3 ms·

Completely agree that an ear loop is less effective than a headstrap. The question is: by how much? This beard length mask study is a good source of data. They

by graeme 3y ago

Completely agree that an ear loop is less effective than a headstrap. The question is: by how much? This beard length mask study is a good source of data. They actually measured fitted filtration efficacy at different beard lengths, including zero beard. N95 was near 100%. KN95 was between 80-90% (surprisingly, higher with a small bit of beard, around 0.5-1mm). Now, you could certainly argue that 80-90% filtration is performative, but on what evidence? We know from hepa filtration studies that lowering the concentration of virus in the air lowers infection amongst those in a room. So from physical mechanisms we would expect that reducing inhaled virus by 80-90% should likewise reduce risk of infection. https://pubmed.ncbi.nlm.nih.gov/34006963/#&gid=article-figures&pid=fig-2-uid-1 https://pubmed.ncbi.nlm.nih.gov/34006963/#&gid=article-figur...

tptacek 3y ago
I don't know! But in mandatory masking regimes, ordinary people do a clownish job of masking (and some of the masking rules are themselves clownish, as with the "mask until you get to the dining table, and then unmask as soon as the water arrived", which was very much the regime in Chicago when dining opened back up in 2021). The bigger point would just be to look at the epidemiology. I get that questioning masking pattern matches to COVID nihilism. I'm not a COVID nihilist. It was a big deal for me and I take it seriously. But the data I see suggests that the most significant bit in controlling it is ensuring people are vaccinated, and that most of the rest of the controls don't seem to do much.
- idlewords 3y ago
  One problem with "look at the epidemiology" as an approach is that the virus is such a moving target. I'm citing these figures from memory, so apologies if I mangle them, but with OG covid you could mask up properly and spend an hour in an enclosed space with viral particles in the air and have a low risk of infection, while with omicron you had maybe five minutes masked the same way before you'd catch an infectious dose. More generally, the trouble with evaluating masking is all the confounders. I spent the early pandemic in Japan, where ubiquitous masking was a highly effective barrier to spread. One reason it may have worked as well as it did is that people talked less with the masks on. But there were already strong social norms against talking in confined public places, and the public health authority stressed airborne spread. How much did that contribute? I feel like the mask issue is irretrievably lost at this point in the US, but it's important to stress that in places like Japan and Taiwan it worked quite well, at least until omicron got so infective that even stringent adherence was no longer adequate. But there's no way to untangle it from the changes in social behavior that accompanied it, some of them a physical result of the masks (less talking), some due to social signaling aspects of mask wearing, and many unrelated.
  - tptacek 3y ago
    Yeah, I thought I captured that but didn't. It's an important caveat; there was a much clearer case for masking in 2020-2021.

by graeme 3y ago

tptacek 3y ago

I don't know! But in mandatory masking regimes, ordinary people do a clownish job of masking (and some of the masking rules are themselves clownish, as with the "mask until you get to the dining table, and then unmask as soon as the water arrived", which was very much the regime in Chicago when dining opened back up in 2021). The bigger point would just be to look at the epidemiology. I get that questioning masking pattern matches to COVID nihilism. I'm not a COVID nihilist. It was a big deal for me and I take it seriously. But the data I see suggests that the most significant bit in controlling it is ensuring people are vaccinated, and that most of the rest of the controls don't seem to do much.

idlewords 3y ago
One problem with "look at the epidemiology" as an approach is that the virus is such a moving target. I'm citing these figures from memory, so apologies if I mangle them, but with OG covid you could mask up properly and spend an hour in an enclosed space with viral particles in the air and have a low risk of infection, while with omicron you had maybe five minutes masked the same way before you'd catch an infectious dose. More generally, the trouble with evaluating masking is all the confounders. I spent the early pandemic in Japan, where ubiquitous masking was a highly effective barrier to spread. One reason it may have worked as well as it did is that people talked less with the masks on. But there were already strong social norms against talking in confined public places, and the public health authority stressed airborne spread. How much did that contribute? I feel like the mask issue is irretrievably lost at this point in the US, but it's important to stress that in places like Japan and Taiwan it worked quite well, at least until omicron got so infective that even stringent adherence was no longer adequate. But there's no way to untangle it from the changes in social behavior that accompanied it, some of them a physical result of the masks (less talking), some due to social signaling aspects of mask wearing, and many unrelated.
- tptacek 3y ago
  Yeah, I thought I captured that but didn't. It's an important caveat; there was a much clearer case for masking in 2020-2021.