The easy to point to example is how a lot of doctors viewed masks at the beginning of the pandemic. Or how trickle down economics is also endorsed by experts. Or experts opinions on mental health drugs. And so many other subjects where it won’t be hard to find an expert on the dumb side of the argument.
I think we should rely on experts, but we can’t dismiss people’s doubts or research just with a “I’ve seen a real doctor” slight of hand.
Ok, so I've looked into the history of this a little, and most of the mask mythology seems misunderstood.
Prior to 2020, most medical professionals believed most viruses, and corona viruses particularly, could not be transported as aerosols. This was a subject of research where the data had not come in.
About late March, it began to appear that the virus could be an aerosol. Hard results did not come in until April and May, and many in the field discovered they had egg on their faces.
Conflicting advice is to be expected with new information.
Example, a local wine shop in my small town where you are not allowed to touch the bottles, but I see the staff inside with their masks off when there's no customers in the store.
Frankly, I think people really just don't _want_ to believe it's aerosol transmitted. Because the consequences for public policy would be so drastic; no malls, no factories, no schools, etc. should really be open if you admit it.
But it’s also possible they’d have to admit grandma-type adages about opening the windows actually work and office buildings don’t let you do this anymore.
But no, keep applying youre second grade logic: spreads through air-> indoor places unsafe-> CLOSE EVERYTHING.
That's not to say some of it isn't security theater (ie my parents were washing cookie boxes with soap some a couple of months ago), but those measures aren't being driven by the public health, but rather the unrelenting fear mongering of the media.
I've also looked into it a little and come to the opposite conclusion. Here is one study from Singapore in 2014 that showed surgical and n95 have about a 68% and 95% efficacy respectively at preventing SARS transmission https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4293989/ Masks have also been shown to provide protection against the common cold (many strains of which are also coronaviruses) and seasonal flus https://www.livescience.com/7661-masks-protect-colds-flu.htm...
In the absence of more specific information about SARS-COV-2 early in the pandemic, surely it would have made sense to default to using the preventative measures that were known to be effective at controlling SARS and other known respiratory diseases? Especially when these measures come with no real risks.
It's true that they didn't know with 100% certainty, and China's misinformation about human to human spread in the beginning and not allowing the CDC team in early to investigate certainly didn't help either. Maybe these experts, including Dr Fauci, the CDC, and WHO, just made what turned out to be very bad judgement calls and they honestly thought that masks wouldn't prevent the spread of the disease. But by far the likeliest explanation in my mind is that these institutions knowingly lied to the public in an attempt to manipulate people into not buying masks, and I still find that to be absolutely unconscionable.
https://bmcinfectdis.biomedcentral.com/articles/10.1186/s128... [2019]
"In summary, despite the various mechanistic arguments about which organisms can be potentially airborne and therefore aerosol-transmissible, ultimately, the main deciding factor appears to be how many studies using various differing approaches: empirical (clinical, epidemiological), and/or experimental (e.g. using animal models), and/or mechanistic (using airflow tracers and air-sampling) methods, reach the same consensus opinion. Over time, the scientific community will eventually form an impression of the predominant transmission route for that specific agent, even if the conclusion is one of mixed transmission routes, with different routes predominating depending on the specific situations. This is the case for influenza viruses, and is likely the most realistic."
The link I posted is to a 2019 paper discussing how and why some viruses are considered airborne transmissible such that masks would help. (Single papers don't usually settle complex questions, right?)
cactus2093's links are to a paper discussing the difficulty of getting people to use masks correctly and a science popularization article describing an unnamed study from the University of New South Wales and an unidentified CDC study. The first link does include references about the utility of masks, to articles titled "Risk of transmission of airborne infection during train commute based on mathematical model", "Knowledge about pandemic influenza and compliance with containment measures among Australians", "Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review", "Professional and home-made face masks reduce exposure to respiratory infections among the general population", and "A schlieren optical study of the human cough with and without wearing masks for aerosol infection control", but those don't seem to imply the issue is settled. The second link does go on to say, "While some governments are already stockpiling masks for use in emergencies, MacIntyre said these guidelines had been implemented without evidence to support them. "We now have provided that evidence," she said," but it's difficult to evaluate the last sentence.
> Prior to 2020, most medical professionals believed most viruses, and corona viruses particularly, could not be transported as aerosols. This was a subject of research where the data had not come in.
cactus2093 replied
> I've also looked into it a little and come to the opposite conclusion. Here is one study from Singapore in 2014 that showed surgical and n95 have about a 68% and 95% efficacy respectively at preventing SARS transmission https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4293989/ Masks have also been shown to provide protection against the common cold (many strains of which are also coronaviruses) and seasonal flus https://www.livescience.com/7661-masks-protect-colds-flu.htm...
There's two ways I can see you interpreting this.
1) You are being extremely narrow in your focus and saying that you are talking specifically about viruses being transmitted as aerosols (although the overarching topic here is about whether or not masks are effective). And thus, since there was no research specifically about this, then there's no reason to recommend masks. This doesn't address the point that there's research that shows masks are effective against similar kinds of viruses.
2) You actually are talking about effectiveness of masks and saying that viruses could not be transmitted via aerosol was to say that because they are not shown to be transmitted via aerosol, then there's no evidence that masks would work, in which case, again, we're back to the issue that there was research prior to 2020 that showed masks are effective against similar kinds of viruses.
So the question remains, are you wrong about your assertion that
> Prior to 2020, most medical professionals believed most viruses, and corona viruses particularly, could not be transported as aerosols. This was a subject of research where the data had not come in.
and if not, what are we missing about what you're trying to say?
> Some kind of admission that the US health field ignored research because "eww, icky Asians?"
There was certainly the perception that Asians wearing masks was ridiculous. Whether or not this perception extended to American experts and influenced their conclusions is unknown to me.
"1) You are being extremely narrow in your focus and saying that you are talking specifically about viruses being transmitted as aerosols (although the overarching topic here is about whether or not masks are effective). And thus, since there was no research specifically about this, then there's no reason to recommend masks. This doesn't address the point that there's research that shows masks are effective against similar kinds of viruses.
"2) You actually are talking about effectiveness of masks and saying that viruses could not be transmitted via aerosol was to say that because they are not shown to be transmitted via aerosol, then there's no evidence that masks would work, in which case, again, we're back to the issue that there was research prior to 2020 that showed masks are effective against similar kinds of viruses."
Backing up a bit...
As far as I've seen, there are three primary routes for infection for respiratory diseases: 1) contaminated surfaces, 2) (large) droplets produced mostly by coughing or sneezing, and 3) (small) aerosol particles produced by normal activities like breathing and speaking.
The normal measures against 1) are avoiding touching possibly contaminated surfaces, washing your hands, and not touching your eyes, mouth, etc. And roughly speaking, that's about all you can do.
The normal measures against 2) are staying distant (i.e. 6ft) and keeping interactions short because the droplets do not remain airborne long, and covering your face when you cough or sneeze. Masks would certainly be helpful in the case of 2), but not especially so because a) the normal measures work fairly well, b) most people do not want to wear a mask[1], c) many people who do wear a mask do not do so correctly, and d) the supplies of medical grade masks were (are?) sketchy. (Both of the links provided are specifically aimed at b) and c), no?)[2] A study of 1000 students at an Australian university is interesting, but the advantage of a) don't necessarily overwhelm b), c), and d).
There are no normal measures against 3). The only useful measures are to avoid all contact with potential carriers, significantly improve indoor ventilation and air filtration (aerosols remain airborne for a very long time), and properly using medically-effective masks when interactions are required. Transmission by asymptomatic carriers is primary, hard epidemiological evidence of 3).
According to (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7322154/), asymptomatic carriers were reported at the end of January and significant confirmation appeared about March (https://wwwnc.cdc.gov/eid/article/26/7/20-1595_article). Shortly after that (April 3), the CDC recommended masks (https://www.bmj.com/content/369/bmj.m1422).
From your limited choices, my closest meaning is your 1). But,....
Now, put yourself in the place of someone making an official policy recommendation in, say, February or early March. You don't have hard evidence that masks are required, but you do understand that they will provide some marginal benefit. On the other hand, ensuring that masks are worn consistently and correctly is an uphill struggle (as we have seen over the last year). Further, the supply of medical grade masks where their use is required, hospitals for example, is not infinite. Oh, and you want to make the minimally invasive recommendation you can, because you actually aren't out to cause as much damage as possible by, say, killing the economy. Beyond that, you know that at some point you are going to be facing pandemic fatigue, where people stop taking the situation seriously and then things get very bad (as in last summer, last fall, and earlier this winter). What do you do?
As it turns out, they were wrong about some of their assumptions. Being wrong happens. It is not proof of an evil conspiracy or even of a conspiracy of stupidity. It's people who are pretty good at what they do, making what they think are the best choices, and being wrong.
Suggested Reading
https://www.bmj.com/content/369/bmj.m1422
https://news.ycombinator.com/item?id=25616014 (No, really, "The Plague Year" in the New Yorker is probably the best history of the pandemic so far, and explicitly touches on a lot of these issues---including medical professionals saying, "yeah, we were wrong.")
[1] I am talking about the US specifically, not Taiwan, Japan, or anywhere where mask wearing is more common socially.
[2] Everyone wearing pressurized, highly filtered contamination suits at all times would prevent essentially all cases of respiratory disease transmission. But no one is going to push that idea without a really, really good reason.
PS: While writing this, I ran across https://www.sciencedirect.com/science/article/pii/S019665532..., which is the first solid, halfway data-backed estimate of the prevalence of asymptomatic carriers: 1.82%
As I remember it, the advice wasn't "don't wear masks," the advice was "stay home." If they said "go buy masks," that would mean leaving your house to get a mask, which would directly contradict the more important advice of staying home. Also if they said wear a mask when you leave the house it would have been interpreted as "it's ok to go on with normal events as long as we have masks" which wasn't the message they were trying to send, either. The message was stay home, and at the time it was probably the right message, and not a lie.
There was “stay home” but also “stop buying masks because you are stopping medical, first responder, etc. personnel from getting them and they aren't useful for the general public” during the initial PPE supply shortage and hoarding.
This wasn't a lie, AFAICT, but Aa statement that was completely correct public health statement in the context it was given that was widely interpreted as an individual health statement.
There was no misunderstanding, the message was "don't wear a mask unless you're sick, masks don't help the wearer they only help keep a sick person from spreading it to others around them". That was just a lie at the time, we didn't know that for sure and we had every reason to suspect the opposite.
I've heard lots of people say that was the message, but it wasn't the one I heard and it's not the one I find in any of the documented statements from public health officials.
That’s most American medical professionals. And they mostly seemed to believe you would get yourself sick faster by touching your eyes after taking the mask off wrong, or that masks provided 0% protection unless you wore an N95 with a fit test, or that if they didn’t lie about them being useless people would steal them from hospitals. They certainly didn’t believe they were truly useless, since they were all wearing them for procedures.
Actually, wasn’t the excuse for suddenly being like “face masks are good actually” that they didn’t know COVID had asymptomatic spread before then? That’s even worse than not knowing it spread through aerosols.
> This was a subject of research where the data had not come in.
By using the technique of “not assuming all of Asia is primitive and superstitious”, it was easy to figure out what to do without an RCT. Note there isn’t evidence that surgical masks help during surgery either.
My company had a zoom conference with a very well respected British doctor, he won something more or less equivalent to a nobel prize in mediciine, and he told my company, on May 4th, that masks are not necessary. This was already a bit head scratching, but what I feel he probably meant, but certainly did not explicitly say- is that its not a priority for an individual to wear a mask when there are shortages for front line workers.
But mix a changing message with an inbred resistance to being told what to do and the inconvenience of a mask, and this comes out the end for many as "They don't know what they are talking about these "experts!", I don't need to listen to them, they can't get their story straight!" and here we are...
This comes off as blatantly lying to us for our harm, not "they don't know what they're talking about". If someone lies to you and knowingly puts your life at risk through the lie, it's very rational not to believe anything they say in the future. This is not mere mixed messages.
If government and/or experts want to have non-negative credibility, they are going to have to start consistently telling the whole truth.
Exactly. Real life example - someone I know asked her doctor about getting the Moderna covid vaccine while pregnant. The doctor not only said it was ok, but also verbally recommended it and gave her a written paper to help her get the vaccine. She was able to get it a couple days ago. Then yesterday the World Health Organization announced that pregnant women should not be getting the Moderna vaccine because they were not included in the trials.
So who’s right here? It’s hard to trust a “real doctor” when something like this happens.
It also happens that, doctors in particular, barely see you for 5-15min, that is not enough time for them to fully understand what is going on with you and your whole history. It’s only enough time for them to make a quick judgement based on their pattern matching abilities from their own experience and then give, an educated, recommendation. But they are not really vested in you in particular, you are just one more, and if their recommendations don’t work for you, they usually don’t really care and won’t go down the rabbit whole with you, at the most they’ll just refer you to someone else.
A doctor usually looks at an individual. (And we know a lot of pregnant women got infected with COVID. We know that hospitalization was higher for them, but also that mortality is the same - https://www.cdc.gov/mmwr/volumes/69/wr/mm6925a1.htm?s_cid=mm... , so the immune reaction should be the same too)
The real problem is that it's impossible for a non-expert to gauge the expertise of any of these entities (your full-sized real-life walking-talking doctor who you know for a deacade, the WHO and anyone in between). Even simply asking many questions is just the illusion of getting informed (not just because there's rarely any time for proper answers as you mentioned), but because the answers are biased, so this naturally biases the next question too. (Unless there's enough time and effort to go through years of science and try to falsify whatever theory is being communicated with very targeted questions, it's close to useless/futile effort.)
> But they are not really vested in you in particular, you are just one more,
Yep. Agreed. Also usually primary care physicians are better at "bedside manner" and pattern matching than at real medical science. (Because it's not really their job to have 20 doctorates in every subfield of biology.)
Trickle-down economics is not explicitly endorsed by anyone, because it's a pejorative. That's like saying "totalitarianism is popular in some countries"; you might think those countries are totalitarian, but they don't.
What many on the left assume it means, is a sincere description of growth "raising the tide"; and how ridiculous an idea that is.
Of course the tide has risen to an unprecedented degree in human history both since the term "trickle down" was invented; and moreso, over the last 40 years.
The term was coined by Will Rogers about 90 years ago.
This is a side effect of using the same category terms, but not talking about the underlying distributions.
Eg., in the UK, 80% of the country were industrial working class or poorer until 1980s; and middle class only started at top 5%.
Today, the "industrial working class" level of wealth, is the bottom 20% at the very most.
So if you hold the class terms fixed, "middle class" it seems the 80s top 5% has "stagnated", only to fail to mention, it now 60% of the country.
If you hold the distributions constant, the wealth level acheived in the top 5% in 1980s is now a majority of the population.
"You" in the above is a specific individual.
"They" in the above is undefined and extremely imprecise.
For various definitions of "they", your statement could be true, false or somewhere in between.
I read the same waffling about masks you did, the information I read (since it was inconsistent) led me to believe that I should wear masks more than directed. I did this out of an abundance of caution because at the time early research eerily concluded that not much is known about the longer term effects of this virus, there was stark contrast in the symptoms various people had, and that there were layers to exercising prevention. I acted in a similar manner when I limited my social circle.
The difference in the way, I think, these people used much of the same information that I did is that it became authoritative to them. After they'd read enough articles straight from the CDC it made them feel qualified to interpret them. I'm reminded of one guy who demanded I get another PCR test before he hung out with me, even after I hadn't experienced a fever for 10+ days. For some context, when I got sick I came back negative on both tests I was given. I was later told my viral load was not high enough on those days, ironically these also happened to be some of the worst days of the virus. It was only after I lost taste and smell that the doctors realized I had COVID. My friend cited all the reading he had done as evidence that I just wouldn't accept his "perspective". When I asked the doctor about getting both PCR and an antibody test she responded, "Do you have an actual reason? We already knew you were sick." In reality, the time which I would've been contagious had long passed, yet my friend couldn't get it out of his mind that transmission was a possibility.
Another example is a friend whose brother had gotten COVID a few months back. His symptoms were certainly worse than mine. Where I didn't experience much trouble breathing, he did among other things. I went on a walk one day because it was one of the days in between being sick that I had some energy and wasn't overcome with brain fog. I shared that I was exhausted after this short walk and that I'd probably stave off a walk for a few days to see where I was at. She chastised me for going on a walk, explaining that her brother had been told not to exercise for three to six months, and that it seemed as if I was taking COVID as a joke. What I realized after googling this specific treatment plan is that it's usually given to people with some form of cardiomyopathy and other conditions (none of which I have.) I am now about 3 weeks removed from having COVID and I'm back to riding my bike, which is consistent with what my doctor told me. My doctor told me recovery has a lot of variables and I'll need to go at the pace that I'm comfortable with and listen to my body. Regular checkups should help to that end as well.
The theme among these people is when I tried to explain what doctors had told me and why I was going to stick to what they were saying (more generalized as drawing boundaries) I was met with harsh rejection. The key here is that authoritative sources were no longer respected. The fact of the matter is that doctors do take a bit to arrive at consensus and that can be frustrating to a public opinion that is waiting on them for their own sanity, but just because you landed on the correct conclusion a couple times (or even a more conservative solution that kept you equally safe) does not make you an authoritative source. So, I'm not going to tell people to stay in their own lane but you can't just go lecture people based on your own understanding. That's when you forget that all of this information you gather outside of your own domain is good for exercising caution and light conversation.
Yes, in general if you don't know much on a topic you'd on average do best if you listen to the experts but you can outperform that if you can identify the right kind of smart people with a good track record.
Of course they are right sometimes but on many issues with a binary choice (should or shouldn't wear masks) that's a 50% chance.
In the long run you want to be able to discern hearsay, opinion, and rumors from facts and accountability to them.
You see it today when inquiring if a pregnant woman should get the vaccine. Doctors won't really advise you because although they maybe feel it's totally safe if you're far enough along, they would be held accountable if something happened. They can be "pretty sure" about things, but that isn't enough. Meanwhile, "very smart person" on Twitter can reference a bunch of content from unaccountable people that says it's safe and come off as an expert when they aren't. It's easy to be "right" when you don't have skin in the game and especially so when no one is going to hold you to account for all the times you were wrong or misinformed.
That doctor didn't just avoid guessing. He gave unsolicited advice, on limited information, that turned out to be exactly wrong and somewhat dangerous.
No, but one doctor might base advice on one study he saw another on a different one. Having skin in the game helps but it is also well documented that doctors might be overly cautious due to risk of litigation and thus sometimes chose suboptimal courses of action.
>Of course they are right sometimes but on many issues with a binary choice (should or shouldn't wear masks) that's a 50% chance.
No, this isn't a real coinflip. There's evidence for and against things like this, and some people have learned better than others how to evaluate such evidence and can definitely do better than 50%.
Smart people with a good track record are generally called "the experts".
* There was preliminary evidence from the experts it might work.
* At some point Trump got wind of this and mentioned it.
* The media, in an effort to portray Trump as wrong, went on a crazy cherry-picking campaign to show HCQ as completely ineffective. "HCQ does not work" was the prevailing sentiment for almost the entire past year because of this, even though evidence was still coming out it does work under certain circumstances.
* Now that Trump is out of office, our understanding of HCQ is shifting back to exactly what that preliminary evidence said that Trump repeated.
"They included 30 569 patients with systemic lupus erythematosus or rheumatoid arthritis who were already taking hydroxychloroquine in the 6 months before what was considered as the start of the pandemic in England and 164 068 patients with these rheumatic diseases who did not use hydroxychloroquine. The study found no significant difference in standardised cumulative COVID-19 mortality associated with hydroxychloroquine use (0·23% among hydroxychloroquine users and 0·22% among non-users) with an adjusted hazard ratio of 1·03 (95% CI 0·80–1·33)."
* https://www.acc.org/latest-in-cardiology/clinical-trials/202...
"Among patients exposed to patients with SARS-CoV-2, hydroxychloroquine, administered within a median duration of 2 days as post-exposure prophylaxis, did not reduce the incidence of SARS-CoV-2 or COVID-19 infection within 14 days, compared with placebo (vitamin C)."
* https://www.nih.gov/news-events/nih-research-matters/hydroxy...
"Researchers assessed each patient’s condition 14 days after being assigned to a treatment group. They used a seven-category scale ranging from one (death) to seven (discharged from the hospital and able to perform normal activities). The results showed no significant difference between the hydroxychloroquine and placebo groups. The scientists also found no differences in any of 12 additional outcomes, which included mortality 28 days after assignment to a treatment group or time to recovery. Based on the data, they concluded that hydroxychloroquine was not an effective treatment."
* https://jamanetwork.com/journals/jama/fullarticle/2772921
"Several published rigorous studies have demonstrated similar findings. In the well-conducted clinical trials published to date, hydroxychloroquine has been evaluated in a wide variety of populations, ranging from patients with severe illness2-4 to individuals at risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, in whom the drug was used as primary prophylaxis5; these studies failed to show any beneficial effect of the drug. This raises the question: How did medicine get to the point where so many studies were conducted assessing the possible benefit of hydroxychloroquine, that led to nearly identical findings, and have been published in major journals?"
* https://www.nejm.org/doi/full/10.1056/NEJMoa2022926
"Among patients hospitalized with Covid-19, those who received hydroxychloroquine did not have a lower incidence of death at 28 days than those who received usual care."
* https://www.cdc.gov/mmwr/volumes/69/wr/mm6935a4.htm
"New prescriptions by specialists who did not typically prescribe these medications (defined as specialties accounting for ≤2% of new prescriptions before 2020) increased from 1,143 prescriptions in February 2020 to 75,569 in March 2020, an 80-fold increase from March 2019."
* https://www.aljazeera.com/economy/2021/1/27/oklahoma-attempt...
"Oklahoma tries to return $2m worth of hydroxychloroquine"
Under what circumstances does it work?
They primarily suffer from dogma IMHO. For example, now they know people with breathing difficulty should be kept in prone position. I dont know if that applies outside of Covid19, but I thought it was really interesting to see them learn it. Like "oh, what we'd normally do is bad but this variation is good".
Medicine also suffers from a fear (justified) of litigation. If they dont follow accepted practices they may get sued if someone dies. The funny thing with Covid was watching that fear when there was no accepted treatment. Seeing them say "The FDA hasn't approved that for covid" when they hadn't approved anything at all yet.
very US-centric. Medical litigation in many others parts of the world doesn't work in the same way, and isn't a driving force in the way medicine is practiced.
"When Knowledge Knows No Bounds: Self-Perceived Expertise Predicts Claims of Impossible Knowledge" - Stav Atir, Emily Rosenzweig, David Dunning
https://journals.sagepub.com/doi/abs/10.1177/095679761558819...
Sadly, many doctors and nurses are statistically illiterate. I know, because I (try to) teach them statistics. Remember, the Surgeon General of the CDC said that, "[masks] are NOT effective in preventing general public from catching #Coronavirus," perhaps in some misguided belief that avoiding panicked mask-buying was more important than a mask-wearing public.
[Sorry for insulting our healthcare heroes, but ... evidently y'all haven't been responsible for teaching them evidence-based medicine. It ain't easy.]
Use any definition of "mask" and "effective" you want, but preferably effective should include some concept of "prevents spread of respiratory disease".
Covid is a serious illness. Far too many people have been told, and believe, that they can continue their normal day to day life so long as they put mask on. This is untrue, and this advice has driven mass infection and death.
This spins off into a whole discussion of how evidence-based medicine can lead you off the cliff when you follow its letter, and not spirit, because despite something being bloody obvious, there is no RCT proving that.
“Parachute use to prevent death and major trauma related to gravitational challenge: systematic review of randomised controlled trials“
The argument was not "we can't do tests because this is new", the argument was "we've got dozens of studies across a range of settings and respiratory diseases (which we expect to act similarly to covid) and we struggle to see any benefit, until we drop the quality of the research down".
No, I can't. Can you link to papers that show flossing is effective? Probably not, but the mechanism is so obvious that essentially all dentists will tell you to floss. Further, mask-wearing was already a well-established practice in medical settings to prevent the spread of respiratory disease from practitioners to patients.
> believe that they can continue their normal day to day life so long as they put [a] mask on. This is untrue
Combined with some coordination on travel restrictions and quarantines, it seems Taiwan has been able to keep that normal day-to-day life for the majority of Taiwanese.
https://www.wbur.org/hereandnow/2021/01/08/taiwan-covid-19-p...
https://www.reuters.com/article/us-china-health-who/who-chie...
We don't see much benefit there, either. See the "clean surgery" papers.
That was a thing a few years back: https://www.health.harvard.edu/blog/tossing-flossing-2016081...
> We concluded that household use of face masks is associated with low adherence and is ineffective for controlling seasonal respiratory disease.
"Do masks work, if you use the right type of mask and wear it properly?" isn't particularly controversial (the answer is probably "yes") but it's a stupid question because we don't care about optimal use, we care about real world use. And in the real world people might improperly wear a mask and go outside when they're symptomatic.
We don't have much good quality evidence for that, but here's a study that showed people were prepared to do things like wear masks, but were less prepared to self-isolate or book a test if they had symptoms: https://www.medrxiv.org/content/10.1101/2020.09.15.20191957v...
"However, during a severe pandemic when use of face masks might be greater, pandemic transmission in households could be reduced."
Later: "Although our study suggests that community use of face masks is unlikely to be an effective control policy for seasonal respiratory diseases, adherent mask users had a significant reduction in the risk for clinical infection. [...] Adherence with treatments and preventive measures is well known to vary depending on perception of risk and would be expected to increase during an influenza pandemic. [...] Therefore, although we found that distributing masks during seasonal winter influenza outbreaks is an ineffective control measure characterized by low adherence, results indicate the potential efficacy of masks in contexts where a larger adherence may be expected, such as during a severe influenza pandemic or other emerging infection."
It was an open question, but the general opinion before 2020 was that masks would not be particularly useful. Sketchy results started appearing in March with better days in April and May. Several experts said, "we were wrong."
Medical grade masks are very useful. Others are less so. But they primarily prevent you from giving the virus to others.
https://old.reddit.com/r/Coronavirus/comments/fdf5fq/we_are_...
Here's a paper from 2010 after the H1N1 pandemic.
Face masks to prevent transmission of influenza virus: a systematic review https://www.cambridge.org/core/journals/epidemiology-and-inf...
Our review highlights the limited evidence base supporting the efficacy or effectiveness of face masks to reduce influenza virus transmission. An important concern when determining which public health interventions could be useful in mitigating local influenza virus epidemics, and which infection control procedures are necessary to prevent nosocomial transmission, is the mode of influenza virus transmission between people and in the environment.
The interesting thing is everything they recommend, we've adopted during COVID, including physical barriers and front line workers additional PPE equipment:
Physical barriers would be most effective in limiting short-distance transmission by direct or indirect contact and large droplet spread, while more comprehensive precautions would be required to prevent infection at longer distances via airborne spread of small (nuclei) droplet particles [19]. In healthcare settings, stringent precautions are recommended to protect against pathogens that are transmitted by the airborne route, including the use of N95-type respirators (which require fit testing), other personal protective equipment including gowns, gloves, head covers and face shields, and isolation of patients in negative-pressure rooms
There's five additional studies referenced in the MedPub doc: https://pubmed.ncbi.nlm.nih.gov/20092668/
A current Danish study concluded masks don't reduce the spread of the virus:
Effectiveness of Adding a Mask Recommendation to Other Public Health Measures to Prevent SARS-CoV-2 Infection in Danish Mask Wearers https://www.acpjournals.org/doi/10.7326/M20-6817
In this community-based, randomized controlled trial conducted in a setting where mask wearing was uncommon and was not among other recommended public health measures related to COVID-19, a recommendation to wear a surgical mask when outside the home among others did not reduce, at conventional levels of statistical significance, incident SARS-CoV-2 infection compared with no mask recommendation.
People are already debunking this Danish study but here's a CDC study showed even when people do wear masks, they were still getting sick:
Community and Close Contact Exposures Associated with COVID-19 Among Symptomatic Adults ≥18 Years in 11 Outpatient Health Care Facilities — United States, July 2020 https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6936a5-H.pdf
In the 14 days before illness onset, 71% of case-patients and 74% of control participants reported always using cloth face coverings or other mask types when in public,” the report stated.
In addition, over 14 percent of the case-patients said they “often” wore a face covering and were still infected with the virus. The study also demonstrates that under 4 percent of the case-patients became sick with the virus even though they “never” wore a mask or face covering.
Personally I feel like masks aren't stopping the spread mainly because people either use one or two masks continually without cleaning them daily, or put them on dirty surfaces thinking its ok and then putting them back on, or simply not wearing them over their nose. Masks would probably be effective if people wore them properly and only used them once. Hoping 300 million people all follow those simple rules is a bit hopeful to say the least.
There seems to be something different about the US population than, say, the Taiwanese population regarding mask usage. I don't have a good explanation for it, because I think blaming "culture" is lazy research.
And the WHO were too?
One has to balance that with awareness they’re talking out their ass.
All of these people thought they were smarter than the instruction I received from a real doctor, nurse practitioner, and the CDC. These were smart people, though, and mostly (but not limited to) highly educated engineers.