Coronavirus

[dfwatt]

https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2769235

In a nutshell, ASYMPTOMATIC and SYMPTOMATIC patients in a Korean hospital that all were SARS-Cov2 had similar viral loads as measured by RT-PCR (quantitative testing, not the faster qualitative tests used for initial diagnosis).

What's really interesting in all that is that means of course that ribosomes are getting hijacked at roughly the same rate at least initially or at least for some kind of in both symptomatic and asymptomatic folks but cytokine levels must be much lower in the asymptomatic group because of course it's cytokines that make us feel ill not the pathogen. I suspect it also means that there is a much more effective and immediate adaptive immune response in the asymptomatic folks and much less revved up innate immunity. Of course cross-reactive T cells in the asymptomatic folks would explain this nicely.

I think we're actually making progress in understanding this disease!

 

[Causalien]

So, here to consult the researchers here.

Is COVID19 proven to be airborne? If so, what is the current definition of airborne, there seems to be a lot of confusion among normal people.

 

[TEG]

So, here to consult the researchers here.
Is COVID19 proven to be airborne? If so, what is the current definition of airborne, there seems to be a lot of confusion among normal people.

Not exactly definitive, but did you see this article? :
Mounting evidence suggests coronavirus is airborne — but health advice has not caught up

 

[Causalien]

Not exactly definitive, but did you see this article? :
Mounting evidence suggests coronavirus is airborne — but health advice has not caught up

Ya I did. The ambiguity is what made me ask this question and journalist uses word play while science is pretty specific about wording. Is aerosol airborne? It seems like the medical field has pretty narrow definition of everything and I am not a M.D.

 

[TEG]

Some more articles about COVID as aerosol:
Airborne COVID-19 transmission: What you need to know - UCHealth Today
https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa939/5867798
Aerosol Transmission of COVID-19 - CEBM
Identifying airborne transmission as the dominant route for the spread of COVID-19
Transmission of COVID-19 virus by droplets and aerosols: A critical review on the unresolved dichotomy
W.H.O. to Review Evidence of Airborne Transmission of Coronavirus
Transmission of SARS-CoV-2: implications for infection prevention precautions

Airborne transmission
Airborne transmission is defined as the spread of an infectious agent caused by the dissemination of droplet nuclei (aerosols) that remain infectious when suspended in air over long distances and time.(11) Airborne transmission of SARS-CoV-2 can occur during medical procedures that generate aerosols (“aerosol generating procedures”).(12) WHO, together with the scientific community, has been actively discussing and evaluating whether SARS-CoV-2 may also spread through aerosols in the absence of aerosol generating procedures, particularly in indoor settings with poor ventilation...

 

[AlanSubie4Life]

The actual R (not accounting for susceptibility, so not effective R - might be misstating the terminology here as it depends on the framework) still probably needs to remain below 1.3 or so to keep a lid on things in NYC. Assuming 25% not susceptible.

Excellent thread here explaining this. Good to go through using correct terminology, but basically agrees with example above. I would not put too much stock in his estimate that 20% of Florida is infected - not the point of his thread, and personally l think the actual incidence is lower than that.

(Aside: Probably overestimates of the number of infections is the most likely explanation for why IFR estimates have dropped so much.)

https://twitter.com/trvrb/status/1291860659118804992?s=21

Perhaps this just means that you've transitioned from obsessing about battery degradation to obsessing about societal/cultural/political degradation? Unfortunately, it makes battery degradation look like a walk in the park. Perhaps we should go back to the first obsession?

Had not thought about it that way! Good point.

 

[AlanSubie4Life]

Some more articles about COVID as aerosol:
Airborne COVID-19 transmission: What you need to know - UCHealth Today
https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa939/5867798
Aerosol Transmission of COVID-19 - CEBM
Identifying airborne transmission as the dominant route for the spread of COVID-19
Transmission of COVID-19 virus by droplets and aerosols: A critical review on the unresolved dichotomy
W.H.O. to Review Evidence of Airborne Transmission of Coronavirus
Transmission of SARS-CoV-2: implications for infection prevention precautions

From what I’ve read it’s a marginally aerosol driven virus. Face shields, eye protection, and avoid the indoors (these measures would not be sufficient for a truly airborne virus). And don’t go inside buildings where people are unmasked. It’s not like the measles, thankfully.

A lot of the debate seems to arise from the technical definition of airborne. I don’t fully understand the distinction, nor do I understand what enables measles to be effectively transmitted through aerosols, and how those features differ with coronavirus

 

[AlanSubie4Life]

Aside: Probably overestimates of the number of infections is the most likely explanation for why IFR estimates have dropped so much.

Should clarify: as I have said before, IFR should drop a lot due to age of infection changes. However, it has (apparently) dropped even more than that. There are some theories out there (and they are just hypotheses, still not proof) that the infection to case ratio *for a given positivity* is lower now than it was in April.

 

[cwerdna]

'We cannot stop people': 250,000 are expected at a South Dakota motorcycle rally
400,000 bikers usually descend on this South Dakota town for their annual rally. And it's still happening – despite COVID-19.
Sturgis Motorcycle Rally Expected to Attract More Than 250,000 Bikers as South Dakota Sees Uptick in Coronavirus Cases
LIVE VIDEO: Bikers arrive in Sturgis, South Dakota ahead of motorcycle rally

Seems like idiot spray is in order for these people.

Hope this isn't a repost:
https://twitter.com/RexChapman/status/1291182050049953792?s=20 (with video from Aug 5)

This anti-masker in Ohio refuses to leave the DMV despite having no reason for going inside.

Bless all of the people in this building for attempting to reason with this unreasonable woman. Wear a mask.

Don’t be a bad teammate...

 

[bkp_duke]

So, here to consult the researchers here.

Is COVID19 proven to be airborne? If so, what is the current definition of airborne, there seems to be a lot of confusion among normal people.

"Airborne" is not really a binary thing in biology. It's a spectrum.

Traditionally, when we think airborne, we think of things that can just linger in the air for hours to days without gravity really affecting them. The next step down in that spectrum would be something we refer to as "droplet". Droplet basically means that (like when you sneeze) things spray out in a mist. The finer the mist, the longer they linger in the air before landing on a surface.

Research to date, as others here have pointed out, is that SARS-CoV-2 is at least pretty far along the droplet spectrum, enough so that many scientists would consider it sufficient to call "airborne".


Put it another way, if the guy 15 ft away from you coughs or sneezes, I would not wait around to see.

 

[bkp_duke]

'We cannot stop people': 250,000 are expected at a South Dakota motorcycle rally
400,000 bikers usually descend on this South Dakota town for their annual rally. And it's still happening – despite COVID-19.
Sturgis Motorcycle Rally Expected to Attract More Than 250,000 Bikers as South Dakota Sees Uptick in Coronavirus Cases
LIVE VIDEO: Bikers arrive in Sturgis, South Dakota ahead of motorcycle rally

Seems like idiot spray is in order for these people.

Hope this isn't a repost:
https://twitter.com/RexChapman/status/1291182050049953792?s=20 (with video from Aug 5)

At that size a gathering, @dfwatt should be ordering idiot spray to be dropped from planes, just like they do to put out wildfires.

 

[NikolaACDC]

People working on technical solutions
Scientists Weigh the Benefits of Air Purifiers in Fighting COVID-19 - DER SPIEGEL - International

"In recent weeks, Kähler, who heads the Institute of Fluid Mechanics and Aerodynamics at the university, has been testing a mobile room air filter. The device has two wheels and is as big as a refrigerator. It isn’t completely silent in normal operation, but it's quiet enough. And it is capable of filtering out up to 99.995 percent of even tiny aerosol particles with a diameter of 0.0003 millimeters. The physicist believes these devices could be the solution for the safe operation of restaurants, shops, offices and schools, especially in winter when ventilation becomes even more difficult.

The filtration device halved the concentration of the aerosols in question after only six minutes of operation in Kähler’s 80-square-meter (860 square foot) test room."
....
"David Brenner, a biophysicist at New York’s Columbia University, is also hoping to apply the principle to humans using a special type of UV light that is apparently harmless to large organisms. The far-UVC light, with a wavelength of 222 nanometers, can’t even penetrate the top layer of human skin, but it kills off viruses and bacteria within minutes."

------------------

Yep, while my wife forbids me to mention that word, winter will make things worse again when doors and windows stay closed and people stay mostly indoors.

 

[AlanSubie4Life]

'We cannot stop people': 250,000 are expected at a South Dakota motorcycle rally
400,000 bikers usually descend on this South Dakota town for their annual rally. And it's still happening – despite COVID-19.
Sturgis Motorcycle Rally Expected to Attract More Than 250,000 Bikers as South Dakota Sees Uptick in Coronavirus Cases
LIVE VIDEO: Bikers arrive in Sturgis, South Dakota ahead of motorcycle rally

Seems like idiot spray is in order for these people.

Hope this isn't a repost:
https://twitter.com/RexChapman/status/1291182050049953792?s=20 (with video from Aug 5)

Is it morning again in America? Or will we be mourning again in America? It's hard to know.

Here's a pleasant, freedom-loving crowd, standing up for their rights, with infectious enthusiasm, in Tempe, AZ.

https://twitter.com/ScottPresler/status/1291547690644381701?s=20

I see six facemasks in use. When combined with the miraculous T-cells, and the 5-10% of this particular AZ demographic that probably has already been infected, I think that means they may have herd immunity. I sure hope so! If not, I guess we'll be there soon!

 

[jerry33]

People working on technical solutions
Scientists Weigh the Benefits of Air Purifiers in Fighting COVID-19 - DER SPIEGEL - International

"In recent weeks, Kähler, who heads the Institute of Fluid Mechanics and Aerodynamics at the university, has been testing a mobile room air filter. The device has two wheels and is as big as a refrigerator. It isn’t completely silent in normal operation, but it's quiet enough. And it is capable of filtering out up to 99.995 percent of even tiny aerosol particles with a diameter of 0.0003 millimeters. The physicist believes these devices could be the solution for the safe operation of restaurants, shops, offices and schools, especially in winter when ventilation becomes even more difficult.

The filtration device halved the concentration of the aerosols in question after only six minutes of operation in Kähler’s 80-square-meter (860 square foot) test room."
....
"David Brenner, a biophysicist at New York’s Columbia University, is also hoping to apply the principle to humans using a special type of UV light that is apparently harmless to large organisms. The far-UVC light, with a wavelength of 222 nanometers, can’t even penetrate the top layer of human skin, but it kills off viruses and bacteria within minutes."

This could make the area as safe as when it first opened in the morning, so there still won't be really good protection if masks and distances are not used in addition. (Restaurants are going to be a problem until there are wall to ceiling cubicles for each dining party with filtered air and decontamination between each party.) There is another big issue: how to ensure that enough air filters were used to clear the area. A big problem with air filters is that they are rated for a certain volume room and if you don't use enough of them, they will be less effective. Most business owners will not put in enough as I assume they will be something like $10K each with $2K for replacement filters. (The medical grade IQAir filter I have costs a few hundred to replace the filter set and it only does 1250 cu ft. If you replace when the light says, thats every couple of months.)

 

[TheTalkingMule]

So......it's August. We're sitting at an absurd 161k deaths and have 5M confirmed "cases". Where do we think our true mortality lies as of today?

10x the confirmed cases gives us 161k/50M or .322%
20x the confirmed cases gives us 161k/100M or .161%

Certainly the reality of things lies somewhere in the middle? If we include all exposures/infections, I'd be leaning more towards 100M, but that's just me. Having monitored behavior in Philadelphia and it's surrounding suburbs for the duration, I see no possibility we're below 50M Americans exposed or infected.

We needed to test/trace/isolate, pre-isolate those highly at risk in hotels procured by the CDC, work from home wherever feasible, and wear mask outside the home. Lets go ahead and write that down for next time.

 

[AlanSubie4Life]

So......it's August. We're sitting at an absurd 161k deaths and have 5M confirmed "cases". Where do we think our true mortality lies as of today?

10x the confirmed cases gives us 161k/50M or .322%
20x the confirmed cases gives us 161k/100M or .161%

Certainly the reality of things lies somewhere in the middle? If we include all exposures/infections, I'd be leaning more towards 100M, but that's just me. Having monitored behavior in Philadelphia and it's surrounding suburbs for the duration, I see no possibility we're below 50M Americans exposed or infected.

It's nearly certainly less than 50M. Covid-19 Projections says 42M (30-55M), but I happen to think they're probably slightly on the high side there. I'd guess about 35-40M so far.

Keep in mind you can't calculate the IFR the way you're doing it, because not all deaths have been accounted for with the 40M infections, and the trends have been towards older populations over the last couple weeks. It's probably more accurate to use ~190k deaths for the numerator (a month of deaths).

So that would give about 0.5%. Seems about right.

We needed to test/trace/isolate, pre-isolate those highly at risk in hotels procured by the CDC, work from home wherever feasible, and wear mask outside the home. Lets go ahead and write that down for next time.

I think we need to write that down for this time! While the 10+% of the population with immunity will certainly slow down future spread (see the Bedford thread), remember that we have not been through a winter nationwide with this virus yet (by the time this started much of the southern states were basically done with their winter). That's going to be worse than AC, even in the South. Being inside with windows closed is going to drive up the reproduction number, and 10-20% immune is simply not going to be enough to control this without all of the measures you propose. Especially if we proceed with opening schools without very careful attention (and funding) to control the spread.

 

[TheTalkingMule]

This virus is spreads a lot more easily than Swine Flu.
By this point Swine Flu's 2009 outbreak had spread to somewhere between 11% and 21% of humans on the planet, and that wasn't novel.
We're going to supermarkets, random people are working in nursing homes, and bars have been reopened.
Seems unlikely to me that only 12.1% of the US population has been exposed/infected.
I guess we can wait until all the numbers are in.

 

[TheTalkingMule]

I think we need to write that down for this time!

Lol....weird I didn't even really think of how bizarre that sentence was. Just have given up hope anything rational will be done by any parties this time around. We're too emotionally compromised at this point.

 

[AlanSubie4Life]

By this point Swine Flu's 2009 outbreak had spread to somewhere between 11% and 21% of humans on the planet, and that wasn't novel.

Yeah, but we didn't try to slow the spread. My understanding is there was relatively little immunity to that flu (that was one of the concerns, in addition to the apparently high initial mortality in children - which fortunately did not confirm at the level originally anticipated). But even if susceptibility and inherent reproduction rate was lower for that flu, there was no masking intervention, cessation of mass gathering, etc. That makes a huge difference!!!

Seems unlikely to me that only 12.1% of the US population has been exposed/infected.
I guess we can wait until all the numbers are in.

Yup. We'll see. There's quite a bit of uncertainty on this number. I think it's possible for it to be over 50M, but I don't expect it to be (at this point). We'll be there soon though. Give it another month or two. School should help.

 

[bkp_duke]

This virus is spreads a lot more easily than Swine Flu.
By this point Swine Flu's 2009 outbreak had spread to somewhere between 11% and 21% of humans on the planet, and that wasn't novel.
We're going to supermarkets, random people are working in nursing homes, and bars have been reopened.
Seems unlikely to me that only 12.1% of the US population has been exposed/infected.
I guess we can wait until all the numbers are in.

Your 10X ratio would assume there are about 10X more asymptomatic cases than symptomatic cases.

I just haven't seen anything that supports a conclusion like this.