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Old 07-08-2020, 06:53   #331
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Re: Just when I thought I knew something

Assuming this dystopian future could last and last we wear 3M cartridge filtered masks. I cannot smell solvent wearing it. If I were to wander into a peaceful demonstration only my eyes would inform me that the haze was actually tear gas.
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Old 07-08-2020, 07:17   #332
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Re: Just when I thought I knew something

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Originally Posted by Capn Jimbo View Post
Re: Mask Effectiveness

Yes and a really good question.

The reasons masks are surprisingly effective are these. First it is important to note that the virus is carried in relatively large droplets (think like a cough) which the mask CAN stop and/or slow to a large degree. There are also aerosols - micro droplets - which are also stopped to a degree, but almost more importantly those particles lose velocity.

For example an uncovered mouth can direct droplets to travel up to 12 feet, even beyond the widely recommende, d 6 feet or 2 meters. Even simple masks can reduce that distance to inches.

There has been studied for many years and is reliable. Masks absolutely reduce transmission of respiratory viruses very significantly.
Well, there's obviously some debate about this (see e.g. the recent flare-up in Japan noted above), but btwn the public health experts touting their effectiveness and wearing them not being unduly burdensome, I believe it is prudent to wear them, at least in indoor public spaces. I also think it makes sense for grocery stores, etc. to require them. Your conclusions about their effectiveness could be absolutely correct, but I don't think the matter is as certain as you suggest.

But my question really went to why you are posting a graph about masks restricting the breathing in of air pollution particulates when we're discussing their effectiveness at restricting the transmission of microscopic viruses. I think everyone understands the rationale concerning droplets of various sizes, and the idea that the more restrictive the mask the greater the potential, but do you have medical evidence closer to what we're dealing with here? You stated previously that 90+% mask use alone would stop the pandemic. We certainly don't need absolute scientific certainty for people to redouble their efforts at mask usage and social distancing, but the weight you've been giving to the effectiveness of mask usage suggests that some of the more draconian measures may not have been necessary.
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Old 07-08-2020, 08:28   #333
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Re: Just when I thought I knew something

Our ability to control a virus without a vaccine is a myth:

https://www.realclearpolitics.com/ar...cs_143899.html
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Old 07-08-2020, 09:31   #334
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Re: Just when I thought I knew something

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Originally Posted by Capn Jimbo View Post
Re: Mask Effectiveness
The reasons masks are surprisingly effective are these. First it is important to note that the virus is carried in relatively large droplets (think like a cough) which the mask CAN stop and/or slow to a large degree.
Liquids have the pesky habit of evaporating. What happens to the virus at that point? Do we know if it sticks to the mask? Does it pass through at that point? Does the virus live for a few hours before desiccation destroys it? How do we know a mask can stop it? Has someone tested using a test material that is suspended in an aerosol?

Quote:
Originally Posted by Capn Jimbo
For example an uncovered mouth can direct droplets to travel up to 12 feet, even beyond the widely recommende, d 6 feet or 2 meters. Even simple masks can reduce that distance to inches.
The dispersion distance is immaterial. No one goes into a grocery store only to remain motionless. You have to walk through areas that other people have breathed in. If someone with the measles goes into a room and leaves, others can be infected just by walking into that room up to 2 hours later.

Quote:
Originally Posted by Capn Jimbo
There has been studied for many years and is reliable. Masks absolutely reduce transmission of respiratory viruses very significantly.
Masks are so reliable that the CDC recommended NOT wearing masks at the outbreak of Covid. It's proven science! Where have I heard that before?

Masks do reduce transmission ... just to an undetermined degree. If masks were hugely successful then countries with a near 100% compliance rate, like Japan, wouldn't be seeing a huge resurgence. Masks have been required in New York since April but every monthly seroprevalence survey since then has seen increases of hundreds of thousands of people. How?

Masks are part of the solution but my educated GUESS is that they are not anywhere close to 50% effective.
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Old 07-08-2020, 13:34   #335
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Re: Just when I thought I knew something

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What happens to the virus at that point? Do we know if it sticks to the mask?

Yes.

Does it pass through at that point?

That would depend on the mask, but on average perhaps 20-30% leaks. The little that passes through is greatly reduced, and at much lower velocities.

Does the virus live for a few hours before desiccation destroys it?

Probably.

How do we know a mask can stop it? Has someone tested using a test material that is suspended in an aerosol?

Numerous studies over many years, done by 3M, and many research studies. Even ordinary surgical masks were shown to be as effective as high end N-95 hospital masks in greatly protecting against the ordinary flu virus.

The dispersion distance is immaterial.

Dispersion distance is absolutely critical. An open mouth (no mask) spreads tremendous amounts of droplets and micro-droplets for up to 12 feet, even though recommended distancing today is about 6 feet or 2 meters. Even a cheap mask reduces dispersion to inches, and remains at low velocity. Whatever and whereever the risks exists, masks reduce the risk signficantly.

Risk is never eliminated. Remember that masks are just one of about 100 factors that go into controlling the virus, and with the goal of keeping the numbers low enough to TTQ (test, trace and quarantine). At that point life becomes much more normal.

No one goes into a grocery store only to remain motionless. You have to walk through areas that other people have breathed in. If someone with the measles goes into a room and leaves, others can be infected just by walking into that room up to 2 hours later.

Closed spaces require many other interventions, but masks help in any venue. Of course the more persons, the closer the distance, the extent of the enclosure. the type, direction and design of the ventilation, the filtering, virus cleaning type and frequency, etc. The factors are many. Regardless, whatever the risk factor, the masks will result in a significant reduction of risk. Period.

Masks are so reliable that the CDC recommended NOT wearing masks at the outbreak of Covid. It's proven science! Where have I heard that before?

That is a political question. At the outset, there were very few known infections in very limited areas. There was panic however and there was a rush on masks and stockpiling, and limited production of PPE, thus putting the front line nurses and doctors at great risk and with far greater likelihood of encountering the virus. This was NOT a matter of mask effectiveness - your implication - but of supply shortages for health workers vs public demand vs very little virus.

Masks do reduce transmission ... just to an undetermined degree.

The scientific consensus is well established and determined to be in the range of around 80-90% reduction in risk. Even masks alone are FAR better than what the US is doing now, but don't forget the 100 other factors that play an important part in controlling the virus.

If masks were hugely successful then countries with a near 100% compliance rate, like Japan, wouldn't be seeing a huge resurgence.

Not so. Again, mask compliance is one of about 100 other important factors considered in the relative effectiveness of a country's protocol. Most countries to date have mixed protocols and mixed factors. Japan does NOT demonstrate 100% compliance; indeed they have loosened up, perhaps due to exhaustion or other factors I'd guess. No country has.

Masks have been required in New York since April but every monthly seroprevalence survey since then has seen increases of hundreds of thousands of people. How?

I have no idea where this comes from, better cite it. The number I do know is that NY's postive test rate (of new tests given) is down to 1%, the best by far in the US and possibly in the world. Anything at 3% or lower is the standard for Covid control. The failing states are testing at say 15 to even 20% (!) which is the main indicator of uncontrolled spread (meaning that the testing is inadequate, and many more cases of undiscovered Covid are out there in those failing places).

Masks are part of the solution but my educated GUESS is that they are not anywhere close to 50% effective.

That's simply not true. Average is 80% with some leakage, N-95's to 90% with less leakage. Double layer home made masks are surprisingly effective. As shown a few pages back even the very worst mask at 50%, with the compounding effect of both parties masked, and in consideration of the dose/response curve result in an overall reduction beginning at around 90%. Naturally, long periods of exposure, even with masks, increase the risk (think nurses).

Answers above.
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Old 07-08-2020, 16:13   #336
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Re: Just when I thought I knew something

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Originally Posted by fatherchronica View Post
Assuming this dystopian future could last and last we wear 3M cartridge filtered masks. I cannot smell solvent wearing it. If I were to wander into a peaceful demonstration only my eyes would inform me that the haze was actually tear gas.
Just a reminder that CV can and does enter the body via the eyes as well or so I'm have been told.

Of course this does not take anything away from the importance of wearing masks.
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Old 07-08-2020, 19:22   #337
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Re: Just when I thought I knew something

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Even better would be to wear gloves; and I guess we will start to see more and more of that.

Eeerrrrnh!!! WRONG!!

Gloves collect 'transfer particles' and ... umm transfer them....

This principle is why you see surgeons holding both hands up after fitting gloves - precisley so they don't touch ANYTHING and then transfer that to the patient.

Gloves are a bad idea unless you're changing them "every patient", ushc as *should* be happening at testing stations but doesn't.

In those cases, it is actually protecting the wearer, not the patient! As any COVID particels are then dumped when the gloves are removed.

There has been some statements here in COVID Safe Training about NOT touching hand to face even when wearing a mask, as this can cause transfer.

So, as masks were originally not the "panacea", neither can gloves be said to be so.

Useful for some, seriously useful for tohters, but for general use, tricky....

Usage requires extreme self discipline. For the average punter, that is...
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Old 07-08-2020, 23:26   #338
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Re: Just when I thought I knew something

I can't believe people can be dumb enough to wonder why WHO, CDC, and everyone else recommended not wearing a mask back in February, March, April. It would have been total chaos and there would have been far more infections and deaths among healthcare workers if the whole world was buying and stockpiling PPE for their own use.
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Old 07-08-2020, 23:41   #339
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Re: Just when I thought I knew something

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Tomfl-I think you had the wrong heading. It should have been " Just when I new nothing"! Japan has over 35,000 cases! Taiwan has only approx. 425 and Vietnam has less than 400 total cases. Their knocking it right out of the park. Better do a little more homework next time.
A couple weeks ago vietnam had zero death....mind blown. Even if you don't believe the numbers it has to be close. https://www.cnbc.com/2020/07/23/viet...us-deaths.html

I've been in China since the start and know people who was stuck in Wuhan during the worst of it. From what I have seen and heard the numbers are not too far from the truth. This is partly because everyone is tracked using their phone which is a good idea during a pandemic. Personally if you are not doing anything illegal I have no problem letting the government known where I am or what i'm doing.
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