Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Low-cost measurement of facemask efficacy for filtering expelled droplets

advances.sciencemag.org

Post reply on HN
Print view View original

61–70 of 92 posts

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#61

Post by glofish »

zucker42 wrote: post #50
glofish wrote: post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

The question is whether I trust your "survey" or the CDC's recommendation. But also, in both cases based on a quick skim it seems to me like you're misrepresenting the studies. In the first study, the control was "normal practice" which included mask use. In the second study, I see no claims about cardiac damage; I understand it to say that masks make it harder to breathe, which is useful information but not very sur…

That is exactly right! What the paper says is that masks should be used when necessary and according to the case presented to the medical staff. Not all the time.

When you force people to use the masks all the time you are making the problem worse.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#62

Post by glofish »

asutekku wrote: post #49
glofish wrote: post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

We’ve also had studies which claim something along the line of ”Apples cause cancer” and the truth is that it happens only under some certain rare conditions and even then one might have 0.01% chance of increasing their chance to get a cancer by 0.1%. But hey, that’s an increase in possibility nevertheless!

the paper shows a tripling of cases when masks are used though, it is not about tiny percentages.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#63

Post by glofish »

zucker42 wrote: post #60
glofish wrote: post #58

Earlier quoted context omitted.

That is not what the paper found, all you need is to read the abstract: " Cloth masks also had significantly higher rates of ILI compared with the control arm " As for the second paper here is the summarry: " The increased breathing resistance is especially problematic for patients with chronic obstructive pulmonary diseases. Patients with diffusion disorders have reduced capacity to compensate due to the reduced tid…

The control arm included mask usage.

Indeed, the paper is so valuable exactly because it looks at what happens when you force people to use the masks all the time.

it turns out it might be making the problem worse

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#64

Post by xapata »

mannykannot wrote: post #38
throw_away wrote: post #31

Earlier quoted context omitted.

Which is damning in that they treated us like children who couldn't handle the truth and were also so unimaginative that they did not consider alternative face coverings.

There is now, and was then, plenty of evidence to suppose that enough people would not handle the truth responsibly, and would panic-buy masks rather than adopt alternatives.

Is the US government so impotent that it can't ask retailers to ship their supplies of masks to a commandeered warehouse? Of course some would go missing, but substantially all would arrive.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#66

Post by Nav_Panel »

glofish wrote: post #56
Nav_Panel wrote: post #45

Earlier quoted context omitted.

From first study: "The null hypothesis is that there is no difference between medical masks and cloth masks. ... The control arm was ‘standard practice’, which comprised mask use in a high proportion of participants [NOT "mask free"]." -- this means "increase relative to surgical masks", not relative to no mask. Second study is only N95s. Just don't wear an N95 if you need more air for aerobic capacity. The OP study…

not sure what your are getting at with the null hypothesis. Look at the results. Mandatory cloth masks were associated with 3 times as many ILIs (Influenza Like Illnesses). So it is not some tiny statistical variation. It is a huge effect size. As for the second study, it concludes:" The observed mechanisms may lead to more severe symptoms in individuals with impaired capacity for myocardial compensation. " I am talk…

> 3 times as many ILIs

Compared to surgical masks. There was no study of unmasked people. I expect it would be 10x.

> The observed mechanisms may lead to more severe symptoms in individuals with impaired capacity for myocardial compensation.

The study was only on N95 masks! Most people are wearing surgical or cloth, it's irrelevant.

> I am talking about how the all sources of information systematically downplay the negative effects and serious side effects of masks.

There appear to be very few, similar to how all sources downplay the negative effects of walking on the sidewalk vs walking in the road.

I would be a lot more sympathetic if you targeted your ire at "washing down surfaces", because that seems irrelevant with respect to spread. But masks work, and that's the long and short of it.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#67

Post by throw_away »

xapata wrote: post #64
mannykannot wrote: post #38

Earlier quoted context omitted.

There is now, and was then, plenty of evidence to suppose that enough people would not handle the truth responsibly, and would panic-buy masks rather than adopt alternatives.

Is the US government so impotent that it can't ask retailers to ship their supplies of masks to a commandeered warehouse? Of course some would go missing, but substantially all would arrive.

Quite the opposite: https://www.businessinsider.com/coronavirus-federal-govt-fem...

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#68

Post by macintux »

glofish wrote: post #61
zucker42 wrote: post #50

Earlier quoted context omitted.

The question is whether I trust your "survey" or the CDC's recommendation. But also, in both cases based on a quick skim it seems to me like you're misrepresenting the studies. In the first study, the control was "normal practice" which included mask use. In the second study, I see no claims about cardiac damage; I understand it to say that masks make it harder to breathe, which is useful information but not very sur…

That is exactly right! What the paper says is that masks should be used when necessary and according to the case presented to the medical staff. Not all the time. When you force people to use the masks all the time you are making the problem worse.

When people are violently objecting to wearing a mask for 10 minutes in the store, I’m less worried about studies focusing on long-term mask usage and more worried about the impact of those spreading doubt.

Re: Low-cost measurement of facemask efficacy for filtering expelled droplets

#69

Post by pfedak »

glofish wrote: post #43

The damages and side effects of masks are consistently and systematically downplayed. Benefits are vanishing if exist at all. The group think is such that you will never see any of these mentioned in the media. Here is a study that shows that cotton masks increase(!) the incidence of flu like diseases: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4420971/ And here is a study that warns that wearing masks leads to car…

The title of the first study is:

A cluster randomised trial of cloth masks compared with medical masks in healthcare workers

Not only is your presentation of its results in bad faith, you rely on people not reading the article.

Post reply on HN