Surgical masks reduce Covid-19 spread, large-scale Stanford study shows • Hacker News Board

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#21

Post by majormajor » Fri, Sep 03, 2021, 6:02 PM UTC

slg wrote: post #16

majormajor wrote: post #11

Earlier quoted context omitted.

It's surprising to me that cloth masks can't even do the 11% of surgical masks. Which isn't much, but surgical masks are non-optimal for many reasons. Not to mention that this doesn't seem the same as "while wearing a surgical mask you only get 11% increase in protection" but is a population-level thing. There was still non-compliance that presumably lowered the efficacy. I would've intuitively guessed that the bette…

>It's surprising to me that cloth masks can't even do the 11% of surgical masks. Just want to add clarification here. The 11% number is the community impact of the programs designed to increase mask usage. It is not the effectiveness of a mask on an individual level. That number will be much higher since as you said a number of people didn't/don't comply at a societal level.

Thanks! I edited my comment to add notes on that too. At a population level even a small portion of the population wearing masks reducing overall spread is very good to see. Even for surgical masks.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#22

Post by nielsbot » Fri, Sep 03, 2021, 6:02 PM UTC

majormajor wrote: post #11

ch4s3 wrote: post #3

> There were significantly fewer COVID-19 cases in villages with surgical masks compared with the control villages. (Although there were also fewer COVID-19 cases in villages with cloth masks as compared to control villages, the difference was not statistically significant.) This aligns with lab tests showing that surgical masks have better filtration than cloth masks. However, cloth masks did reduce the overall like…

It's surprising to me that cloth masks can't even do the 11% of surgical masks. Which isn't much, but surgical masks are non-optimal for many reasons. Not to mention that this doesn't seem the same as "while wearing a surgical mask you only get 11% increase in protection" but is a population-level thing. There was still non-compliance that presumably lowered the efficacy. I would've intuitively guessed that the bette…

The idiocy is intentional and is manufactured by rightist media (and others) hoping to win the bloc of anti-mask "freedom" stance voters.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#23

Post by cfn » Fri, Sep 03, 2021, 6:03 PM UTC

dragontamer wrote: post #2

> The researchers enrolled nearly 350,000 people from 600 villages in rural Bangladesh Wow. I was about to complain about "small n", but... an experiment of this size is not small at all. Congrats on the researchers on doing such a big study!

I think it is a bit cheeky of them. They promoted the usage of masks and distancing in 600 villages totalling 350,000 people and observed the results (mask wearing plus distancing) in mosques (by sampling, not by checking each individual).

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#24

Post by nielsbot » Fri, Sep 03, 2021, 6:03 PM UTC

dragontamer wrote: post #18

majormajor wrote: post #11

Earlier quoted context omitted.

It's surprising to me that cloth masks can't even do the 11% of surgical masks. Which isn't much, but surgical masks are non-optimal for many reasons. Not to mention that this doesn't seem the same as "while wearing a surgical mask you only get 11% increase in protection" but is a population-level thing. There was still non-compliance that presumably lowered the efficacy. I would've intuitively guessed that the bette…

I think most of us got cloth masks with the full expectation that they were worse than proper PPE from hospitals (be it surgical masks or N95 masks). I'm not sure if people remember: but there was a shortage of masks of all kinds in March 2020. Cloth masks were the only thing we could get, and we all knew they were kind of crap (a lot of us were using coffee filters stapled onto the masks to increase its effectivenes…

Seems quite reasonable to wear a (K)N95 instead of a surgical mask. Slightly less comfortable, but yes, affordable for most.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#25

Post by weaksauce » Fri, Sep 03, 2021, 6:03 PM UTC

chitowneats wrote: post #4

From Martin Kulldorff, esteemed (though contrarian) Harvard Med epidemiologist: "Odd that mask advocates are excited by this study. As a vaccine advocate, I would be horrified if a vaccine trial showed 11% efficacy. Based on the 95% confidence intervals, we do not even know if surgical mask efficacy is more than 0%." https://twitter.com/MartinKulldorff/status/14332026511062016...

because compliance was voluntary... the study merely had leaders in the community wear masks and provided free masks to those that wanted them plus education and reminders; it wasn't a compulsory thing so this is mainly a lower bound on effectiveness.

> Providing free masks, informing people about the importance of covering both the mouth and nose, reminding people in-person when they were unmasked in public, and role-modeling by community leaders tripled regular mask usage compared with control villages that received no interventions, the researchers found.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#26

Post by barbazoo » Fri, Sep 03, 2021, 6:04 PM UTC

exabrial wrote: post #6

This is truly great news, as we've need some controlled studies. However, _mandates_, literally threatening people with police violence, bodily or financial harm, is not the correct way forward. I think the best solution is improved mandates for airflow. It's a lot easier to improve airflow in a building than it is to police and enforce a mask mandate.

I don't get this mindset at all. Temporarily masking up at pretty much zero impact to the user vs. upgrading all building's HVAC system.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#27

Post by kragen » Fri, Sep 03, 2021, 6:04 PM UTC

input_sh wrote: post #9

chitowneats wrote: post #4

From Martin Kulldorff, esteemed (though contrarian) Harvard Med epidemiologist: "Odd that mask advocates are excited by this study. As a vaccine advocate, I would be horrified if a vaccine trial showed 11% efficacy. Based on the 95% confidence intervals, we do not even know if surgical mask efficacy is more than 0%." https://twitter.com/MartinKulldorff/status/14332026511062016...

And then see this response to that claim by one of the study's authors: https://mobile.twitter.com/Jabaluck/status/14331294449405992...

Better link: https://birdsite.xanny.family/Jabaluck/status/14331294449405...

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#28

Post by majormajor » Fri, Sep 03, 2021, 6:05 PM UTC

dragontamer wrote: post #18

majormajor wrote: post #11

Earlier quoted context omitted.

It's surprising to me that cloth masks can't even do the 11% of surgical masks. Which isn't much, but surgical masks are non-optimal for many reasons. Not to mention that this doesn't seem the same as "while wearing a surgical mask you only get 11% increase in protection" but is a population-level thing. There was still non-compliance that presumably lowered the efficacy. I would've intuitively guessed that the bette…

I think most of us got cloth masks with the full expectation that they were worse than proper PPE from hospitals (be it surgical masks or N95 masks). I'm not sure if people remember: but there was a shortage of masks of all kinds in March 2020. Cloth masks were the only thing we could get, and we all knew they were kind of crap (a lot of us were using coffee filters stapled onto the masks to increase its effectivenes…

Could you share a link for $1 N95's? That's better than I've seen. I've already moved to this approach myself, it's an increase in cost that I'll gladly take for increased protection. Just waiting for government and businesses in the US to catch up.

It was definitely hard to find the good stuff at first - and I was much more reclusive as a result too - but yeah, things have changed.

I wish people wouldn't respond to changes in policy/advice as evidence of "lying" before, as much of it has just been learning more. (Though the "we're gonna tell people they're ineffective because we want to reserve them for professionals" thing was a huge unforced error, IMO.)

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#29

Post by jerf » Fri, Sep 03, 2021, 6:05 PM UTC

cfn wrote: post #23

dragontamer wrote: post #2

> The researchers enrolled nearly 350,000 people from 600 villages in rural Bangladesh Wow. I was about to complain about "small n", but... an experiment of this size is not small at all. Congrats on the researchers on doing such a big study!

I think it is a bit cheeky of them. They promoted the usage of masks and distancing in 600 villages totalling 350,000 people and observed the results (mask wearing plus distancing) in mosques (by sampling, not by checking each individual).

I know it's easy to get cynical about "sampling" when you see a stream of studies sampling populations of millions with n = 12 and getting p values just barely considered "significant", but that's not the fault of "sampling". That's just... gathering no data, basically, or if you prefer, going through the motions of gathering data without actually doing it.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#30

Post by dragontamer » Fri, Sep 03, 2021, 6:05 PM UTC

nielsbot wrote: post #24

dragontamer wrote: post #18

Earlier quoted context omitted.

I think most of us got cloth masks with the full expectation that they were worse than proper PPE from hospitals (be it surgical masks or N95 masks). I'm not sure if people remember: but there was a shortage of masks of all kinds in March 2020. Cloth masks were the only thing we could get, and we all knew they were kind of crap (a lot of us were using coffee filters stapled onto the masks to increase its effectivenes…

Seems quite reasonable to wear a (K)N95 instead of a surgical mask. Slightly less comfortable, but yes, affordable for most.

That "K" means that my ears hurt after 2 hours though.

Going for full N95 means that the strap goes all the way around my head and is way more comfortable for extended use (ex: airplane rides or whatnot)