Why is the Government U-turning on masks?
It comes down to a question of evidence
We bought some tasteful face-masks the other day. I’d been wearing a crappy snood thing when I went into shops for a week or two, but it was a single layer of nylon and probably almost entirely ineffective.
The turnaround on mask policy has caught attention — the UK government began by telling people they didn’t work, then ‘advising people to consider‘ using them in enclosed spaces, now mandating them on public transport; other national governments and the WHO have been on similar journeys.
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To understand what happened there, it’s worth reading this post. It quotes an old BMJ paper, a joke one issued at Christmas, which pointed out that there are no randomised controlled trials showing that parachutes save lives when you jump out of a plane.
It’s pretty obvious why that is; you can’t ethically make 50 people jump out of a plane with a placebo parachute. So you have to make do with observational evidence — people who jump out of planes without parachutes tend to die more — even though that can’t, strictly, prove causality.
The same happened with masks. You can’t have a bunch of healthcare workers walking around hospitals with no masks on, because it would put patients at risk. So the studies never got done, so the evidence remained really bad. And medical regulatory bodies demand really high standards of evidence to say something works, so if something has bad evidence, they say it doesn’t work.
Normally that’s a good thing — it means they don’t end up licensing a bunch of crappy quack medicines — but in this case, it led to people confidently saying “masks don’t help” when they meant “we can’t prove masks help, but there’s a decent chance that they do”.
Now though more evidence is coming in. On Twitter, the statistical epidemiologist Adam Kucharski points to two studies, one finding that masks reduce daily growth rate of infections by about 40%, and the other finding no evidence that people start behaving more riskily if they wear them.
Both studies were carried out in Germany, because mask policies were introduced by different German states at different times, so that there was a natural control group (equivalent to the people being thrown out of aeroplanes with placebo parachutes): you could see if Covid cases dropped in states with mask policies and not in those without. It’s not a perfect method, because other things may be different, but it’s suggestive.
There are two lessons from this I think. One is obvious: people need to be better at talking about weak evidence and uncertainty, rather than “it works” or “it doesn’t work”. And the other is that if the evidence for some policy is weak, it’s a really good idea to allow local authorities some autonomy on whether to introduce it, in order to create these sorts of natural experiments which can provide better evidence.
I think it’s fair to say that now the evidence in favour of masks is pretty strong. And now I have my ones that actually work, that’s even better.
Ridiculous article with no evidence whatsoever that wearing masks prevents any way transmission. You need to watch Dr Vernon Coleman and take careful note of what he says. Masks are dehumanizing and dangerous
You’re allowed to click the links.
I believe that’s the plan. And the public is simply eating up!
Can you say more about this “plan”? Who made it? What is their goal? How does either wearing or not wearing a mask bring about their desired ends?
The author never set out to “prove” that masks prevent infections. He is sating some fact to encourage thinking and discussion.
I would refer you to an article on UnHerd a few days back that analysed SSEs. The single common characteristic they all shared were a lot of people in a confined space talking to each other, frequently with drink taken. Had they all been wearing masks (none were) they would not have been spraying and sprayed with large droplets at close range which both increased their chance of getting infected and increased their viral load.
Agreed, outside of drunken parties, funerals and business meetings, the utility of masks is questionable. Sitting quietly in a theatre, all facing front, and close to only the same two people for 2 hours is very unlikely to infect you, provided you don’t visit the bar in the interval. Ditto buses and aÃ©roplanes. The bus driver is not so safe however and would be well advised to wear a mask or sit behind a screen.
While I instantly agree in theory about everyone facing forward being a likely preventive, on further thought that only works if each head acts as an absolute collector / destroyer of the virus. But how likely is it that all aerosols and particles flow only straight onto the scalp you’re facing? Surely some are aerodynamic to flow around? And how can we know that virus that lands on the hair or scalp is rendered inert? Let’s say that person scratches the back of their head, then grips the shared armrest.
What happened to my lengthy reply?
I think it’s below this one.
So I now see! Where do they wander off to, and why do they return?
They get moderated first before being published.
I can only thank goddesses that attitudes like yours are worn plainly on your face, making it an easy thing to give you a wide berth. Who knows what other antisocial beliefs you hold?
Such evidence as there is suggest that (1) ordinary masks do little for the wearer’s protection BUT (2) probably reduce the range of travel of infectious droplets.
However, the incidence of infection in the community is very low. Mask wearing by the uninfected makes no difference. Ergo, mandating mask wearing now is as useful as shutting the door of a now empty stable.
There’s a difference between ‘very low’ and ‘zero’. They would obviously have been more effective much earlier, but the government and its scientific advisers are pretty useless, so that opportunity was missed. I still think compulsory wearing on public transport and in other enclosed public spaces is sensible, given the potential benefits against low costs/minor inconvenience.
Given that asymptomatic spreading, if it happens at all, is rare (& easily passes the same logic used in this piece), an even more effective way of reducing the rate of infections is simply not to travel around when symptomatic.
By the way, while I agree that properly worn masks probably do protect others, I have seen no evidence whatsoever that inhalation is a major route of infection. By which I mean, I’m doubtful that sufficient viral particles to cause infection can get delivered to a human body solely via their lungs. Be sure you appreciate that I do know that coughing / sneezing unwell people with virus are splattering virus onto all sorts of surfaces around them, but I’ve seen no evidence that touching those infected surfaces, followed by touching ones eyes, nose & mouth isn’t the main route of infection.
That would explain why there might be a minor effect of masks but mostly why hand washing is the only nailed on sound piece of virus transmission blocking advice.
I’d link to see a link to your claim, because everything I’ve seen has said that spread via contaminated surfaces is not a primary method of transmission. https://www.advisory.com/da…
It can happen, but the main route of transmission is via respiratory droplets when a person is close to an infected person, particularly for an extended period of time. Coughing or sneezing produces more of these droplets, but we exhale some amount of them with each breath.
I agree there is a difference between very low and zero. But it’s not much different. And not enough to make a strict policy that “thou must wearest thine mask”. I’m happy with “we recommend you wear a mask”. It’s a nice compromise. I personally don’t/won’t, except when I’m at work as a doctor, where I am mandated to. I agree masks are dehumanizing and get in the way of normal communication. If you read about the amount of subtle communication that goes on by facial expression, how evolved it is, how many muscles are in our face, and how much we lose when we cover our faces somehow, it’s clear to me that (except in rare circumstances) the disadvantages to mask wearing outweigh the advantages.
I am a strong believer in personal autonomy. If individuals do not feel safe leaving their house, or don’t feel safe being around other people without masks, they shouldn’t be out. The evidence there is RE mask wearing says that it doesn’t change the risk equation enough that these nervous types should suddenly feel safe just because folks are wearing masks. If you’re afraid or high-risk, stay home. Let the youngsters/healthy folks/brave folks go out, even if in your eyes they are not brave but foolish.
How you define “minor inconveniences” and “low-cost”? Their use implies that you need to replace them often. Each unit is a bargain, millions are a fortune! In relation to inconveniences many people probably would say that wearing a burqa would be as efective and more cost-effective than a facial mask. Do you would like to oblige all women to dress in burqa’s to travel on public transportation?
I think it should be decided locally if masks should be worn and under which circumstances. Here in Suffolk, esp West Suffolk, the (confirmed) infection rate is so low, I do not see any need. There is much “evidence” from supermarket workers, who have not worn a mask for 3 months, and shown no above average rate of infection.
I don’t understand the reasoning for this article.
Wearing masks can cause detriment both to the wearer and, hence, on a large scale, to the “herd”.
Facemask science references
World Health Organization
“the wide use of masks by healthy people “¦ is not supported by current evidence”¦ and carries uncertainties and critical risks”¦. There is no current evidence for their use.”
“”¦ there is currently no evidence that wearing a mask by the healthy can prevent infection with respiratory viruses including COVID-19.”
“Keep a distance of at least 1 meter from other people.”
British Medical Journal: 9 Apr 20
Covid-19: important potential side effects of wearing face mask
“Face masks make breathing more difficult. For people with COPD, face masks are in fact intolerable to wear as they worsen their breathlessness. Moreover, a fraction of carbon dioxide previously exhaled is inhaled at each respiratory cycle.”
“”¦mask fabric “¦ can determine an increase in viral load and therefore they can cause a defeat of the innate immunity and an increase in infections.” ” It is not time to act without evidence.”
British Medical Journal 2020 Face masks for the public during the covid-19 crisis
“no randomised trials of masks so far for COVID 19”
“we did not find any published data that directly support the use of masks “¦ by the public.”
“10 randomised controlled trials .. that tested the efficacy of face masks”¦ meta-analysis found no significant reduction in influenza transmission.”
“”¦31 eligible studies “¦ The evidence is not sufficiently strong to support the use of facemasks as a protective measure against covid-19.”
“Currently we are not finding any data that can quantify risk reduction from the use of masks”,
““ Reuters: April 23, 2020 / Partly false claim: Wear a face mask; COVID-19 risk reduced
Russell Blaylock PhD:
“By wearing a mask, the exhaled viruses will not be able to escape and will concentrate in the nasal passages, and travel into the brain.”
“When a person has TB we have them wear a mask, not the entire community of non-infected. The recommendations by the CDC and the WHO are not based on any studies of this virus and have never been used to contain any other virus pandemic or epidemic in history.
Face masks pose serious risks to the healthy ““ Blaylock
“Masks can spread all virus, but coronavirus specifically. Exhaled viruses will not be able to escape and may concentrate in the nasal passages. “
Perlman S et al. Spread of a neurotropic murine coronavirus into the CNS via the trigeminal and olfactory nerves. Virology 1989;170:556-560. https://pubmed.ncbi.nlm.nih…
From the peer review journal Influenza and Other Respiratory Viruses 6(4), 257″“267.
bin-Reza et al. (2012) “The use of masks and respirators to prevent transmission of
influenza: a systematic review of the scientific evidence”,
“There were 17 eligible studies. “¦ None of the studies established a conclusive
relationship between mask use and protection against inï¬‚uenza .”
Why Face Masks Don’t Work: ““ John Hardie, PhD
Many thanks for all this information. Most interesting to someone retired for a decade.
Blaylock is a crank and not to be believed. Some of your other references are over a month old and in citing them, you ignore the premise of this article, which is that as new knowledge is acquired, we’re finding that masks are effective.
So what if the references are a month old? We have had masks for decades or are we to believe that Covid has changed how masks work in the past month ! That’s insane although totally in line with government strategy, namely, to keep people compliant and doing EXACTLY what they are told. When decades of research are turned on it’s head exactly at the same time as government policy dictates public behaviour you have to be truly brainwashed to not think “What the hell….”
Okay, I’ll reiterate: There was a time at the beginning of this pandemic when masks didn’t seem too beneficial, but as it grinds on and is studied more, we’ve learned masks are a help. Has nothing to do decades of mask-wearing, or your paranoia about being controlled by the government. (In the decades before germ theory, surgeons routinely plunged their hands into one body after another without washing in between. Lots of people died of gruesome infection.) Things change, knowledge changes. Bright people pay attention to those advances.
Is this another correlation = causation study?
Wearing a mask cannot be better than social distancing. It might have some benefit where social distancing cannot be maintained. IMHO the main benefit is psychological. It means the person near me wearing a mask is thinking about my welfare as well as their own, which slightly increases my confidence that they would have stayed at home if they were experiencing symptoms.
Yes there’s another study. I put it in a comment in this comments section
You can not have an intelligent discussion about “masks” without distinguishing surgical masks from respirator masks. Surgical (any cloth mask) only prevents spit from falling into a surgical opening, that is incapable of immune response. When it comes to breathing, our nose is the filter. when contaminated micro droplets travel from your mouth to someone else’s breathing quadrant, their nose provides the immune response. The cloth mask only prevents some of the droplets, not the micro droplets (not the way the citizenry and even some nurses wear the masks!)
Your “scientific” approach is ridiculous. One of this days we will be forced to be on the beach fully clothed just because it lessens the ability of developing skin cancer! And yes, you can do a proper randomised control study on mask value in opposition to the parachute example (very silly comparison). If people don’t want to do it is because they think they know already the outcome: no value unless you sneeze, spit or cough directly to anyone, something that so far is not a cultural norm in the U.K. society.
All pre Covid research shows that masks are effective at protecting others from what you (the mask wearer) has. Hence why masks are worn by surgeons and have done so for decades. The packets the masks come in state quite clearly they do not protect the wearer. Now all of a sudden at exactly the same time as government “directs” the compliant population to wear masks along comes research that shows the wearer is protected……..really!
The following is a link to an excerpt from a question and answer session, held by the WHO on Monday 8 June 2020, in which Dr Maria Van Kerkhove, head of WHO’s emerging diseases and zoonosis unit, answers a question, saying that, from evidence gathered, asymptomatic people rarely infect someone else. If that is true, how can wearing masks make any difference? Could it just be that, where masks are being worn, numbers of infections are naturally reducing anyway? https://www.youtube.com/wat…
That WHO finding has been walked back. Up to 40% of cases are now believed to be contracted from a- or pre-symptomatic carriers.
The science on this virus is very fast-moving, and very little is known for sure. The best we can do is keep up with the data as it emerges until we converge on consistent findings. For example, we went from “COVID doesn’t affect children” to “COVID appears to affect some children with serious symptoms that aren’t seen in adults.” We’re also seeing cases that don’t resolve; only time after the onset of illness could have given us info on a subset of cases that persist for 60, 90, or more days.
Emerging science tells us that, up to 10% of our human genome has viral elements – of which coronavirises compromise the largest proportion – such that the amplification tool (not meant to be used as a clinical test) called the RT PCR could use varying numbers of repetitions to demonstrate that viral DNA is present in anyone. It’s not a case for broad-sweeping policies for misuse of an amplification tool as a clinical test for listing covi “victims” or initiating quarantine of healthy people.
Correlation does not equal causation.
Thanks Tom, The obvious confounding factor in the parachute analogy; is the plane in the air or on the ground?
My experience with airborne mould spores and asbestos is that they are most dangerous for mouth breathers and antihistamine users or smokers. Inhaling directly into lung tissue is the problem.
So with airborne covid19 virus there is a large risk of getting the virus in your lungs via your hair and pillow as you sleep and snore!
Washing your hands till they bleed is no protection but does advance the medical dogma of germ theories.
As for masks, if they cause you to breathe through your mouth or go into contaminated air they are more of a problem than a solution.
If masks worked against viral diseases like the common cold and flu the Japanese would get much lower rates of cold and flu infections.
If this was true the mask lobby would shouting this from the roof tops but they aren’t are they
I remember when Muslim women were oppressed by being forced to wear masks.
It’s pretty obvious why that is; you can’t ethically make 50 people jump out of a plane with a placebo parachute. So you have to make do with observational evidence ” people who jump out of planes without parachutes tend to die more ” even though that can’t, strictly, prove causality.
But of course you don’t have to make do with observational evidence, and the BMJ parachute paper nicely satirises the idiotic EBM approach to inference that leads both to unwarranted belief in the efficacy of homeopathy and to unwarranted disbelief in the efficacy of masks (or parachutes).
It seems to have worked out better than usual. The Govt has been announcing things at short notice, creating issues when sufficient is not available – including opening the door for scam artists. Hopefully the way this has played out has avoided many of those problems. As I rarely use public transport I am in no rush to get a mask and will take my time to get one that is both effective and comfortable.
I favour the precautionary principle. Masks may not be as effective as some people claim, but do they do any harm?
PS. Your broadcast on uncertainty ( BBC4 Radio) illustrated the point.
Yes if you oblige others to use it. Imagine if a study comes out saying that Burqa’s protect against Corvid19 and from now on every woman in Britain must dress in Burqa. What would be your comment?
Yes. Mask wearing during a virus outbreak can do harm to an individual, causing rebreathing of virus particles which can then concentrate and travel along the trigeminal nerve (5th cranial nerve) and along the olfactory nerve (1st cranial nerve) spreading the above to the brain tissue.
Further to this, 1 out of 10 people “carry” niseria meningitis in their nasal passages – all of the time – and 1 out of 3 individuals carry staphylococcus aureus in their nasal passages – all of the time, again, mind you. So… if you’ve been alive any length of time and been in a venue indoors, you’ve rebreathed the human virome (natural viruses and/or inclusive of the above-mentioned bacteria) without having ever been in any way compromised — in fact — by being exposed to the natural human virome we build natural immunity protection for events such as this.
The only exception being severely immune suppressed individuals, for example those who are undergoing the toxic side effects of chemo. where an extra cautious approach may be a help so long as it’s not overdone to the point that they’re completely suppressed.
There is more evidence to suggest detriment by mask wearing of healthy individuals than any risk of detriment from natural exposure, quite the contrary. As mentioned above detrimental effects can arise from the healthy wearing a mask for any duration.
There are millions of viruses and exosomes in our daily environment – our human virome, viruses in the sea, in the soil, in every aspect you’ve been “exposed” to which has helped you develop immunity.
You’re being obtuse. HCWs are masked during the hours they’re at work. Several hundred have died of COVID, yet no one has died of the other rare conditions that mask contrarians like to trot out. (The same people claim there are more deaths from suicide, overdoses, and domestic violence than are lives saved by sheltering in place. They don’t provide any solid stats to back up those assertions, either.)
Can someone demonstrate the solid evidence that these people actually died of covid19?
What clinical testing was used for the definitive diagnosis?
What treatment pathway was used?
Can you please reply without extrapolation and without name-calling?
Obviously you are frustrated.
Masks are a positive approach. Even if it gives a low level of protection for the wearer it is beneficial for others close by. Consider the wearing as being a good member of the community.
Positive in what? They thought that masks would be protective for everyone in the operating theatres. Then they studied and found that it was irrelevant for others than surgeons on very high risk surgeries (brain and orthopaedic procedures). That’s the difference between science and belief.
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