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

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

#211

Post by proc0 »

Volundr wrote: post #207
proc0 wrote: post #199

Earlier quoted context omitted.

Why not lockdown forever, and everyone social distance and isolate? We CAN do that right?

> Why not lockdown forever, and everyone social distance and isolate? We CAN do that right? Can we? I mean a lock down has economic consequences that I just don't see from mask use. Maybe technically it's possible, but one of these things is not like the other. I'm not advocating for permanent mask use. I'm not even advocating particularly hard for mask use in general right now (I mean we probably should). I'm not ad…

I'm not really arguing in favor of it... the point was we shouldn't just do something permanently because it reduces risk and it's possible. It's absolutely possible to adapt everyone into long term lockdowns, and I believe parts of Australia are in this right now, but we can clearly see that it is a bad idea.

> But I keep seeing mask use being presented as some great hardship, that can only be born briefly (if at all) and I just don't see it.

In my opinion, it's not being done consistently in a way that makes sense. It's at best a lazy rule to make everyone behave the same way. Not everyone is spreading the virus, so it follows not everyone should wear one, yet there are zero attempts at factoring this in to mandates. It's everyone regardless of health.

Again, at best it's a lazy implementation that enables authorities to do blanket power grabs instead of creative solutions that work not just for the vulnerable but also the majority of people who are already protected in some way.

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

#212

Post by Marsymars »

gunapologist99 wrote: post #150
kragen wrote: post #104

Earlier quoted context omitted.

Given a really effective intervention for a contagious disease, the effectiveness on a community level will be much lower on an individual level. Think about PRC vs. USA: 4636 deaths in PRC, 618591 deaths in USA, even though it's a four times smaller country. There is no measure that even comes close to reducing your risk of death from covid by a factor of 600 on an individual level, but because they were able to get…

> 4636 deaths in PRC That number is completely laughable. It's literally communist propaganda.

I have no particular insight into that particular number, but it isn't believable that covid has been broadly circulating in China uncontrolled for the past two years, and there isn't much middle ground between "uncontrolled spread" and the media-reported state of affairs.

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

#213

Post by kragen »

908B64B197 wrote: post #115
kragen wrote: post #104

Earlier quoted context omitted.

Given a really effective intervention for a contagious disease, the effectiveness on a community level will be much lower on an individual level. Think about PRC vs. USA: 4636 deaths in PRC, 618591 deaths in USA, even though it's a four times smaller country. There is no measure that even comes close to reducing your risk of death from covid by a factor of 600 on an individual level, but because they were able to get…

> Think about PRC vs. USA: 4636 deaths in PRC, 618591 deaths in USA, even though it's a four times smaller country. 4636 deaths as reported by the CCP to foreign journalists. Same party whose official line is that nothing happened in Tiananmen Square.

This is nonsense, partisan propaganda masquerading as rational thought. Nevertheless, there are many countries that had similarly effective infection control, so even if you choose to believe your hate for China instead of the best unbiased assessments, check out New Zealand, Vietnam, ROC, Thailand, or Australia.

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

#214

Post by derbOac »

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…

FWIW, there was also an effect of mask color. It seems like a trivial detail and in a lot of ways it is, but it kinda points to compliance as a factor and, in turn, factors influencing compliance.

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

#215

Post by timr »

GeekyBear wrote: post #128
timr wrote: post #62

Earlier quoted context omitted.

> Widespread mask use came as close to wiping out last year's Flu season as we've ever seen. This is an assertion. It could have been the fact that nobody was traveling last year. It could have been the fact that most kids were out of school. It could have been distancing. It could have been any number of other things. Any conclusion here is premature.

The conclusion that cloth masks are ineffective against viruses with an airborne spread, while a properly worn n95 mask does provide real protection is hardly premature. Here's the quote above from one of the scientists on President Biden's Covid advisory board in context: >Needless to say, masking is political hot button beyond anything I've ever seen in public health. At the same time i think we've all done a disse…

> The conclusion that cloth masks are ineffective against viruses with an airborne spread, while a properly worn n95 mask does provide real protection is hardly premature.

You're just asserting it to be true, so yes, it is.

> I've been really disappointed with my colleagues in public health for not being more clear about what can masking can do or not do.

I agree with this, but probably not for the reason you're saying it. It's hard to "be clear about what masking can do", when you haven't actually bothered to gather any evidence for it, one way or the other.

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

#216

Post by timr »

slg wrote: post #161
timr wrote: post #51

Earlier quoted context omitted.

> That number will be much higher since as you said a number of people didn't/don't comply at a societal level. ...or it will be lower. The study confounds the effects of distancing and mask-wearing. Distancing was higher in the surgical mask cohort. Also, as others note, the confidence interval for the surgical mask group overlaps zero. You can't rule out that the observed effect is due to chance.

From the study: >The intervention increased proper mask-wearing from 13.3% in control villages (N=806,547 observations) to 42.3% in treatment villages (N=797,715 observations)... Physical distancing increased from 24.1% in control villages to 29.2% in treatment villages Mask wearing increased 218% while distancing increased by 21%. I agree this is not proof specifically about masks, the study is about specific public…

> Mask wearing increased 218% while distancing increased by 21%.

You can't just compare "percentage change" of two wildly different things, and leap to the conclusion that the magnitude of change is causal. It begs the entire question: if physical distancing works well, and mask wearing does not work, you could increase mask wearing by whatever percentage you like, and a smaller change in physical distancing would still overwhelm it. We don't know.

But aside from that, you skipped over an important part of what I said: distancing was higher in the surgical mask group. See Table 2.

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

#217

Post by timr »

clairity wrote: post #208
YZF wrote: post #198

Earlier quoted context omitted.

I'm not talking about model studies. I am talking about case studies, like: https://www.nytimes.com/2020/04/20/health/airflow-coronaviru... Also: https://www.the-scientist.com/news-opinion/ferret-study-rein... Even early on with the Diamond Princess you've seen wide spread of the virus despite passengers being largely confined to their cabins. There were multiple other examples. We also know the Delta variant is more…

the diamond princess is especially poor evidence, as it was an after-the-fact investigation (with heavy motivation to find something and gain early notoriety), not a study per se . what likely happened was that there were multiple social infection vectors (not of the long-distance air variety but more the drunk chatting variety) and the crew and passengers distorted their testimony to limit their own liability exposu…

The diamond princess people also ate their meals in a shared space, IIRC. I think they changed that eventually, but by the time they did, the conclusion was hopelessly confounded.

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

#218

Post by timr »

slg wrote: post #81
timr wrote: post #67

Earlier quoted context omitted.

They did all of those things, but this paper is about the effect of mask-wearing (surgical vs. cloth vs. none) on the rate of symptomatic seroprevalence in the groups. Kuldorff is right, and is just stating the top-line numbers from the paper.

>Free mask distribution and promotion reduced the proportion of people who reported COVID-like symptoms on average by 11 percent, which was driven mainly by the effects of surgical masks. Villages where cloth masks were distributed experienced a 5 percent reduction in symptoms, while villages where surgical masks were distributed saw a reduction of 12 percent. About a third (40 percent) of those who reported COVID-19…

> There is nothing in this report about the effectiveness of masks on an individual level.

The DANMASK RCT [1] provided a direct test of masks as personal protective equipment, and found no support for masks. The criticism of that study, at that time, was that it didn't test the hypothesis of protecting others. So here we have an RCT that tests that hypothesis, and now that's not good enough, because the results aren't "at an individual level"?

Boy, the ground sure is slippery around here!

[1] https://www.acpjournals.org/doi/10.7326/M20-6817

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

#219

Post by BobJackienine »

It wasn't the mask wearing it was the distancing when I was in the military mission oriented personal protection taught us never to issue surgical masks when they're touched they're contaminated and need to be thrown out.

ITT: either this place is turned into Reddit with a bunch of retards bots or none of you can read statistics or can even do basic math.

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

#220

Post by Scoundreller »

blub wrote: post #192
Scoundreller wrote: post #89

Earlier quoted context omitted.

I’m not quite at that point of “fuck it, I’m vaccinated, come at me”, but I have to travel soon and the country I’m transiting through (Iceland) now requires a test. I’m nervous about it because I’m vaccinated, so I very well could have a mild infection and not know it, and get denied boarding and quarantined at home. At least it’s an antigen test and those miss most non-symptomatic infection anyway.

Or you could test yourself daily at home before your departure day and remove the element of surprise.

But a positive test isn't forever. I could test positive today (and disqualify myself for 2 weeks) while I could test negative next week.

Plan was to lay low for the couple weeks before departure.

Self-tests are hard to come by here.

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