Prevent person-to-person transmission of SARS-CoV-2 | Hacker News Reader

Prevent person-to-person transmission of SARS-CoV-2

thelancet.com

58 pointsdoener74 comments

Seeing these studies and NYTimes talk about the widespread use of masks in 1918 makes me angry that in 2020 public health officials thought it was a good idea to lie to the public for months with vague dismissals of the benefits of masks - merely to protect supply chains for doctors (both Dr Fauci and officials here in Canada have admitted they purposefully kept it vague for the benefit of health care workers).

It set back a really important protocol in western countries that asian countries had already adopted and clearly had success with. By the time they switched on the masks-everywhere messaging we were well into the mass spread of COVID.

This sort of "protecting people" through deception or indirection is the sort of thing I despise from governments.

The side-effects of not immediately stating their usefulness to the public - while no doctor would go near a COVID-19 patient without a full face + eye mask - is still being felt today.

Absolutely. This was a disinformation tactic adopted from the modern Republican playbook. Don't lie to people and then blame Republicans for lying to people. Reality matters. Intellectual hygiene matters.

It is very easy to politicize this, but it wasn't just the party in power: Supposedly independent healthcare organizations in the US gave outright and easily disprovable safety information for at least two months.

We had studies about similar airborne illnesses that showed mask's effectiveness, and while I am sympathetic to protecting key medical supply lines, they have done long term harm to public trust and mask adoption.

The anti-maskers we're seeing today are directly their fault.

Even now, we're still seeing misinformation about the difference between cloth and N95 effectiveness, particularly as the US has failed to ramp up N95 production after months of seeming inaction. Even healthcare providers are still struggling with PPE, let alone the general public or educators with the upcoming school re-openings.

While I agree with your point, there were also anti-maskers during the Spanish Flu, so these anti maskers aren't entirely the fault of the deception.

https://en.wikipedia.org/wiki/Anti-Mask_League_of_San_Franci...

I agree that we'd always have some anti-maskers. But the level of it (seemingly mainstream) has been quite problematic (although the tide does seem to be slowly turning).

> It is very easy to politicize this, but it wasn't just the party in power

That's what I'm saying. Non-Trump people took a move out of Trump's playbook. That's vicious.

> The anti-maskers we're seeing today are directly their fault.

I wouldn't go that far. Anybody who is still anti-mask at this point is just an anti-reality nihilist.

Despite my other comment (sibling to this one), I do regret mentioning Republicans and Trump. It wasn't necessary to make my point and was in poor taste and poor form.

Speaking as someone who absolutely loathes Trump, a number of serious mistakes have been made by people including Dr. Fauci and Governor Cuomo that they are largely getting a pass on because they are being graded on a curve so to speak against Trump's complete failure.

This is not exactly what happened. U.S. medical authorities really did not believe that basic masks, like fabric or paper surgical, offered significant protection. Thus they believed it was N95 or nothing, and they (correctly) wanted to save N95s for medical professionals.

They were wrong about basic masks, which is what we're all using now.

The virus had not been well characterized at all, yet they were very certain of the opinions they expressed to the public. I can't forgive this.

It wasn't like they just guessed or anything. IIRC they had a test where people coughed into a petri dish with and without masks. The initial results showed that there was coronavirus on the outside of the mask, leading them to conclude that the virus is able to get through the mask. They weren't able to realize they were incorrect on their conclusion until they looked at the cultures a few weeks later and measure the amount of coronavirus in them.

I could be wrong on that, if someone is better-informed please correct me, but that's what I read somewhere.

EDIT: Just to clarify before I'm downvoted, I do actually agree they were a bit too hasty to tell people not to buy masks. Having the surgeon general tweet out saying "Seriously people, DO NOT BUY MASKS" was definitely premature and obviously led to a lot of the problems we're having here now. I just wanted to point out that it wasn't a completely unfounded take, just premature to make huge decisions like that.

I don't think this is fair; in real time you have to either go with what you think you know, or do nothing at all. If they'd done nothing at all, I think they would still be getting at least as much criticism now.

Why not advise to err on the side of caution until a meaningful quantity of knowledge is available?

This feels like a re-writing of history. There was no nuance in what the US Surgeon General said, no mention of N95 vs. "basic" just "[masks] are NOT effective." Here's the full quote and tweet that still exists:

> Seriously people- STOP BUYING MASKS!

> They are NOT effective in preventing general public from catching #Coronavirus, but if healthcare providers can’t get them to care for sick patients, it puts them and our communities at risk!

I get wanting the best interpretation, but there's a difference between that and just outright mischaracterizing what the message was from public health officials around Feb.

https://twitter.com/surgeon_general/status/12337257852839321...

I don't think this tweet conflicts with what I wrote.

Sorry I saw an interview where Fauci said that they knew earlier that masks would help but advised not to use them because hospitals needed the PPE. I can't find the interview, I did a search to find articles on it though.

https://www.businessinsider.com/fauci-mask-advice-was-becaus...

He may not have known that regular cloth coverings would help but by discouraging the use of any masks he undercut his argument later.

Maybe - He was saying, they knew 95 masks would help but didn't know other masks would. Either way, it feels very dishonest.

Ok, you have perfect hindsight knowledge of the situation. Understanding that N95 masks were in short supply, knowing the virus wasn't particularly widespread, but more widespread than people realized and health care providers are on the front lines and dealing with it already. And the science on masks isn't fully understood either in terms of spread or protection.

What would you have done, what would you have said? What would have not been dishonest?

Also, what are you going to say so you aren't accused of: fear-mongering, overreacting, or being wishy-washy and providing useless guidance?

Taiwan CDC had perfect foresight knowledge of the situation, then. Of course, most US government agencies have massive Not Invented Here syndrome, but the answer was obvious. And funnily enough, Tech Twitter (the subculture) was full abuzz with this in March.

The idea that, in a situation encountering a SARS, that you wouldn't call the guys who beat a SARS is so fundamentally silly. Especially when they're ridiculously friendly to you. That's part of what I love about startups - every successful entrepreneur tries his best at learning from everyone else's successes and failures. It's not enough to learn by yourself, you won't get there in time.

So, no, I'm not surprised they couldn't do it because they have institutional cultural failure. I don't think I could do it at the CDC either because of the cultural failure (NIH, Perfectionism, etc.). It's hard to say, we'd have to see the nuances of power in CDC vs NIAID, whether it would be politically viable even for Anthony Fauci to call Chou Jih-Haw, let alone Tsai Ing-Wen etc., and governments aren't like companies where the CEO can just set up a team of people to bypass the normal structures and collaborate with Taiwan. The CDC and gang may be broken beyond repair. I think that's the best defence you can give them.

The truth...

I don't know if this is the interview that you are referencing but here is one place where he says it: https://youtu.be/GbfiqxDgOZ0?t=165

paucity - Scarcity; dearth.

I time stamped it to where he makes the statement after the political posturing.

This is an oversimplification considering that there were also drives to donate surgical masks and even homemade cloth masks to hospitals for use by professionals.

My sibling is a nurse; they put surgical masks over their N95s to protect them and try to help them last longer.

>> offered significant protection

Which, by the way, they do not if it's only the healthy who are wearing them or if people are wearing them with their nose sticking out above. And even if they did, C19 is now endemic, and without a vaccine (which might not ever materialize), everyone will get it eventually, if not now then 6 months from now. So lose that weight, deal with that blood pressure problem, manage your diabetes, while you still have the time.

As an aside, I find the response to C19 to be tragically (or comically, depending on your perspective) bad on the ground in almost all countries. Get this - one of the most reliable, easy to instantaneously test markers for whether you are _definitely_ infectious or not is _fever_. Contactless, accurate IR thermometers exist and could be deployed in arbitrary quantities. FLIR cameras also exist, and object detection algorithms can be run on-device in 2020 to identify the potentially sick people. And yet we do not measure people's body temperature when they enter public places such as a grocery store. It is well understood that we need to protect the elderly, yet instead of making it possible for the elderly to stay home indefinitely (by e.g. offering government sponsored groceries, or at least grocery delivery) we make them go to the grocery store. Several states went as far to thin the herd as to put C19 patients _into nursing homes_, which is absolutely insane. Medical personnel in some of those nursing homes is still not sufficiently isolated from the general population. Close to a half of US deaths are from those nursing homes - the statistic has been known for a couple of months now, but you won't find it in the press, for obvious reasons.

Why is this? Remember cringing when you had to vote for local candidates? People with little to no qualifications, some of whom (at least where I live) tell you in their candidate disclosure they're mentally ill? Those same people, after they are elected, go up the ladder, and some of them end up in the higher level positions in local and state governments. It's similar to Gell-Mann amnesia, in a way. They're still inept and insane. They're only there because other candidates were even worse. Yet people imbue them with some magical leadership and intellectual qualities they do not possess and rely on them with their lives.

There should really be "against all" option on the ballot.

IR body temperature scanners are actually not accurate, especially when used in public setting like a grocery store. Many infected people don't run a fever.

But they are _likely_ to run a fever if they are symptomatic. And between 100% "non-accuracy" of not measuring temperature at all, and some much higher level of accuracy of a non-contact IR thermometer, I pick the latter. I have one BTW, it seems pretty accurate to me (confirmed with a calibrated thermopair, unless you're trying to measure something reflective or transparent).

Cheap general purpose IR thermomenters from Melexis claim greater than +-0.1C accuracy in the common "body temperature" range: https://www.mouser.com/new/melexis/melexis-MLX90615-infrared...

There will be lasting consequences of that lie for the rest of the pandemic probably for decades to come. There is a sizeable anti mask movement that gained significant ground because authorities told people masks didn't work despite the science saying the opposite, they even fabricated it as a scientific position further hurting belief in science itself.

Many governments of the world created an anti vaxxer like movement around masks just to protect supplies. They had to do so because they failed to act early enough and to follow their own recommendations for stockpiles of protective equipment. The consequences of those lies will be here for a long time.

This is particularly damning given that we're also now being told that a bandanna or any piece of cloth is a suitable replacement for a mask. Assuming that's true, it's pretty hard to justify lying to people about mask efficacy for the first several months of the pandemic. Would people have listened if they were told: masks work, but are in limited supply so use a bandanna and save the mask supply for front-line doctors? Probably not completely, I'm sure many people would still have gone out and bought masks impacting the total supply. Would it have been worth it, looking ahead, to not lie to people and degrade their trust in medical professionals, so that in the future when you decide to reveal the truth to people that masks actually do work they'll believe you? I think it probably was, but who knows.

> we're also now being told that a bandanna or any piece of cloth is a suitable replacement for a mask.

We are not. But we are being told it's better than no face covering, which is true.

You are, personally, wearing a mask though, right?

It isn’t established that mandatory face masks is a worthwhile policy decision. I refer to the Swedish health authority for analysis of the current findings.

Ah downvoted without rebuttal, how cowardly.

I didn't downvote. I'll offer this.

This (the quote is from the Swedish health authority) was proven wrong yesterday. People touch their face less with a masks. Based on cctv studies in England.

"a face mask which is itchy and falls below the nose contributes to your hands often touching the mouth, eyes and nose which can increase the risk of infection"

The question is not simply “do masks have any benefit”, it’s “do masks have enough benefit to be worthwhile mandatory policy”.

There are many ways to deal with this pandemic, and it’s getting more and more “with us or against us”. This censoring that Twitter et al now engage in is very, very troubling.

South Korea did an amazing job, as outlined in this NYT article [1]. The thing I liked the most is my Korean map app had a new tab, showing me all the official mask distribution locations, and their real time quantities on hand.

[1] https://www.nytimes.com/2020/04/01/opinion/covid-face-mask-s...

> public health officials thought it was a good idea to lie to the public for months with vague dismissals of the benefits of masks - merely to protect supply chains for doctors

It was weeks, not months. By mid-march, conventional wisdom had shifted, as had most of the official rhetoric. This was before or simultaneous with most of the early lockdowns.

And it was wrong. But the real harm was caused much later when political actors started arguing not based on this early advice that masks were ineffective/harmful/tyrannical, or (even worse) that the expert advice now was not to be trusted because the experts then got it wrong.

Basically: the people who refuse to wear a mask aren't the ones slavishly honoring the whims of the WHO or Fauci, so I don't understand your point.

I will say - I do understand why they did it, because nobody told anyone toilet paper was useful or important with the virus and look at how that went out of control. Just think if they suggested masks or even “face coverings” - people would definitely have saturated the market.

However it did suck as that helped cement some anti-masker excuses early on.

Hard to tell if there is any winning in that situation. :(

This study talks about 12-16 layer cotton masks as being the most effective. They say this offhand, as if that's a thing. However, it's very difficult to find anything with more than 3 layers. None of the citations to that claim give any hints about how to find 12-16 layer cotton masks (in fact, one of the citations to that claim is a paper that couldn't determine the efficacy of one mask-type over another).

I think you interpreted this wrong. N95 were associated with higher reduction in transmission than others (eg. the 12-16 layer cotton masks you mention).

Yes, that's true, but the 12-16 layer masks were ostensibly superior to single layer masks. The authors seem to treat "12-16 layer" masks as somewhat equivalent to surgical masks throughout the article, which might answer my original question.

"For the general public, evidence shows that physical distancing of more than 1 m is highly effective and that face masks are associated with protection, even in non-health-care settings, with either disposable surgical masks or reusable 12–16-layer cotton ones, although much of this evidence was on mask use within households and among contacts of cases."

In another part, they compare 12-16 layer/surgical masks to single-layered masks, ranking the single-layered as less effective.

Regarding aerosols, the authors write that it is not possible to draw conclusions yet, because they could not find enough supportive data on aerosol transmission. Please note that they only consider sources before May 3, 2020.

Looks like what we've been hearing is backed up by this study:

"Interpretation The findings of this systematic review and meta-analysis support physical distancing of 1 m or more and provide quantitative estimates for models and contact tracing to inform policy. Optimum use of face masks, respirators, and eye protection in public and health-care settings should be informed by these findings and contextual factors. Robust randomised trials are needed to better inform the evidence for these interventions, but this systematic appraisal of currently best available evidence might inform interim guidance."

I've not seen any recommendations for public use of eye protection, is that being done anywhere? Are some places recommending wearing some type of goggles or something?

IIRC, some news reports stated Fauci mentioned something about eye-protection last week. Haven't heard anything more concrete than that. It makes sense, but... I doubt most people will do it. I wear glasses half the time, which... I dunno - may be slightly useful?

FWIW, as far as I am concerned, I would wear goggles if made mandatory or highly recommended (as long as the kind of recommended googles are sufficiently well described).

On that note I don't see anyone left wearing surgical or latex gloves outside now (Western Europe).

Because the gloves are mostly pointless, if not making the problem worse. It's better to not touch your face and sanitize your hands. All the cashiers here don't use gloves. They sanitize their hands after every transaction, they wear face masks, plexiglass shield around their station, and there is a limited number of people allowed in the store, with a 1m physical distance between customers enforced. This is the requirement in South-Western Ontario. So far it's working fantastic over here. All decisions have been informed by scientists and experts in their fields.

"They sanitize their hands after every transaction"

They use soap and water? Handwipes?

That must be killing any skin they have left. Gloves make so much sense for them. They make sense for everyone.

They use hand sanitizer. It contains moisturizer as well.

Gloves are scientifically proven not to work unless you replace them after every transaction, additionally most people do not know how to properly remove surgical gloves without contamination.

That makes sense overall. But they work for the worker who wears them (just not the public). Longer term healthy workers won't be sick and spread as much.

Taking off gloves shouldn't be an issue. I would think after a 4 hour shift you would take them off and wash hands because they would be sweaty anyhow and you would smell of rubber.

I've worn them when browsing in a store, but the point of the gloves in that case is to prevent my transmitting it to someone else via a point of contact and not to protect myself from receiving the virus.

Transparent face shields might actually be nicer to wear than masks, if that's all you needed, because you can still see each other. I saw someone on the street using one once.

Unfortunately, they haven't been studied much, and I've seen a couple reports that face shields alone are not enough and they are best combined with masks.

Still, a face shield alone would probably be better than nothing.

> Transparent face shields might actually be nicer to wear than masks, if that's all you needed, because you can still see each other.

Alone, face shields do little to nothing to protect people from the wearer.

Most footage during the Wuhan lockdown had a near majority wearing goggles in places like grocery stores.

Yeah, they were wearing swim goggles, like this Irish badass in Wuhan at the end of January:

https://www.youtube.com/watch?v=luztqxUBvZo

Do glasses help, or do you need goggles?

Glasses obviously help and is better than nothing, it is a screen in front of your eyes.

That’s because this isn’t a “study”, it’s a review.

A review introduces no new information - it summarizes the existing literature.

This is the meta-review commissioned by the WHO to investigate the value of PPE, and it is notable because it aggregates a number of low-quality studies and attempts to statistically re-weight their data to arrive at a broader conclusion.

It’s notable for face masks, in particular, because it mixes data from hospital settings with community settings, along with respirators and surgical masks, source control and PPE, and attempts to draw a conclusion about “protectiveness” overall.

My dentist wore a full-face clear plastic shield yesterday, which obviously provides eye protection and let him work while staying protected. I wouldn't be surprised if this becomes standard practice ever more.

That’s not true if the particles are aerosolized (why dentistry is so high risk) and simply go around the face shield into the eye. Eye googles would be far more effective.

I dug through to find a few of the underlying studies on the topic of masks, which is a controversial topic. I looked at three of the studies they cited that had high N numbers for enrolled patients:

[1] https://www.medrxiv.org/content/10.1101/2020.04.20.20064899v...

[2] https://pubmed.ncbi.nlm.nih.gov/12737864/

[3] https://www.medrxiv.org/content/10.1101/2020.04.20.20064899v...

These studies all are focused on the protective aspect of masks: does a mask prevent you from getting various coronaviruses? Also, they are all focused on health care workers who interact with sick patients. The studies find that wearing masks and taking other protective steps reduces the danger to health care workers.

There is big a leap though, from the conclusions of these studies to global mask mandates. Some reasons:

(1) If masks protect the individual, then individuals can make their own decisions about mask use. If you are more concerned about getting covid, you wear a mask to protect yourself.

(2) Health care workers interact with a lot more sick patients than the typical person. If interact zero or just a handful of sick patients a day, your risk calculation is a lot different than if you interact with a dozen sick people each day.

(3) I haven't seen any studies that look at the benefit of wearing a mask all the time as oppose to wearing a mask when you have symptoms. This would be very interesting and relevant, since it's likely that the most contagious period is when you are sick (coughing, sneezing, sinus congestion)

In all, digging into the data doesn't really support global, 100% mask mandates. It does support masks to protect yourself, and mask wearing in certain situations (hospitals, for example).

I see on page 3 of the paper it says 118 studies were excluded for "Wrong Outcomes" but I couldn't find any elaboration on what was meant by this. Were papers tossed out based on arbitrary criteria? This would suggest a bias, no?

Outcomes in research papers refer to the specific values that were being measured. In this case, "wrong outcomes" means that the studies that were discarded were not measuring FOR the values that they're comparing across.

"Outcomes of interest were risk of transmission (ie, WHOdefined confirmed or probable COVID-19, SARS, or MERS) to people in health-care or non-health-care settings by those infected; hospitalisation; intensive care unit admission; death; time to recovery; adverse effects of interventions; and contextual factors such as acceptability, feasibility, effect on equity, and resource considerations related to the interventions of interest. However, data were only available to analyse intervention effects for transmission and contextual factors. Consistent with WHO, studies generally defined confirmed cases with laboratory confirmation (with or without symptoms) and probable cases with clinical evidence of the respective infection (ie, suspected to be infected) but for whom confirmatory testing either had not yet been done for any reason or was inconclusive."

From the study abstract:

"Our search identified 172 observational studies across 16 countries and six continents, with no randomised controlled trials"

Don't have a chance to read the full article until later. Does anyone know if they are controlling for confounding factors (e.g. urban/rural, public/private settings)?

They are not. They freely mix studies from different circumstances.

For example, the “mask” section mixes data for respirators and surgical masks, and does not differentiate between hospital or community use, source control or PPE, when they make their top-line conclusions.

If you look at the breakouts, you’ll note that most of the data showing effectiveness for masks is for respirator use in hospitals.

Surely that's mentioned in the limitations of the study? In my quick scan of the abstract, I don't recall seeing anything about it. Could have missed it though.

It is not in the abstract.

Something I see not often mentioned (as a long-sufferer of both of them) is that since COVID is much more highly contagious than either the standard set of flu virii OR the standard set of rhinovirii (common cold) (what I've read, IIRC, is that COVID is 3x more contagious than those: the median R0 for COVID is 5.7 https://www.healthline.com/health/r-nought-reproduction-numb... and the flu has an R0 of 1.3 https://www.nytimes.com/interactive/2020/world/asia/china-co... and the cold, 1.5 https://www.medrxiv.org/content/10.1101/2020.02.04.20020404v..., see table 1), all the work we're doing to stop COVID transmission may be having an even greater effect on flu and cold transmission.

I talked to a biologist friend about the possibility of those being eradicated as an unintended positive side effect of our anti-COVID efforts, and he suggested that the animal kingdom unfortunately can serve as a zoological reservoir of some of these viruses and could potentially retransmit them back to humans, so it probably wouldn't entirely eradicate them, but it might certainly drastically hamper them for years.

I for one will be happy to take "will not experience a cold or flu for the next... who knows how many years" as a 2020 consolation prize.

Things I did not know while researching this comment:

The common cold costs the US economy $40 billion a year, and Amazon is secretly working on a cure: https://www.cnbc.com/2020/03/06/amazon-is-secretly-working-o...

The 2018 flu season cost businesses an estimated $15.4 billion https://money.cnn.com/2018/02/02/news/flu-season-business-co... and sufferers $10.4 billion in hospitalizations and outpatient expenses https://www.cdc.gov/flu/pdf/business/Toolkit_Seasonal_Flu_fo...

That seems to imply that the combined economic benefit of nearly eradicating both could result in an economic boon of $65 BILLION a year, and that's just in the United States! Not to mention all the people who won't die of the flu, etc...

but 1 flu or cold sufferer only infects an average of 1 other person)

If that was the case then flu or colds wouldn’t spread the way they do.

There is not just one cold virus, there are many. So the 1-1 average sounds reasonable.

yeah, I've corrected the data and the claim in the original comment

> the animal kingdom unfortunately can serve as a "repository" (I forgot the word he used)

The term "reservoir" is used in this context.

Thank you. Comment is now edited.

I think R0 for the flu is usually take to be in the range 1.4-1.6 and for the common cold, 2-3. It's significant that it is quite a bit over 1, as it wouldn't spread so effectively if not.

It's an exponential factor, so small differences in the value make a big difference.

On the other hand, R0 for SARS-Cov-2 has been estimated as high as 6 by some groups.

[1] https://en.wikipedia.org/wiki/Basic_reproduction_number

I've added more accurate R0 values, with links to source for each, for COVID19, the flu, and the cold, to my original comment:

median R0 for COVID: 5.7

Flu: 1.3

Cold: 1.5

Of course, R0 is a context-sensitive value, so all this is debatable. But I think claiming COVID is 3x as contagious as the other 2 is not that far off the mark.

This could apply to COVID-19 as well:

'As SARS-CoV-2 has a novel receptor binding interface (compared to SARS) & circles the globe, opportunities for new animal reservoirs become available. We could suddenly see some common animal in the US being a reservoir for this virus for the future'

- http://microbe.tv/twiv/twiv-591/

i have no idea how trustworthy this source is but it looks like the flu/cold isn't handling covid19 protections and procedures very well.

"South Africa also has reported startling declines, with doctors saying there haven't been a sufficient number of flu cases to even report that the seasonal epidemic happened. And in Australia, the country's National Notifiable Diseases Surveillance System recorded only 85 new laboratory-confirmed cases of influenza in the last two weeks of June—a stark difference from the 22,047 confirmed cases recorded during the same time last year."

https://www.advisory.com/daily-briefing/2020/07/24/coronavir...

I guess, unless it's zero though, exponential growth will cause it to eventually reach its last-year equilibrium again... :(

I hope that even if this situation doesn't eradicate other diseases, it at least pushes us to take more care with infectious disease in general.

Since I've been exposed over the last few months to roughly a million people claiming that COVID19 is no worse than the flu, it prompted me to look up just how many people die or are hospitalized from the flu every year.

US avg annual deaths (prev 9 years): 37,000

US avg annual hospitalizations (prev 9 years): 446,000

Clearly COVID19 is worse than this already (160k deaths, 317k hospitalizations, and more every day).

But put aside the COVID19 comparison, and that is still a lot of people who suffer or die from something that we have tools to prevent. How much of that could be avoided with better flu vaccine uptake, policies that support staying at home when you're sick, and the normalization of wearing masks in public?

Why weren't we already doing all of those things? I only did one of those things, and that feels kind of dumb now.

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