COVID-19

[IlliniDave]

Sorry if this has been discussed, but 80 or 90 pages is a lot to try to read through ...

Yesterday the US CDC reversed course and apparently suggested folks wear masks of some sort while out in public. I have two of the disposable-type N-95 masks I bought when I was doing a bunch of sanding a while back. The masks I have are unused. I suspect I will not be able to get more. They were already gone from the home improvement hardware stores by the time I thought grabbing a couple would be a good idea. And I bought the Kool Aid that it was better to not hoard a bunch so they could go folks with more urgent needs.

So my goal is to figure out how to maximize the usable life of the ones I have.

Since I won't be wearing them in high-dust environments, and probably only for short stints while buying food and maybe gas, the main "risk" as i see is that potentially a bunch of nasties like virus and bacteria could start building up and a used mask could eventually become a source of infection rather than a prophylactic. The only thing I've seen regarding cleaning them for reuse involves vaporized H2O2, something I'm not really set up to do.

The only alternative I can think of is heat. That won't clear particles so the masks will eventually be unusable due to clogging, but I'd prefer if there are viruses in the filter that they be "dead" viruses versus viable. I was thinking of something simple like keeping one in my vehicle, which is always parked outside and anytime there is sun it gets hot inside if the windows are left up, probably 120F or more even on a modestly warm day which around here would be in the low 80s. The virus is supposed to be susceptible to heat, I believe, and regular thermal soaking at those temps should do at least some good.

I've also seen suggestions of using some other covering over the mask to lower the number of incoming particles that make it though to the mask. I thought about going to my local walmart and grabbing a piece cloth of some sort and cutting roughly to bandana size (or finding a bandana) and wearing it cowboy/bandit style. Actually, that alone meets the low end of the CDC guidelines. I also thought about buying and cutting up a few HEPA air filters if they could be found and trying to rig a covering with them.

Is there an ere conventional wisdom for extending the life of "disposable" respirator masks?

[Dream of Freedom]

[quote=IlliniDave post_id=211713 time=1585999554 user_id=3Is there an ere conventional wisdom for extending the life of "disposable" respirator masks?
[/quote]

Putting it in the oven at 70 c (158 f) for 30 min or steaming it fr 10 min should disinfect it. I don't know how it will effect the bands that hold it on or the fit. With homemade masks apparently vacuum cleaner bags are pretty good.

https://m.box.com/shared_item/https%3A% ... 19-PPE-1-1

[J_]

reuse mask: let it dry, hang it in the sun UV kills virus.

[Bankai]

It's interesting that the US advised to wear them on the same day the UK re-confirmed not to wear them justifying this with a lack of evidence that they actually work. I was under the impression that the standard masks only stop bigger droplets and since COVID spreads via aerosols and stays in the air for quite a while they won't be of much help?

[The_Bowme]

It's interesting that the US advised to wear them on the same day the UK re-confirmed not to wear them justifying this with a lack of evidence that they actually work. I was under the impression that the standard masks only stop bigger droplets and since COVID spreads via aerosols and stays in the air for quite a while they won't be of much help?

Here's latest from slate star codex in the subject.
https://slatestarcodex.com/2020/03/31/s ... oth-masks/

[bostonimproper]

@IlliniDave The biggest benefit of mask-wearing (at least what is guiding CDC recommendation) is the benefit to others rather than the user. If a person has COVID-19 or is asymptomatic, then the droplets of respiration are restricted by the mask and their reach is limited. Assuming everyone or a large portion thereof wears a mask, this brings transmission rates way down. So pretty much anything, including a bandana wrapped around the face, should suit this purpose. Assuming you are using the N95's for a protective purpose, to prevent illness and reduce viral load, consider going out with goggles as well since ocular transmission is apparently a thing.

To your original question, what we are doing is using cloth mask covers my husband sewed over our P100s, wash mask covers after each use, and hanging the masks themselves on the balcony for a day to let them air out and have UV do its disinfecting thing before bringing them back inside. The virus itself is only viable on surfaces for a few days and we're not planning to leave the house that often anyway. Just need be careful not to touch the outside and inside of the mask.

Relevant notes on FFR reuse and microorganism survival on filters.

[IlliniDave]

It's interesting that the US advised to wear them on the same day the UK re-confirmed not to wear them justifying this with a lack of evidence that they actually work. I was under the impression that the standard masks only stop bigger droplets and since COVID spreads via aerosols and stays in the air for quite a while they won't be of much help?

Do they really know for sure the virus's propagation methods yet? I thought what I'd heard was the droplet M.O. projected from sneezing/coughing was the leading candidate, either breathed in, or the droplets falling and infecting surfaces? But that is relatively old info and still somewhat speculative at the time.

What I remember hearing that it was much more important for infected people to wear masks than it was for not infected people (healthcare workers and first responders aside), to contain droplet spray. But it's had to know who to believe. I have only heard about the new CDC guidance second-hand, i.e., I did not watch the press briefing yesterday to hear what the medical pros gave as a reason (assuming they were asked and it wasn't just a bunch of gotcha questions, which is why I quit tuning in).

J_ and DreamofFreedom. Thanks. The masks I have have been stored in my garage for about 7 years. No climate control so it gets brutally hot in the summer. The elastic used (brand is 3M) seems to have held up pretty good. Everyday elastic bands don't last a year out there. I don't think the garage gets to 158F though. My oven is older and the first mark on the dial is 200F, but I suppose I can eyeball. I'd guess a longer soak at 120F+ might achieve the same end. I thought I'd read that at 100F the persistence of the virus decreased to minutes from hours. So if I can get the interior of the mask above 100F a few hours a day and only wear it once a week for the 20-30 minute it takes me to hustle through the grocery, I should be okay.

In the world of ironies, we're having another cooler than normal spring here. If there was ever a time I'd want to see an "all-time hottest" streak, it would be the next three months.

Work is another matter. If they begin mandating masks and don't provide them, I'll probably have to quit going in, as my micro-hoard might not last long being used all day every day.

The good news is I found a third unused mask in the garage.

[Bankai]

Yeah, it's all still speculation. The initial assumption was that it's just the big droplets from coughing/sneezing but then there are stories like this one https://www.latimes.com/world-nation/st ... r-outbreak where no one sneezed or coughed and still 45 got infected.

[IlliniDave]

@IlliniDave The biggest benefit of mask-wearing (at least what is guiding CDC recommendation) is the benefit to others rather than the user. If a person has COVID-19 or is asymptomatic, then the droplets of respiration are restricted by the mask and their reach is limited. Assuming everyone or a large portion thereof wears a mask, this brings transmission rates way down. So pretty much anything, including a bandana wrapped around the face, should suit this purpose. Assuming you are using the N95's for a protective purpose, to prevent illness and reduce viral load, consider going out with goggles as well since ocular transmission is apparently a thing.

To your original question, what we are doing is using cloth mask covers my husband sewed over our P100s, wash mask covers after each use, and hanging the masks themselves on the balcony for a day to let them air out and have UV do its disinfecting thing before bringing them back inside. The virus itself is only viable on surfaces for a few days and we're not planning to leave the house that often anyway. Just need be careful not to touch the outside and inside of the mask.

Relevant notes on FFR reuse and microorganism survival on filters.

Thanks. Honestly my biggest concern today is simply being compliant, and/or to avoid being an asymptomatic carrier. N95 is just what I have. The event they tighten up the guidance that it must be a fitted mask and make it mandatory is what I'm thinking ahead too.

This is a weird situation for me. It's probably been 30 years since I had the flu, so my immune system and habits protect me pretty well. About once every 5-10 years I get a bronchial infection which results in a productive cough, but no fever or other flu-like symptoms, and those tend to come during peak allergy season (June and September around here). But having a history of asthma, generally mild now, but was more severe when I was a kid (never hospitalization-level severe), means I'm leery of c-19. Past history suggests I might well get infected and never know it. I can't imagine I have not been exposed to the flu viruses over the last 30 years. So at present I'm not too worried about myself, just don't want to be a mechanism for spread. However when it gets more prevalent in my area I will probably shift to a more defensive posture due to Pascal's wager logic.

Unfortunately I get more ere points deducted because I don't have a machine and probably couldn't sew with it if I did. I have a little sewing kit for bush fixes but I keep that at the cabin with my "wilderness" gear (along with my bandanas). I like the idea of a washable outer cover, which the bandanna would suffice for. If nothing else I have some table napkins and microfiber cloths that are a hair too small for the bandit look tied in back, but I could probably do something with a safety pin. I also have a bunch of scarves, but the thought of using one of those through the summer relegates it to an emergency option.

[IlliniDave]

Yeah, it's all still speculation. The initial assumption was that it's just the big droplets from coughing/sneezing but then there are stories like this one https://www.latimes.com/world-nation/st ... r-outbreak where no one sneezed or coughed and still 45 got infected.

That's interesting (and worrisome). Of course you have a roomful of people expelling air above and beyond normal respiration in a choir setting, but it is less powerful expulsion than coughing or sneezing.

[Jin+Guice]

Re: Masks

I'm suspicious when there's a CDC recommendation that healthcare workers do one thing and the general population do another. I can't imagine there is harm in wearing a mask if you already have one, especially if you figure out a way to reuse it.

Louisiana has tested about 1.2% (assuming no double tests) of its population with about ~19% positive. ~3.6% of those who tested positive have died and another ~16.6% in hospitals (5.2% of the positive tests are on vents). New Orleans is at an ~25% positive test rate with ~4.26% death rate amongst positive tests. To my knowledge, no hospitals have run out of vents or beds yet.

I'm not sure this adds anything to the discussion about a large amount of asymptomatic carriers, since Louisiana hasn't been able to test enough, given the high prevalence here.

[Jason]

Fauci responded 50/50 when asked about the effectiveness of a mask, ultimately saying "it can't hurt."

Looks like Suo was ahead of the curve.

https://www.bloomberg.com/news/articles ... uarantines

[George the original one]

Covid Trends has now included the option to view USA, Australia, Canada, and China by state/province.

USA plots show that only Alaska has left the COVID-19 trajectory with Washington, Oregon, & Arkansas on the cusp of leaving. New York is bending the trajectory, but still a long ways from leaving.

https://aatishb.com/covidtrends/?region ... Washington

Now California looks like they're on the cusp of leaving the trajectory.

[George the original one]

Countries leaving the COVID-19 trajectory
Australia
Austria
China
Finland
Germany
Italy
Luxembourg
Norway
South Korea
Spain
Switzerland

https://aatishb.com/covidtrends/?locati ... ed+Kingdom

[George the original one]

Does anyone know if their state has a higher percentage of total population tested? I'd be curious to know those negative PCR rates.

Washington 1.06% tested, 8.4% of tests are positive
Oregon 0.41% tested, 5.2% of tests are positive

[jacob]

The case/1M and tests/1M stats at the country level can be found on https://www.worldometers.info/coronavirus/ (all the way to the right of the table).

[macg]

@IlliniDave, a friend of mine with CF has re-used n95 masks to some degree for years, by covering the outside. She has generally modified some form of HEPA air filter as the covering

[CS]

Apologies if someone has already posted this -

https://drive.google.com/file/d/1kVPWMn ... gN23e/view

Abstract
The COVID-19 disease is one of worst pandemicsto sweep the globe in recent times. It is noteworthy
that the disease has its greatest impact on the elderly. Herein, we investigated the potential of
childhood vaccination, specifically against measles, mumps and rubella (MMR), to identify if this
could potentially confer acquired protection over SARS-CoV-2. We identified sequence homology
between the fusion proteins of SARS-CoV-2 and measles and mumps viruses. Moreover, we also
identified a 29% amino acid sequence homology between the Macro (ADP-ribose-1’’-phosphatase)
domains of SARS-CoV-2 and rubella virus. The rubella Macro domain has surface-exposed conserved
residues and is present in the attenuated rubella virus in MMR. Hence, we hypothesize that MMR
could protect against poor outcome in COVID-19 infection. As an initial test of this hypothesis, we
identified that 1) age groups that most likely lack of MMR vaccine-induced immunity had the
poorest outcome in COVID-19, and 2) COVID-19 disease burden correlates with rubella antibody
titres, potentially induced by SARS-CoV2 homologous sequences. We therefore propose that

vaccination of ‘at risk’ age groups with an MMR vaccination merits further consideration as a time-
appropriate and safe intervention.

I had to get tested (titered) for immunity in my thirties when I'd gone back to school. I'd lost immunity
to one of the three diseases (my online records don't go back that far, so I don't know which one).
Childhood immunizations don't last that long.

That is getting to be a while back, so I'm calling my doctor next week to see to see what she thinks
about a booster. Someone said it is subcutaneous (an easy shot to give yourself) so conceivably
this could come from a mail order pharmacy and be done in the home.

[jacob]

@CS - Interesting. Most of the older crowd (depending on when vaccination was introduced in their country) would almost surely have contracted rubella directly which does confer lifelong immunity.

[Ego]

@CS, that would be incredible and would explain why kids are not susceptible.

According to my records last MR vaccination was in 1995. I got tested for immunity in 2014 when I took the EMT course. I see that CVS Clinics in the US perform the MMR vaccination for $135 and they have appointments today. Hum