Continuation The One Covid-19 Science and Medicine Thread Part 3

[mike81]

https://www.latimes.com/california/s...ined?_amp=true

"When the state says a region has reached 0%, it may actually still have some beds available. Individual counties, such as Fresno, have reported having no open ICU beds."

[marting]

Originally Posted by mike81

If lockdowns work so well, how come New York and California did so terrible with having some of the strictest rules around?

Yeah, New York did bad as did Mass. and N.J. But they also saw Covid-19 come in early when there were few tests and it was mostly in the news from China and Italy. By the time they got serious with a lockdown the cake was baked. Takes about a month from getting infected, and 3 weeks from hospitalization to die.

California, OTOH, certainly wasn't hard hit. They lucked out even though the first Covid-19 death actually occurred in California on Feb. 7. Moderate weather probably slowed the spread as did relatively early lockdowns. As a result, the deaths so far in CA are lower than most states at .05% There are only 11 states with lower cumulative deaths per capita. While it's seeing an increase, like in most places, it's continuing to improve relatively. Two weeks ago 12 states had lower per capita deaths.

Quote:

Not that most people even know what the infection fatality rate is. They assume it's much higher than it is.

I think perceptions vary a lot. The media doesn't talk about it much. Pretty much didn't talk about death rates until we started exceeding the Spring peaks. All cases, cases, cases. But it was pretty obvious that the high CFR we had in the Spring was no where near what the IFR was which was probably 10x lower. Since then CFR has dropped to 1.5 to 2% though there are signs it's climbing a bit since the percentage of positive tests has increased in the last month or so. My estimate of IFR is .6% though it's been running lower since May as new infections are mostly among younger groups. People over 65 are doing a much better job of keeping safe and it's helping the IFR. These stats over time are on my county's website. Though technically, IFR is age agnostic. That is, what percentage of the total population would die if everyone got infected?

Quote:

Some of us are also sick of the moving goal post. At first it was flatten the curve. We did that. Then it was wear a mask until we get a vaccine and get something like 60% of people vaccinated. Now that percentage keeps going up. Fact is that there are some who just do not want this to end.

I don't know anyone that doesn't want this to end.

Quote:

The reporters and politicians have become celebrities and do not want to let go of the power. After all, what will they report on once Trump is out of office and the Coronavirus is not a big deal anymore? We wouldn't want Cuomo to not be able to go on TV everyday and act like a dictator now would we?

I remember some that thought Covid-19 was being hyped just to attack Trump. But that doesn't explain what's happening in the rest of the World. But yeah, there's a lot of Covid-19 fatigue. However, rolling out the vaccine to healthcare/essential employees, and the elderly will have a disproportionate effect (reduction) on the death rate since it is so skewed towards age and infections. I also expect a significant reduction in cases too starting in Jan/Feb and declining to much lower levels by summer. Things should be relatively normal by Fall.

[marting]

Originally Posted by mike81

The CDC disagrees. You have some info that they do not?

The last estimate the CDC had was 53M total infections with an estimate of the actual as 7.7 times the reported Covid-19 cases. But that was as of the end of Sept. and was heavily skewed by the smaller number of tests done earlier. Since then the total number of cases has more than doubled! Currently at 16.3M. Fewer cases are getting missed. Might now be about 5x. It wasn't 10x then and there's no way it's 10x now or half the USA would have gotten it and we would not be seeing the ramps in cases and now deaths.

https://www.cdc.gov/coronavirus/2019...es/burden.html

[The Atheist]

Originally Posted by marting

Current USA Cases: 16.3M. 10x would be 163M. Population is 330M. That would be 49% of the USA population is/was infected. We would be seeing significant effects from herd immunity were that the case given all the NPIs in place.

It doesn't look impossible to me - the growth rate of new infections is slowing and looks very much like it will be over the hump in a week or two, as every other country with high infection rates is starting to show.

If the infection was nowhere near 50% you'd see the daily increase still increasing, not reducing. Take a look at the 7-day average and check in another fortnight.

[Lplus]

Originally Posted by Bob001

Apparently severe covid reactions are related to five specific genes. I wonder if people could be pretested for those genes so if they contract covid they could be treated aggressively earlier.

https://www.yahoo.com/news/five-key-...161436410.html

The abstract in Nature is here https://www.nature.com/articles/s41586-020-03065-y

Download the pdf to read the actual article.

[Modified]

Originally Posted by The Atheist

It doesn't look impossible to me - the growth rate of new infections is slowing and looks very much like it will be over the hump in a week or two, as every other country with high infection rates is starting to show.

If the infection was nowhere near 50% you'd see the daily increase still increasing, not reducing. Take a look at the 7-day average and check in another fortnight.

If it was 10x, 115% of people in North Dakota and over 100% in South Dakota would have had it.

Cases in those states are decreasing but they are not zero. 5x or so makes a lot more sense. Some percentage of the population are isolating effectively and that has probably increased lately, so they may be closing in on herd immunity for those who aren't isolating.

[The Atheist]

Originally Posted by Modified

If it was 10x, 115% of people in North Dakota and over 100% in South Dakota would have had it.

Cases in those states are decreasing but they are not zero. 5x or so makes a lot more sense. Some percentage of the population are isolating effectively and that has probably increased lately, so they may be closing in on herd immunity for those who aren't isolating.

With small populations, those places would easily average out if NY has had somewhat more than 10 times the known case load.

Like I said, give it a couple of weeks and we'll have a lot more clarity.

Whether 5 or 10, it's 100% certain the true numbers are a lot more than the tested figure.

[Modified]

Originally Posted by The Atheist

With small populations, those places would easily average out if NY has had somewhat more than 10 times the known case load.

Like I said, give it a couple of weeks and we'll have a lot more clarity.

Whether 5 or 10, it's 100% certain the true numbers are a lot more than the tested figure.

I highly suspect that there has been less testing per capita of the asymptomatic in the Dakotas than in New York, so if anything the multiple of unknown cases would be higher there. Even 5x may be a stretch nation wide.

[The Atheist]

Originally Posted by Modified

I highly suspect that there has been less testing per capita of the asymptomatic in the Dakotas than in New York, so if anything the multiple of unknown cases would be higher there. Even 5x may be a stretch nation wide.

I've been having a look at countries with a death rate greater than 0.1% of their populations, currently: France, Belgium, Peru, Spain, Italy, Bosnia, N Macedonia and Montenegro.

They all have dropping new infection rates. Stricter measures would account for some of the western European nations, but the Balkan states and Peru seem to have been consistently lax in their approach, so they look like seeing the effect of some degree of herd immunity.

Texas and Florida may be seeing the same thing, but you can't trust the data from those third world areas.

[rjh01]

Originally Posted by arthwollipot

Today marks Australia's first 7-day period with no community transmission since 29 February. 100% of our cases are returning overseas travellers in hotel quarantine.

It is possible to eradicate this virus.

Originally Posted by lionking

Despite Hunt saying this, I don’t think it’s true. I follow the count daily, and I don’t recall seeing a community transmission for at least 2 weeks.

Your larger point, of course, is correct.

I have been following the stats. On 29 November there had been 22,091 local cases. It still is that number. But the number of cases in NSW has gone up by one and down by two and QLD up by one. So it probably is about right.

I just want to know when most of the remaining restrictions will be removed.

[marting]

The following video on vitamin D is the best overview I've run across. It just came out 2 days ago. It's pretty consistent with what's been posted here previously but puts the key studies together.

https://youtu.be/ha2mLz-Xdpg

[EHocking]

Originally Posted by Modified

I highly suspect that there has been less testing per capita of the asymptomatic in the Dakotas than in New York, so if anything the multiple of unknown cases would be higher there. Even 5x may be a stretch nation wide.

Reading the CDC statement may well have helped you all with your numbers.

We estimated that through the end of September, 1 of every 2.5 (95% Uncertainty Interval (UI): 2.0–3.1) hospitalized infections and 1 of every 7.1 (95% UI: 5.8–9.0) non-hospitalized illnesses may have been nationally reported. Applying these multipliers to reported SARS-CoV-2 cases along with data on the prevalence of asymptomatic infection from published systematic reviews, we estimate that 2.4 million hospitalizations, 44.8 million symptomatic illnesses, and 52.9 million total infections may have occurred in the U.S. population from February 27–September 30, 2020.

My bolding .

[Modified]

Originally Posted by EHocking

Reading the CDC statement may well have helped you all with your numbers.

We estimated that through the end of September, 1 of every 2.5 (95% Uncertainty Interval (UI): 2.0–3.1) hospitalized infections and 1 of every 7.1 (95% UI: 5.8–9.0) non-hospitalized illnesses may have been nationally reported. Applying these multipliers to reported SARS-CoV-2 cases along with data on the prevalence of asymptomatic infection from published systematic reviews, we estimate that 2.4 million hospitalizations, 44.8 million symptomatic illnesses, and 52.9 million total infections may have occurred in the U.S. population from February 27–September 30, 2020.

My bolding .

So 7x at the end of September, but given the surge since then that may be off quite a bit from the current multiple.

[The Atheist]

A little more on the auto-immune aspect of Covid: https://www.theguardian.com/science/...es-study-shows

My youngest son had part of his large intestine removed due to an auto-immune disease, so I'm acutely interested in this angle.

While being very happy we live Covid-free down here.

[marting]

Assessing the age specificity of infection fatality rates for COVID-19: systematic review, meta-analysis, and public policy implications

https://link.springer.com/article/10...54-020-00698-1

The estimated age-specific IFR is very low for children and younger adults (e.g., 0.002% at age 10 and 0.01% at age 25) but increases progressively to 0.4% at age 55, 1.4% at age 65, 4.6% at age 75, and 15% at age 85.

And here's the formula (IFR in percentage).

Log10(IFR) = -3.27 + .0524*Age
Stdev of factors: .07, .0013

Excel age v IFR (%)
0 0.001
10 0.002
20 0.006
30 0.020
40 0.067
50 0.224
60 0.748
70 2.500
80 8.356
90 27.925


I found this interesting because of the heavily skewed Covid-19 infections towards younger people in this CDC report. 21% of 18-49 Y/O's infected v 17% of 50-64 Y/O's and 11% of 65+ YO's. This also tracks what I see in our county. In the first phase of the pandemic, the case age distribution was similar for older and younger groups but then, in April, shifted with younger people having a bit over 2X more likely to test positive than older people.

Implicit is that older people got the message that they are at higher risk and accorded themselves appropriately. Also, it's more easily done as they are more likely to be retired. Aside from those unfortunate ones in LTC facilities which suffered disproportionally.

https://www.cdc.gov/coronavirus/2019...es/burden.html

[jimbob]

On the "Oh but the rise in cases is driven by false positives" narrative



If that were the case, then the positivity rate for symptomatic and asymptomatic cases in England would be in tandem - data from the week 50 report for England here:

https://www.gov.uk/government/statis...llance-reports

[The Atheist]

Originally Posted by marting

Assessing the age specificity of infection fatality rates for COVID-19: systematic review, meta-analysis, and public policy implications

I have to wonder why it's taken this long for some solid data on that, because I've been checking and that's the first reliable set I've seen.

Good work!

Adding to that, the unknown extent of long-term harm and it's proof it's not a fun virus.

[marting]

Originally Posted by The Atheist

I have to wonder why it's taken this long for some solid data on that, because I've been checking and that's the first reliable set I've seen.

Yep. I've been looking for a good, age v IFR study as well. And this new one finally came out. By far the best overall IFR study I've seen.

An interesting point is that it's way more deadly than the flu at age 55 and far more at 65. OTOH, it's far less deadly for people under 30.

An interesting side effect is that the NPIs put in place has pretty much killed flu deaths which are more evenly distributed. So deaths of people under 20 are actually down from a year ago.

Interesting beast.

I also downloaded the census data broken down in 1 y age intervals. Applying the CDC age distribution of infected people, the IFR comes in at about .5% But that's to date. Presumably treatments have improved survival rates a bit since the beginning. OTOH, if everyone were being infected at the same rate the IFR of the USA population comes out to 1.1% before applying treatment improvements that I think have improved things. Good thing older people are being more cautious.

[The Atheist]

Originally Posted by marting

An interesting point is that it's way more deadly than the flu at age 55 and far more at 65. OTOH, it's far less deadly for people under 30.

Yeah, the difference is very, very stark.

I'm seriously drawn to childhood vaccinations providing protection. It's months ago I posted the data on the Salk & MMR vaccines protecting from multiple other illnesses.

Pity you can't test for it, because it'd be more than funny if we could have stopped all this by giving everyone autism instead.

Originally Posted by marting

An interesting side effect is that the NPIs put in place has pretty much killed flu deaths which are more evenly distributed. So deaths of people under 20 are actually down from a year ago.

Interesting beast.

Yep, that shows there's something screwy going on - other coronaviruses don't seem to infect kids less, the 'flu certainly isn't, and lots of childhood viruses affect only kids.

'Flu deaths in NZ were down by >99% this year, which I'm pretty sure has been mentioned elsewhere, along with every group showing fewer deaths.

[steenkh]

Originally Posted by The Atheist

'Flu deaths in NZ were down by >99% this year, which I'm pretty sure has been mentioned elsewhere, along with every group showing fewer deaths.

This is surprising, because the flu may have been collaterally damaged by your elimination of SARS-COV-2, but are you also putting COVID-19 negative flu carriers in quarantine?

By the way, I hear that here in Denmark a scabies epidemic was stopped cold in its tracks when Denmark closed down in the spring because of COVID-19.

[The Atheist]

Originally Posted by steenkh

By the way, I hear that here in Denmark a scabies epidemic was stopped cold in its tracks when Denmark closed down in the spring because of COVID-19.

Nobody has been tested for influenza, and I think the mere fact of 14 days of quarantine meant that anyone could develop and get over it in that time.

They were being checked for symptoms constantly, so they'd have hit the warning button at some stage.

[Planigale]

Originally Posted by marting

Yep. I've been looking for a good, age v IFR study as well. And this new one finally came out. By far the best overall IFR study I've seen.

An interesting point is that it's way more deadly than the flu at age 55 and far more at 65. OTOH, it's far less deadly for people under 30.

An interesting side effect is that the NPIs put in place has pretty much killed flu deaths which are more evenly distributed. So deaths of people under 20 are actually down from a year ago.

Interesting beast.

I also downloaded the census data broken down in 1 y age intervals. Applying the CDC age distribution of infected people, the IFR comes in at about .5% But that's to date. Presumably treatments have improved survival rates a bit since the beginning. OTOH, if everyone were being infected at the same rate the IFR of the USA population comes out to 1.1% before applying treatment improvements that I think have improved things. Good thing older people are being more cautious.

Prof. Spiegelhalter points out there is a linear relationship between age and mortality, mortality doubles for every seven years from childhood.
https://wintoncentre.maths.cam.ac.uk...-19-represent/

[alfaniner]

The actual rollout and vaccinations begin in the US today. So far the reporting has been on the minutiae of where the boxes of vaccine are at any given moment. I think I have to avoid any TV reporting for a day or two because I know it's going to be nothing but quick cuts to people getting their shots, and I hate that.

[wobs]

New variant in South East England:
https://www.bbc.co.uk/news/health-55308211

Quote:

A new variant of coronavirus has been found which is growing faster in some parts of England, MPs have been told.

Health Secretary Matt Hancock said at least 60 different local authorities had recorded Covid infections caused by the new variant.

He said the World Health Organization had been notified and UK scientists were doing detailed studies.

He said there was "nothing to suggest" it caused worse disease or that vaccines would no longer work.

[marting]

Paper pushing back on the notion that "herd immunity" would require only 10 to 20% of the population to have been infected. Some in the USA were speculating that was the case but the rapid rise and accumulation of new infections/deaths has killed that bit of wishful thinking.

https://icite.od.nih.gov/covid19/sea...42289.full.pdf

Quote:

The fragility of the Aguas et al. study undermines a key premise of GBD and other recent calls for “herd immunity” strategies. To their credit, the authors clearly demonstrate that population heterogeneity in susceptibility to infection can dramatically lower the herd immunity threshold . However, their model can only disentangle the impacts of heterogeneity versus interventions on COVID-19 transmission when approached with sufficient data and validated assumptions. Our rough, but arguably more plausible, re-estimates of the COVID-19 HIT corroborate strong signals in the data and compelling arguments that most of the globe remains far from herd immunity

[Rolfe]

What do they actually mean by herd immunity though? There's no possibility the virus could disappear from the population at that level of immunity. (That's what herd immunity really means, despite recent attempts to redefine it as something else nobody can quite explain. The "herd" is immune and the virus cannot persist in the population even though some individuals are not immune. You're talking north of 80% here. It's a vaccination phenonenon.)

[rjh01]

Originally Posted by Rolfe

What do they actually mean by herd immunity though? There's no possibility the virus could disappear from the population at that level of immunity. (That's what herd immunity really means, despite recent attempts to redefine it as something else nobody can quite explain. The "herd" is immune and the virus cannot persist in the population even though some individuals are not immune. You're talking north of 80% here. It's a vaccination phenonenon.)

Got to be careful here. Suppose 80% of the population get the vaccine. But the vaccine gives immunity to only 62.5% of these people. That would mean that for every two people who would have caught the virus before the vaccine, one person still would get ill. Hence the less effective the vaccine and the more infectious the virus the greater the % of people who need to be vaccinated to stop the spread.

NB: The 80% and 62.5% are numbers from one of my body cavities.

[Rolfe]

That's why you need to vaccinate a higher percentage of the population than the actual herd immunity threshhold.

People who don't mount an effective immune response despite being vaccinated
People who can't be vaccinated as they're immunosuppressed
People with medical contraindications to vaccination such as a history of allergy
People too young to vaccinate.

Once you've allowed for these legitimately non-immune individuals there isn't much space for antivaxer freeloaders.

[marting]

The term "Herd Immunity" as used in most studies I've seen is the percentage of the population that is immune by vaccination or prior infection/recovery such that the R is 1 with no NPIs. For an R0 of 2.5, this is 60% assuming homogeneous transmission. Typically one tries for a higher percentage so that infections exponentially decay.

That said there's a lot of unknowns.

1. how much does R0 with no NPIs vary seasonally?
2. what is the distribution over time in falloff of immunity? Not in the sense of not getting sick but of not being a source of transmission on re-infection sick or not.

[Rolfe]

Eventually, that gets you there. This thing isn't transmitted homogeneously though. I'm not sure if that's an advantage or not. Japan seems to have done pretty well by targeting superspreader events.

[Dr.Sid]

Japan is not peachy .. https://www.worldometers.info/coronavirus/country/japan
It's getting worse. At the moment their numbers are still very low, but the trend is clear.
Sure they have culture of obeying the law and considering others. But they also have tons of old people and great population density.

[marting]

Originally Posted by Rolfe

Eventually, that gets you there. This thing isn't transmitted homogeneously though. I'm not sure if that's an advantage or not. Japan seems to have done pretty well by targeting superspreader events.

Yep. It clearly isn't transmitted homogeneously. Published models of heterogeneity indicate lower herd immunity thresholds. So something isn't lining up.

Interesting that S. Korea and Japan are also showing record cases increasing rapidly after pretty much having things under control. S. Korea especially with intense track and trace and Japan has virtually 100% mask compliance.

I'm thinking this bugger's transmission dynamics may vary with temp. Could well be that fomite transmission becomes a larger factor in colder weather. It is known that SARS-CoV-2 remains viable far longer at cooler temps. Fomite transmission is much harder to trace and track than droplet/aerosol for obvious reasons.

Also, if the heterogeneous models are correct, the R0 is likely higher than 2.5.

I recall a unique situation with a summer camp (no NPIs at the camp) the CDC published where the attack rate over a period of a few weeks from one infected high school student was 91%. And this was in a population where 15% were already immune from prior infection and recovery.

An R0 of 2.5 with no NPIs seems too low.

In Calif. where I am, everyone I've seen are masked but infections are rocketing.

[rjh01]

One new case in Western Australia, but this was almost a foregone conclusion
https://www.abc.net.au/news/2020-12-...arwin/12983038

Quote:

the new infection is an 18-year-old who entered hotel quarantine to act as a guardian for his younger brother, who had returned from overseas.

The younger brother had earlier tested positive to coronavirus.

Both remain in hotel quarantine.

[Bubba]

Quote:

PEP with HCQ has the potential for the prevention of COVID-19 in at-risk individuals. Until definitive therapy is available, continuing PEP with HCQ may be considered in suitable at-risk individuals. Further randomised clinical trials with larger samples are required for better evaluation of HCQ as PEP for COVID-19 prevention.

Quote:

International Journal of Antimicrobial Agents

Post-exposure prophylaxis with hydroxychloroquine for the prevention of COVID-19, a myth or a reality? The PEP-CQ Study

https://www.sciencedirect.com/scienc...24857920304350

[Bubba]

Quote:

Conclusions HCQ-associated cardiotoxicity in SARS-CoV-2 patients is uncommon but requires ECG monitoring, particularly in those aged >60 years and/or taking other QT-prolonging drugs.

Quote:

International Journal of Antimicrobial Agents

Frequency of Long QT in Patients with SARS-CoV-2 Infection Treated with Hydroxychloroquine: A Meta-analysis

https://www.sciencedirect.com/scienc...24857920304234

[Roger Ramjets]

Originally Posted by marting

Interesting that S. Korea and Japan are also showing record cases increasing rapidly after pretty much having things under control. S. Korea especially with intense track and trace and Japan has virtually 100% mask compliance.

Masks alone aren't enough.

Japan are in trouble because they didn't finish the job. The only strategy that really works is elimination.

Quote:

I'm thinking this bugger's transmission dynamics may vary with temp. Could well be that fomite transmission becomes a larger factor in colder weather. It is known that SARS-CoV-2 remains viable far longer at cooler temps. Fomite transmission is much harder to trace and track than droplet/aerosol for obvious reasons.

Fomite transmission has been shown to occur time and time again, yet we are told that it is insignificant. Clearly that is not the case.

[Skeptic Ginger]

Originally Posted by Roger Ramjets

Masks alone aren't enough.

Japan are in trouble because they didn't finish the job. The only strategy that really works is elimination.

Fomite transmission has been shown to occur time and time again, yet we are told that it is insignificant. Clearly that is not the case.

Dismissed or not, show me the study. Curious minds want to know how important wiping things down with those chlorox wipes are.

[EHocking]

Originally Posted by Skeptic Ginger

Dismissed or not, show me the study. Curious minds want to know how important wiping things down with those chlorox wipes are.

I flew interstate this week and the airline supplied a mask and 3 surface wipes.
So (the law of) I used one of the wipes to wipe down the arm rests, pull out table, sides of the seat and even the belt buckle.

It came back black. I think I’ll be wiping down future airline seats I occupy even when COVID precautions become less necessary.

[Roger Ramjets]

More Albertans have died from COVID in 10 months than in past 10 years of flu

Quote:

CALGARY -- A review of Alberta Health data on influenza deaths show more people have died of COVID-19 in 2020 that died of flu since the 2009-10 flu season.

A review of the reported data showed no more than 562 people died from the flu, compared to the 719 deaths attributed to COVID-19 since March.

Protestors angered by public health officials and government responses to the novel coronavirus have commonly claimed tests are falsely identifying seasonal flu as COVID-19.

But an immunologist with University of Calgary’s Cumming School of Medicine says that’s impossible.

“There is essentially no way to confuse an influenza virus — which looks completely different genetically and structurely from coronavirus,” says Craig Jenne

But numbers don't really matter to the denialists. They just presumed that Covid-19 deaths wouldn't be much higher than flu deaths, and used that presumption to argue against lockdowns etc. Well guess what BSers, you were WRONG!

And another thing...

Quote:

As of December 10 there were no reported cases of lab-verified influenza in the province so far this season.

Yet another example of Covid-19 measures having an unintended positive effect.

[rjh01]

Originally Posted by Skeptic Ginger

Dismissed or not, show me the study. Curious minds want to know how important wiping things down with those chlorox wipes are.

The answer is that no one knows for sure. Most people who may have got the virus from fomite transmission could also have got it from air transmission. And seeing that your post is asking for links here are mine.

Quote:

Despite consistent evidence as to SARS-CoV-2 contamination of surfaces and the survival of the virus on certain surfaces, there are no specific reports which have directly demonstrated fomite transmission. People who come into contact with potentially infectious surfaces often also have close contact with the infectious person, making the distinction between respiratory droplet and fomite transmission difficult to discern. However, fomite transmission is considered a likely mode of transmission for SARS-CoV-2, given consistent findings about environmental contamination in the vicinity of infected cases and the fact that other coronaviruses and respiratory viruses can transmit this way.

https://www.who.int/news-room/commen...t%20this%20way.

Quote:

The longest survival (6 days) of severe acute respiratory syndrome coronavirus (SARS-CoV) on surfaces was done by placing a very large initial virus titre sample (107 infectious virus particles) on the surface being tested.1 Another study that claimed survival of 4 days used a similarly large sample (106 infectious virus particles) on the surface. <snip> None of these studies present scenarios akin to real-life situations. Although I did not find measurements of coronavirus quantities in aerosol droplets from patients, the amount of influenza virus RNA in aerosols has been measured, with a concentration equivalent to 10–100 viral particles in a droplet, with even fewer infectious influenza virus particles capable of growth in a plaque assay.5

https://www.thelancet.com/journals/l...561-2/fulltext

So much effort has been put into cleaning surfaces, yet all of this may be a waste of time.