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Tags Coronavirus , vaccine

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Old 14th January 2021, 10:43 AM   #361
Bob001
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Early reports of J&J vaccine looking good.
https://www.msn.com/en-us/news/polit...nt/ar-BB1cKM0O
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Old 14th January 2021, 10:43 AM   #362
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Originally Posted by Klimax View Post
What sun? (Central Europe here...)
Lol. Here in the USA people think of Italy as being nearly tropical and don't realize that it's further North than the large majority of the USA excluding Alaska of course.
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Old 14th January 2021, 11:44 AM   #363
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I remember friends in Michigan being gobsmacked to realise that where I live is at the same latitude as the middle of the Hudson Bay.
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Old 14th January 2021, 11:47 AM   #364
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Originally Posted by marting View Post
Lol. Here in the USA people think of Italy as being nearly tropical and don't realize that it's further North than the large majority of the USA excluding Alaska of course.
The difference is that Italy is surrounded by the Mediterranean. Most of Italy really is warmer than comparable latitudes in, say, Nebraska. London is far north of Montreal, but the winters are hardly comparable.
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Old 14th January 2021, 12:30 PM   #365
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Originally Posted by Bob001 View Post
The difference is that Italy is surrounded by the Mediterranean. Most of Italy really is warmer than comparable latitudes in, say, Nebraska. London is far north of Montreal, but the winters are hardly comparable.
True. Gulf stream and Mediterranean helps a lot temperature wise. Doesn't do much for sunlight though.
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Old 14th January 2021, 12:35 PM   #366
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Anyone run across vaccine efficacy in the weeks subsequent to vaccination? I would expect the first effects within a week or two would be reduction in severity with longer periods before infection prevention occurs for most.

With the millions of doses and the high rate of community spread there should be an absolute wealth of data on the vaccines in wide use far exceeding phase 3 trials. This data should be of use in fine tuning vaccine distribution policy. Where is the data?
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Old 14th January 2021, 01:08 PM   #367
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protease inhibitors; cocktail, anyone?

Here is a link to an introduction on whether or not protease inhibitors will be effective against this disease. Proteases are enzymes that hydrolyze peptide bonds, and a particular peptide bond must be cleaved for the virus to enter the cell. IIUC there are both viral and host (cathepsins B and L) cysteine proteases that might be inhibited. There is a third host protease, Transmembrane serine protease 2 (TMPRSS2), that is a serine protease.

Some of the tested compounds are repurposed, which IMO is good in some ways. At the active site of many proteases, a cysteine or a serine residue forms a temporary covalent bond with the normal substrate. Some inhibitors are covalent: they mimic the normal reaction but remain permanently bound to the protease. Some covalent warheads (reactive chemical groups) that are effective against cysteine proteases are much less effective against serine proteases, or at least show different reactivity.

The author wrote, "However, a new study, released on the bioRxiv* server in November 2020, draws attention to the high odds that these may not have anti-infective activity because of the redundant pathways present in human host cells...Earlier protease inhibitors targeting other RNA viruses have been difficult to develop, and this could predict similar obstacles in the path of the current attempt." My speculation is that inhibition of proteases might require a cocktail format involving two or three protease inhibitors.
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Old 14th January 2021, 02:05 PM   #368
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Originally Posted by Bob001 View Post
Early reports of J&J vaccine looking good.
https://www.msn.com/en-us/news/polit...nt/ar-BB1cKM0O
Good news tempered with astonishment that they only figure on having 12 million doses available by the end of April.

That seems remarkably low compared to other vaccines.

Originally Posted by marting View Post
Anyone run across vaccine efficacy in the weeks subsequent to vaccination? I would expect the first effects within a week or two would be reduction in severity with longer periods before infection prevention occurs for most.
Still very early in the piece, but there's some news from Israel, with a couple of points:

First Pfizer shot curbs infections by 50% after 14 days That's probably good, given the second injection should raise the protection considerably.

but...

Seventeen percent of the new serious cases today, or 180 cases, are after the first dose

Emphasising the fact that the vaccine takes time to become fully protective, and I'm picking a lot of people thought "Hooray, I'm vaccinated and Covid can't catch me!"
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Old 14th January 2021, 03:10 PM   #369
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Originally Posted by The Atheist View Post
Still very early in the piece, but there's some news from Israel, with a couple of points:

First Pfizer shot curbs infections by 50% after 14 days That's probably good, given the second injection should raise the protection considerably.

but...

Seventeen percent of the new serious cases today, or 180 cases, are after the first dose

Emphasising the fact that the vaccine takes time to become fully protective, and I'm picking a lot of people thought "Hooray, I'm vaccinated and Covid can't catch me!"
Yeah!

OTOH, Approx. 50% reduction in positive tests after 15 days from the first shot is decent. I'd like to see the stats on those that did test positive and how the disease progressed in them.

But gotta hand it to Israel. 20% of the population and 73% of those over 60 already vaccinated! They are way ahead of any other country.

"“Seventeen percent of the new serious cases today, or 180 cases, are after the first dose,” she told reporters."

Need more info. When did they receive the vaccine? How many days after did they show symptoms? How many days after did they test positive? When did they become "serious"? How does this compare with similar numbers that test positive?

Hard to assess without the data. And they do have the data.
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Old 14th January 2021, 04:25 PM   #370
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Meanwhile, the 2,000,000 deaths has been passed.

Little surprise that the top 5 countries, all run by nutcase extreme-right leaders, make up 50% of the deaths.
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Old 14th January 2021, 06:48 PM   #371
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South Korean drug manufacturer Chong Kun Dang is claiming that its version of nafamostat mesylate looked effective in a phase 2 clinical trial:

Quote:
The clinical phase 2 trial on Napabeltan, which was conducted in Russia on some 100 patients with a serious case of COVID-19, showed a 61.1% improvement in symptoms on high-risk patents, superior to 11.1% for standard treatment group. Over the 28 days of test period, the symptom improvement rate with napabeltan was as high as 94.4% overshadowing the 61.1% of improvement rate for the standard treatment group.
Quote:
Notably, four patients died among the standard treatment group when no death occurred in the napabeltan treatment group.
https://www.donga.com/en/article/all...linical-trials
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Old 15th January 2021, 12:21 AM   #372
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Originally Posted by TellyKNeasuss View Post
South Korean drug manufacturer Chong Kun Dang is claiming that its version of nafamostat mesylate looked effective in a phase 2 clinical trial:





https://www.donga.com/en/article/all...linical-trials
https://www.immunology.ox.ac.uk/covi...peutic-effects

A more technical review of action.
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Old 15th January 2021, 01:08 AM   #373
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Now we have a new Brazilian strain, which is very similar to the Saffer strain: https://www.bbc.com/news/live/world-55673006

Given the number of infections worldwide, it's no surprise the mutations are coming through so frequently.

Gotta say, I don't get the best feeling about this - there will be new mutations at least every month and it seems to me it's only a matter of time before one of the mutations is enough of a shift to negate vaccines.
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Old 15th January 2021, 02:45 AM   #374
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And to keep with the disturbing news, lots of countries in the sub-Saharan Africa are showing deeply concerning spikes: Zambia. Zimbabwe, Nigeria, Malawi, D R Congo and Namibia have all started having massive spikes in the last week. That has to be the SA strain at work.

I also see that Cuba, having done so well for so long, has had a very sharp increase in cases to way above previous records. Given their friendly relations with Brazil, it wouldn't surprise to me to see the Brazilian strain there.

Looks like things will get worse before they get better.
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Old 15th January 2021, 10:42 AM   #375
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Donated antibodies / plasma is of no benefit.
https://www.bbc.co.uk/news/health-55681051
Probably an important thing to prove given how resource intensive this treatment was.

Currently best evidence is for cheap dexamethasone and more expensive tocilizimab if seriously ill. Remdesivir no longer in fashion. I would be interested to find out how much profit was made from this useless drug.

Nafamostat above looks interesting, logical mechanism of action, proven effect in vitro with viral culture and phase 2 study a reasonable size and sounds promising. One caution is that this is a bit of a dirty drug. It also acts as an anticoagulant and we know blood clots are an issue in covid, it may be just its blood thinning action that is of benefit not the theoretical anti-viral action.
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Old 15th January 2021, 11:30 AM   #376
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Originally Posted by The Atheist View Post
Now we have a new Brazilian strain...
And a new Ohio strain.

https://www.cbsnews.com/news/new-cov...in-found-ohio/

They're all slowing remarkably similar changes, which suggests it's being driven by evolutionary pressure.

Urgent work needed!
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Old 15th January 2021, 12:45 PM   #377
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I know of no way "evolutionary pressure" can influence what mutations actually happen. As far as I know the mutations are random, and then natural selection favours the ones that spread most easily.

Lots of virus = lots of mutations though. And the more mutations the likelier it is that unpleasant ones will happen.
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Old 15th January 2021, 07:09 PM   #378
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I want to ask a sciency question about PPE.


Why are single use masks single use?

I get that they can't be washed, but assuming they aren't damaged, couldn't I take one off, let it sit for a week, and then reuse it perfectly safely?

It may be that the virus lives longer than a week on paper, I suppose, but there has to be some sort of time limit on how long they last, and maybe if they're hit with UVC or something? Are they actually single use, or is it simply that the manufacturers do not trust the user to keep them away from use for long enough for the bugs to die out between uses?
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Old 15th January 2021, 07:30 PM   #379
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Originally Posted by Meadmaker View Post
I want to ask a sciency question about PPE.


Why are single use masks single use?

I get that they can't be washed, but assuming they aren't damaged, couldn't I take one off, let it sit for a week, and then reuse it perfectly safely?

It may be that the virus lives longer than a week on paper, I suppose, but there has to be some sort of time limit on how long they last, and maybe if they're hit with UVC or something? Are they actually single use, or is it simply that the manufacturers do not trust the user to keep them away from use for long enough for the bugs to die out between uses?
I'm not aware of anything specific that's been published on this but I recycle masks. When I go out to the post office (mail isn't delivered where I live) or occasional shopping and get back, I put the mask aside. I probably use masks no more than 10 minutes a day on average. I rotate between 3 masks so there's 3 or more days between use and replace them all every 3 weeks.
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Old 15th January 2021, 07:58 PM   #380
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Originally Posted by Meadmaker View Post
I want to ask a sciency question about PPE.

Why are single use masks single use?

I get that they can't be washed, but assuming they aren't damaged, couldn't I take one off, let it sit for a week, and then reuse it perfectly safely?
You can find studies showing that performance of surgical masks starts to decrease significantly after a few hours. If you're wearing one for ten minutes at a time, you should be fine with 15 uses each or so.

I leave mine on the dashboard of my car for a few weeks, thinking the sun and heat (I'm in Florida) will help in addition to the time. I suppose the windshield blocks most of the UV though.
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Old 15th January 2021, 08:20 PM   #381
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Originally Posted by Meadmaker View Post
I want to ask a sciency question about PPE.
Why are single use masks single use? ... snipped a bunch of stuff....

You have to say which mask. There is no one answer.
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Old 16th January 2021, 02:51 AM   #382
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Originally Posted by The Atheist View Post
First Pfizer shot curbs infections by 50% after 14 days That's probably good, given the second injection should raise the protection considerably.

but...

Seventeen percent of the new serious cases today, or 180 cases, are after the first dose

Emphasising the fact that the vaccine takes time to become fully protective, and I'm picking a lot of people thought "Hooray, I'm vaccinated and Covid can't catch me!"
The 50% number is misleading. As you can see from the data in the New England Journal of Medicine article here (look at the graph on the second last page) there is little to no protection for around 10 days, then pretty strong protection from day 10 to 21. Beyond that it's not clear because the trial participants got the second dose. But it seems 85% effectiveness of the first dose from 10 days onwards is a conservative estimate.

Of course it's not clear how long that lasts without the second dose.

Basically, any numbers based on cases since the first dose that don't exclude the first few days will be too pessimistic.
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Old 16th January 2021, 07:04 AM   #383
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There are some reports of deaths from side effects of the vaccine among the frail and elderly.

https://norwaytoday.info/news/norweg...l-and-old/amp/

Quote:
Norwegian Medicines Agency links 13 deaths to vaccine side effects. Those who died were frail and old
Unfortunately that's the same group most likely to die from Covid.
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Old 16th January 2021, 07:33 AM   #384
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Originally Posted by Meadmaker View Post
Why are single use masks single use?

I get that they can't be washed, but assuming they aren't damaged, couldn't I take one off, let it sit for a week, and then reuse it perfectly safely?

It may be that the virus lives longer than a week on paper, I suppose, but there has to be some sort of time limit on how long they last, and maybe if they're hit with UVC or something? Are they actually single use, or is it simply that the manufacturers do not trust the user to keep them away from use for long enough for the bugs to die out between uses?

I don't know anything about surgical masks, never used them.

I have been using FFP3 masks in exactly that way since the pandemic began. I had two old ones in the house from 2010 (filched from work when the H1N1 pandemic-that-wasn't was threatened), which were a bit ratty, but were all I had. I used them turn about, leaving them to dry on a radiator between uses. Some uses were only five or ten minutes, occasionally an hour or so. I didn't go out on consecutive days and sometimes I didn't go anywhere for a week or more.

I can't know how effective this was (although I didn't catch anything) but it seemed the best way to use them. They're primarily rated as dust masks and the main issue (reading the instructions) seems to be clogging. However if you're using them to screen moisture droplets and not dust I don't see why they would clog and drying them out in my view ought to restore functionality.

It's not about the virus persisting on paper, which it doesn't really (a couple of days on a radiator is going to see anything off), it's about the functionality of the filter.

Of course when supplies are plentiful you use one for a shift then chuck it away. But when you can't get any more then you have to make the best of it.

After about eight months of this I was able to buy another 15 masks, so I discarded my two old faithfuls. I'm still just using the first of the new lot, and I have also given away another four to friends, with instructions to use them for shopping and in any other enclosed public space, as I described, drying them on a radiator when not in use. I figure they'll be no worse than the non-filtered face coverings we see in regular use, and probably enormously better.

I believe in South Korea when this started there was a huge demand for similar masks and the government took control of supply and was allocating every individual citizen one mask a month. I presume they were making them last as I have described, and a month seems reasonable for one mask. Anybody know how South Korea is doing, nearly a year on?
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Old 16th January 2021, 09:06 AM   #385
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Originally Posted by Puppycow View Post
There are some reports of deaths from side effects of the vaccine among the frail and elderly.

https://norwaytoday.info/news/norweg...l-and-old/amp/



Unfortunately that's the same group most likely to die from Covid.
Don't panic.

Some numbers to ponder:
  • The nursing home population in Norway is just under 40,000
  • Per week, 400 people die in nursing homes in Norway under normal circumstances
  • Nursing home residents are being prioritized in the first round of vaccinations
  • Norway has so far administered about 30,000 shots
  • We may guess that 10,000 to 20,000 of those went to nursing home residents (the rest: staff, other old people)
  • So we can, assuming indiscriminatory administration of the vax, 100-200 deaths within a week of the shot without the vaccine doing any harm whatsoever
People who die usually have a host of symptoms, such as respiratory, gastro-intestinal, cardio, ...

One caveat: They would not give the vaccine to people already determined to be in the process of dying and on palliative care - don't know what percentae of people who die within a week would be in that exempted group

Anyway, point is: 23 people to die with any out of a host of mostly unspecific "symptoms" is less than totally expected.

It is not implausible that the stress of a severe reaction pushes the occasional frail person over the edge, but I am pretty sure that after close examination, significantly fewer than 23 deaths can be attributed to the vaccine.

On the other hand, that round of vaccinations is pretty much guaranteed to keep a lot more than 23 people from dying of Covid.
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Old 16th January 2021, 03:01 PM   #386
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Yet another study correlating low Vit. D levels with higher risk of covid death.

The Predictive Power of Serum Vitamin D for Poor Outcomes in COVID-19 Patients
https://icite.od.nih.gov/covid19/sea...rdId=rs-140417

With a binary determinative of "deficiency" at 20ng/dl, unders died at twice the rate of overs. That was about half the population of their covid patients.

From discussion:

According to our study, COVID-19 patients with vitamin D deficiency (a serum level of less than 20 ng/dl) were about twice as much at risk for ICU hospitalization and death, even after adjusting the statistical model for age and gender.
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Old 16th January 2021, 03:34 PM   #387
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Originally Posted by Meadmaker View Post
I want to ask a sciency question about PPE.

Why are single use masks single use?
Because before the PPE shortage and need to reuse them, they do not come with manufacturer instruction to disinfect and reuse them. There are non-disposable respirators with exchangeable cartridges. They are disinfected and reused.

Originally Posted by Meadmaker View Post
I get that they can't be washed, but assuming they aren't damaged, couldn't I take one off, let it sit for a week, and then reuse it perfectly safely?

It may be that the virus lives longer than a week on paper, I suppose, but there has to be some sort of time limit on how long they last, and maybe if they're hit with UVC or something? Are they actually single use, or is it simply that the manufacturers do not trust the user to keep them away from use for long enough for the bugs to die out between uses?
A lot of hospitals are disinfecting and reusing disposable respirators (masks).

Couple things that differ between use in and out of health care facilities. You can use your mask over and over if it is not damaged. But you should not share that mask with anyone else because they could get other infections from you.

The second issue is concern about the outer surface contamination with COVID. A mask is going to be heavily contaminated if used on a COVID ward as opposed to a lay person wearing it to the grocery store. So essentially you might be reading one guideline that differs from another because of the intended audience.

If it is kept in a warm dry place, sure you can use it again in a few days. I leave mine on the dashboard of my car parked outside because it gets both heat and UV rays. YMMV

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Old 16th January 2021, 03:40 PM   #388
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Originally Posted by Modified View Post
You can find studies showing that performance of surgical masks starts to decrease significantly after a few hours. If you're wearing one for ten minutes at a time, you should be fine with 15 uses each or so.

I leave mine on the dashboard of my car for a few weeks, thinking the sun and heat (I'm in Florida) will help in addition to the time. I suppose the windshield blocks most of the UV though.
That highlighted bit is directly related to the masks getting moist from one's exhaled breath. A moist or wet mask defeats the filtration ability, IOW the pathogens can slip right through a wet mask.
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Old 16th January 2021, 03:43 PM   #389
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Originally Posted by Oystein View Post
Don't panic.

Some numbers to ponder:
  • The nursing home population in Norway is just under 40,000
  • Per week, 400 people die in nursing homes in Norway under normal circumstances
  • Nursing home residents are being prioritized in the first round of vaccinations
  • Norway has so far administered about 30,000 shots
  • We may guess that 10,000 to 20,000 of those went to nursing home residents (the rest: staff, other old people)
  • So we can, assuming indiscriminatory administration of the vax, 100-200 deaths within a week of the shot without the vaccine doing any harm whatsoever
People who die usually have a host of symptoms, such as respiratory, gastro-intestinal, cardio, ...

One caveat: They would not give the vaccine to people already determined to be in the process of dying and on palliative care - don't know what percentae of people who die within a week would be in that exempted group

Anyway, point is: 23 people to die with any out of a host of mostly unspecific "symptoms" is less than totally expected.

It is not implausible that the stress of a severe reaction pushes the occasional frail person over the edge, but I am pretty sure that after close examination, significantly fewer than 23 deaths can be attributed to the vaccine.

On the other hand, that round of vaccinations is pretty much guaranteed to keep a lot more than 23 people from dying of Covid.
Thanks. My first thought was were these vaccine related or coincidental fatalities.

We'd be seeing a whole lot more fatalities if the mRNA vaccines were that dangerous.
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Old 16th January 2021, 04:16 PM   #390
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Originally Posted by Skeptic Ginger View Post
That highlighted bit is directly related to the masks getting moist from one's exhaled breath. A moist or wet mask defeats the filtration ability, IOW the pathogens can slip right through a wet mask.

That's not actually true as far as I know.
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Old 16th January 2021, 04:47 PM   #391
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Filtration effectiveness of wet masks is reportedly lower than that of dry masks

Of course, " reportedly " = anecdotal
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Old 16th January 2021, 04:57 PM   #392
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That's home-made cloth masks, not surgical masks. Mind you, I wouldn't rely on either to stop me catching anything.
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Old 16th January 2021, 05:36 PM   #393
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Why would a wet surgical mask be more effective than any home made cloth mask?

Home made masks can be effective if made properly..
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Old 16th January 2021, 06:08 PM   #394
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I don't know, and neither does that article. The article is only referring to cloth masks. I don't see why a wet mask of any sort would be less effective at trapping droplets or aerosols. There might be something mechanical about it touching the face perhaps, wicking the infected fluid across. Maybe.

Most of the expiry dates on PPE are nominal, and most of the "use once" injunctions are more about the purpose the item was manufactured for than actual performance potential. As I said, the limiting factor in the data sheets for the respirator masks is related to clogging of the filter, which depends a lot on what you're trying to breathe with it. If it's asbestos dust things are going to be a lot different from when it's aerosolised virus.
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Old 16th January 2021, 06:37 PM   #395
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Wet cloth masks are hard to breath through in the first place. As temperatures got bellow freezing here, it's really hard using them outside.
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Old 16th January 2021, 06:45 PM   #396
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Oh for pity's sake! This stuff is common sense. Surgical masks are not that different from cloth masks.

Moisture in a mask acts like a wick. Pathogens can move through the mask. And you the wearer are right up against that moisture so the organisms can contact your mouth and nose.

A dry disposable mask collects (and blocks) respiratory droplets in the air resulting in a filter ability that is a little better than just considering organism size and filtration effectiveness. If that wasn't so then no disposable mask could block virus sized particles.

As you breathe out, the mask collects your respiratory moisture in the same way. That's how it protects others from you the mask wearer. But when the mask gets wet it is less efficient at filtering, and vents more around the edges of the mask.


ETA: If I was trying to block smoke as I escaped a burning building or something, I'd want a wet towel. It makes a porous towel a better filter. And in that case I want the smoke to be blocked but I wouldn't worry about any wicking effect.

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Old 16th January 2021, 06:46 PM   #397
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Originally Posted by Rolfe View Post
I know of no way "evolutionary pressure" can influence what mutations actually happen. As far as I know the mutations are random, and then natural selection favours the ones that spread most easily.

Lots of virus = lots of mutations though. And the more mutations the likelier it is that unpleasant ones will happen.
Off topic but in bacteria there is a way that harsh environments encourage more mutations.

But as you say, that still doesn't target the mutations, just up the mutation rate when the organism is struggling, which increases the chance of a beneficial mutation occurring when it's not well adapted to its environment anyway.

And I can't see how that would happen in viruses.
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Old 16th January 2021, 06:47 PM   #398
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Thanks everyone for the replies. It sounds like I don't need to buy a new box of masks for a while.
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Old 16th January 2021, 06:57 PM   #399
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Originally Posted by Rolfe View Post
I don't know, and neither does that article. The article is only referring to cloth masks. I don't see why a wet mask of any sort would be less effective at trapping droplets or aerosols. There might be something mechanical about it touching the face perhaps, wicking the infected fluid across. Maybe.

Most of the expiry dates on PPE are nominal, and most of the "use once" injunctions are more about the purpose the item was manufactured for than actual performance potential. As I said, the limiting factor in the data sheets for the respirator masks is related to clogging of the filter, which depends a lot on what you're trying to breathe with it. If it's asbestos dust things are going to be a lot different from when it's aerosolised virus.
You are conflating masks that use charcoal or ionic filters that are used for chemical exposures. Those have a time limited use once you break them out of their sealed packaging.

For particulates, but not microorganisms, as long as you can breathe through a mechanical filtration mask, it's OK. The efficiency of keeping particulates out is simple: particle size vs filtration size.

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Old 16th January 2021, 06:59 PM   #400
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Originally Posted by Meadmaker View Post
Thanks everyone for the replies. It sounds like I don't need to buy a new box of masks for a while.
I've been using the same box of N95 masks all year. Started with 20. They are expired. That's fine since I'm not giving them to employees. But as I use them I can see that it's the elastic straps that are the problem. The more I stretch them getting them on, they get looser.
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