face. My wife and I are both federal agents and thought we had seen everything, but this is ridiculous...we let the mask enthusiast vent, politely said thanks and walked out of the store shaking our heads.
No particular reason you can’t social distance at the gym. As long as the gym doesn’t allow too many people in at one time, it isn’t that hard. I have been social distancing at the gym since it reopened. Not really a problem,
10:22 Nothing in life is 100%. Do you think a car crash is somehow 100% survivable at 55MPH but is instantly fatal at 56MPH. Of course not, the severity depends on a lot more than just the speed.
Same thing with surface contact with the virus. It is possible to get it from touching an infected surface, but the likelihood of contracting the disease that way is still being refined. You go with what you know from other similar diseases and then adjust based on actual experience. COVID-19 is apparently less transmissible than the average virus, but it is still a danger. I wouldn't go touching canned goods in Walmart and then wiping my eyes or nose. On the other hand, I'm not going to sanitize my mail that has been sitting in the box for six hours either.
Same thing with airborne particles. There isn't a magical barrier at 6 feet where you are suddenly 100% protected. However, based on evidence the likelihood of infection falls off significantly at 6 feet. A violent cough or sneeze by an unmasked person could certainly cause a virally dense enough cloud at up to 25 feet to infect a person under the right conditions. Being in long-term exposure in an enclosed environment can cause infection at even longer distances as shown by the super-spreading events at churches.
It's all about relative chance though. The recommendations are based on data known at the time that shows where the likelihood drops significantly, not where it is reduced to zero.
Masks are worn by sick people to keep them from spreading disease. Healthy people do not need masks. I am healthy and choose not to wear a mask. If I see some people wearing a mask coming at me I am going to assume they are sick people and make sure they do not come close to me.
People may think a mask protects them. If they decide to attack another person they will soon learn a mask does not stop a bullet.
KF, there are ways to exercise without going to a gym. If the comments here reflect the views of most Mississippians, there will be a surge of new cases and deaths.
Funny that doctors have been recommending vulnerable or immune compromised individuals wear a mask for years, and now, it’s a political
Issue that asks everyone from celebrity athletes to dumb politicians to weigh in.
Wear a mask. It’s not going to hurt you.
10:39 The problem is that with COVID-19 you have an 85% chance of being able to spread the virus without knowing you are sick. Better than half the infected people never have symptoms severe enough to indicate a COVID infection and even those that do typically don't experience them until two or three days after becoming infectious.
You make the absolute, unequivocal statement that you are healthy when the reality is you cannot say so with certainty.
Maybe God created Covid-19 to rid us of the selfish and the stupid? Unfortunately there will be collateral damage.
"We know that wearing a mask outside health care facilities offers little, if any, protection from infection. Public health authorities define a significant exposure to Covid-19 as face-to-face contact within 6 feet with a patient with symptomatic Covid-19 that is sustained for at least a few minutes (and some say more than 10 minutes or even 30 minutes). The chance of catching Covid-19 from a passing interaction in a public space is therefore minimal. In many cases, the desire for widespread masking is a reflexive reaction to anxiety over the pandemic." https://www.nejm.org/doi/full/10.1056/NEJMp2006372?fbclid=IwAR1EoJkVn0xxmfBb6RNhasEb2XXM6E2Lr-p7YOMrvMFl9iMBwKPQLl96lIo
if we look to countries that have significantly reduced their case rate--theres a common theme. mask wearing. it helps reduce the spread by people who don't know they have it..and all evidence is now saying there's a lot more people who have/had it and had no symptoms whatsoever. So, science shows that wearing a mask reduces your chance of spreading it. You may have it and never know you did but you could give it to someone who ends up in the hospital. Pray about that one..
In January, we knew almost nothing about this. Thanks to ongoing research, we know a lot more about it and how to help those have a chance if they have to go to the hospital. Knowledge and research lead to change. We are researching Covid-19. Official medical and professional opinions WILL CHANGE as a result and it has nothing to do with politics.
Covid 19 does not care one bit if you are a Democrat, Republican, Libertarian, Communist, Christian, Buddhist, or Agnostic.
No 11:45am....it is killing the weak. Intelligence has nothing to do with it.
Nearly everything related to PPE use and efficacy, virus transmissibility and contagion, and symptoms has changed (and continues to change) since this whole rodeo started.
I honestly don't think anyone in a leadership role has enough information to drive informed, smart decisions for responding agencies or to provide advice for the general public.
If you are sick or in a high-risk group, stay home, if you are healthy, take appropriate precautions and go on with your life.
Thank you at 11:55. That link is very informative. My question would be: if this was known at the first of April why was the silly use of a mask push, even by some now? No, I am not questioning the validity of the article, but I do question the narrative forced down the throats of the American people. That narrative being if a mask is not worn in public the non-wearer is to be anathema, excommunicated from the human race. All this narrative has accomplished is the revealing of the Karens among us. Brother, there are many. You have to look no further than this comment section to see the proof of this. Face the facts, we live in a world filled with risk.
Well, click the link and read the full article I posted. She makes a credible case for wearing masks as well.
12:21 - correlation is not causation, can you prove with scientific certainty that other variables are not at play?
@2:21 p.m. - What type of opinion do you call that of the CDC's on masks in March?
Was there a poll taken to determine the number of scientists in each group? Is that how this works now? Or as one poster called it a "consensus", following along the lines of global warming or climate change whichever wordplay that they choose to use. From where I sit the left-leaning politicians and the mainstream news media, which appear to be one and the same, determined early on to make this more than it was. Was it a problem? Yes, but not to the level it was hyped. Every molehill becomes a mountain with enough dirt placed on it.
The argument for masks is not that it protects the wearer. It protects other people if you have COVID and are an asymptomatic carrier. The doctor's comments regarding minutes-long conversations does not apply to people passing by each other in aisles in the grocery store or on the sidewalk. Simply, he says nothing that negates the near-unanimous message from the medical community that wearing a mask during these times helps to protects others from unnecessary risks.
That being said, here's a pros and cons list to wearing a mask:
Pro: you protect others from getting sick (potentially the sickest they've ever been) and/or dying; it entails no orders from any government restricting your movement; it costs very little money to get one and no money to wear; it takes virtually no time to put on.
Con: you might feel silly wearing it.
Yep -- given the balance of interests there, I will assume you are selfish and will treat you as if you "have a disease" as the doctor put it on TV. No apologies.
2:26 asked 12:21 to provide some evidence that masks have an effect on virus transmission. I'm not 12:21, but if I may give it a shot:
1. I think all sensible people, doctor or otherwise, can all agree that this virus is transmitted primarily but not exclusively by exhalation shedding and contracted by inhalation as the primary but not the only route of infection.
2. We know the size of the virus.
For those that can agree with these basically undisputed points, get something about the size of a golf ball or a quarter and a DVD or a .5 liter water or soda bottle. Now, put the golf ball or quarter through the hole in the DVD or into the opening of the bottle. Can't do it? Of course not, because the ball or coin is larger than the opening. Since a N95 respirator is specifically designed so that its "openings" are too small for something the size of this virus to go through, it cannot do so. Therefore, if there is a N95 between your mouth and nose and this virus, it cannot get from the outside of the N95 to your respiratory system. So, I would submit that reasonable people can agree that a N95 will prevent the passage of viruses too large to go through and if it is properly fitted to the face, viruses cannot "go around."
As to "masks," a visualization isn't so straight-forward because of the myriad "masks" out there and the wide size range of the "openings." But here's something to consider. Imagine a coffee filter - the large grounds and nearly all of the "dust" remain in the filter, but the water extracts various molecules and chemicals, which drain into the carafe. So if the "openings" in the material of the mask are, like the N95, smaller than the virus, it cannot pass. But even if the "openings" are slightly larger than the virus, it can still help. Imagine a basketball and hoop. The ball can pass through but if the ball hits the rim it often bounces away. Yes, this is a less-than-perfect system to _prevent_ virus transmission, but if the hoop were a mile across (your mouth) something as relatively tiny to it as a basketball (the virus) would make it through every time with absolutely nothing to stop it. Now imagine a million golf balls hit at a chain link fence. Yes, some number will go through, but a lot will hit the fence and not make it. With viruses, the number that make it through does matter. The fewer that make it, the less chance of infection as well as the less severe an infection will likely be.
But wait, there's more! The respiratory droplets that serve as carriers of the virus from the infected person to others are much larger than the virus itself, so if you can "catch" the droplets, you stop them from entering the airways of others. For that, imagine a molded jello with fruit cocktail in it. Even if you turn it out of the mold onto a rack with a mesh size that the fruit cocktail could pass through if weren't trapped in the jello, the jello prevents it from doing so unless you force it through the mesh.
Admittedly, these aren't completely perfect examples and there are other factors to consider, but they are accurate enough for the average person to understand the broad concept of how and why N95s and masks can prevent or at least mitigate transmission of this virus.
@5:08, 2:21PM responding. If you mean the official CDC "guidance," I'd call it "lacking"...or perhaps "covfefe."
If you mean a particular opinion, especially private ones, by a particular person at the CDC, based on those I've heard or read it would range from "dead wrong" to "totally correct." But that said it's a government agency with all the baggage that entails so that's generally true about every situation in which such agencies are involved. And I don't think you'd find that is a unique POV...assuming you don't already know that.
"The problem is that with COVID-19 you have an 85% chance of being able to spread the virus without knowing you are sick. Better than half the infected people never have symptoms severe enough to indicate a COVID infection"
And of those who do... the vast majority are elderly, or have infirmities, or both.
It's almost as if some Communist government realized that decades upon decades of a "One Child" policy had created an massive proportion of elderly citizens that consume an unacceptable level of resources from the smaller working population.
Could it be that a highly infectious virus that targets the elderly and infirm might 'accidentally' escape the Institute of Virulogy in Wuhan, that would leave the valuable working population relatively unscathed?
Naw! Impossible.
History has shown communist governments to be honest, caring, and valuing all human life.
My tinfoil hat must be askew.
Carry on.
Actually we know that a virus travels up to 6ft in winter time and that distance actually falls to about 2ft during the summer time.
There's a reason Winter is flu and cold season and why Summer is not.
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