Genuine points of uncertainty

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shpalman
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Re: Genuine points of uncertainty

Post by shpalman » Sat Jul 17, 2021 1:02 pm

Oh and here's the current graph with the latest data on it. I haven't changed my estimates.
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Re: Genuine points of uncertainty

Post by jimbob » Sat Jul 17, 2021 4:47 pm

shpalman wrote:
Sat Jul 17, 2021 12:58 pm
shpalman wrote:
Tue Jul 13, 2021 6:31 pm
lpm wrote:
Tue Jul 13, 2021 1:56 pm
It's a bit of a mystery why hospitalisation numbers are tracking below all the models' forecasts. The gearing can't be too unexpected, the age profile of new cases can't be too unexpected.

But it's going to get a lot worse over the next month.
The lag between cases and deaths actually seems to be about three weeks, with a 0.3% CFR, whereas the lag between cases and hospital admissions per day is about two weeks, with about 5% of cases ending up in hospital.

I figured this out by basically shifting the curves around on the semilog plot until they seem to match the recent minimum and then increase; the axes make direct sense only for the cases per day curve.

Image

(It's a three week lag for numbers in hospital and in ventilator beds but that's a different kind of metric, a "currently in this state" rather than "number arriving in this state today", so has a less obvious significance. The factors are 40% and 6%, respectively, whatever that means.)
Here's a similar thing done for the second wave last autumn (day 150 was the 19th of July last year):

uk-phases-2ndwave-all.png

I haven't changed the lags; the CFR was 2% (three week lag) and the admissions per day ended up being 12% of the cases per day (two week lag). I've tried to match the upward curve rather than the peak, which may have been influenced by hospital and/or testing capacity saturating, since you're currently on an upward curve and nowhere near the peak in your current wave (which is only going to accelerate since your plan is to remove rather than reintroduce restrictions). (The even less meaningful factors for numbers in hospital and in ventilator beds are 80% and 10% in this graph).

So with your impressive vaccine rollout you've managed to reduce hospital admissions by maybe a bit more than factor of 2. Regarding the saturation of hospital capacity, since the case rate has doubled in the past 15 days then well done you're currently two weeks behind yourselves in the previous wave.

You've also reduced your death rate by not quite an order of magnitude, which buys you about a month extra before oh sh.t it turns out vaccines don't break the link between cases and deaths they just reduce the CFR.

The difference between CFR and hospitalization rate is probably because younger people are ending up in hospital this time. So fewer of them die but they may occupy the bed for longer while they're in there (and be left with long covid).
Yup that's pretty much what I concluded from the phase plots
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Re: Genuine points of uncertainty

Post by Herainestold » Sat Jul 17, 2021 5:47 pm

Don't have a heart attack or a stroke or be diagnosed with cancer there isn't going to be a bed until..well, who knows, maybe some time in 2022.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by jdc » Sat Jul 17, 2021 6:40 pm

Herainestold wrote:
Sat Jul 17, 2021 5:47 pm
Don't have a heart attack or a stroke or be diagnosed with cancer there isn't going to be a bed until..well, who knows, maybe some time in 2022.
That reminds me. Someone was tweeting about length of stay in ICU earlier: https://twitter.com/caz_sampson/status/ ... 0882412550
48553 cases today. 100 more patients in ICU with covid19 than 5days ago. No one talking about covid length of stay so I will.

Median ICU stay:-

Heart/major cancer surgery 1-2d
Covid (not ventilated) 5d
Covid (ventilated) 20d
Covid (kidney support) 32d

Do the maths

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Re: Genuine points of uncertainty

Post by shpalman » Sun Jul 18, 2021 1:16 pm

It occurred to me to try the same thing for Italy. In the second wave we had a CFR of 2% once we got to the higher numbers. Italy only has admissions to ICU data, and it only has it starting after the wave peaked, but it's something like 1% of cases (I didn't put a 7-day lag in).

The factors for not-ICU hospital occupancy and ICU occupancy are 100% and 10%, respectively, but those aren't really meaningful (7-day lag again).
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Re: Genuine points of uncertainty

Post by Brightonian » Sat Jul 24, 2021 2:30 pm

Not sure if this belongs to this thread now, but there was some uncertainty in the past.*

Suggestion that the WHO deliberately concealed the dominant effect of aerosolised particles: https://bylinetimes.com/2021/07/23/worl ... nsmission/

* I take it that there is no longer any real uncertainty - I'm right on that, am I? (As I've virtually ceased sanitising stuff, and avoid others' enclosed premises where possible.)

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Re: Genuine points of uncertainty

Post by Herainestold » Sat Jul 24, 2021 7:04 pm

Brightonian wrote:
Sat Jul 24, 2021 2:30 pm
Not sure if this belongs to this thread now, but there was some uncertainty in the past.*

Suggestion that the WHO deliberately concealed the dominant effect of aerosolised particles: https://bylinetimes.com/2021/07/23/worl ... nsmission/

* I take it that there is no longer any real uncertainty - I'm right on that, am I? (As I've virtually ceased sanitising stuff, and avoid others' enclosed premises where possible.)
Interesting that China figured it out fairly quickly but the WHO ignored it.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by Millennie Al » Sun Jul 25, 2021 1:54 am

Herainestold wrote:
Sat Jul 24, 2021 7:04 pm
Interesting that China figured it out fairly quickly but the WHO ignored it.
That illustrates the difference between being science-led and scientist-led. To be science-led you need to check the science yourself - not rely on authorities. For some reason, China currently does genuinely look at the science.

I note also with interest, in https://bylinetimes.com/2021/01/13/redu ... -of-covid/ which I found by reading the above cited article:
Deputy Chief Medical Officer Professor Jonathan Van-Tam co-authored a 2013 paper which advocated the use of FFP3 masks in a review of the H1N1 pandemic. While “surgical face masks provide a barrier to splashes and droplets impacting on the wearer’s nose, mouth and respiratory tract”, the paper said, “they do not provide protection against airborne (aerosol) particles and are not classed as Respiratory Protective Equipment”. The paper went on to say that “whilst some surgical masks claim to have particulate filtration properties, they do not have the filtering efficiencies required for adequate respiratory protection”.
so we shold have dropped the "Hands. Face. Space" much earlier. But our governement is pretty clue-resisitant.
Covid-19 - Don't catch it: don't spread it.

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Re: Genuine points of uncertainty

Post by Herainestold » Sun Jul 25, 2021 5:40 pm

Millennie Al wrote:
Sun Jul 25, 2021 1:54 am
Herainestold wrote:
Sat Jul 24, 2021 7:04 pm
Interesting that China figured it out fairly quickly but the WHO ignored it.
That illustrates the difference between being science-led and scientist-led. To be science-led you need to check the science yourself - not rely on authorities. For some reason, China currently does genuinely look at the science.

I note also with interest, in https://bylinetimes.com/2021/01/13/redu ... -of-covid/ which I found by reading the above cited article:
Deputy Chief Medical Officer Professor Jonathan Van-Tam co-authored a 2013 paper which advocated the use of FFP3 masks in a review of the H1N1 pandemic. While “surgical face masks provide a barrier to splashes and droplets impacting on the wearer’s nose, mouth and respiratory tract”, the paper said, “they do not provide protection against airborne (aerosol) particles and are not classed as Respiratory Protective Equipment”. The paper went on to say that “whilst some surgical masks claim to have particulate filtration properties, they do not have the filtering efficiencies required for adequate respiratory protection”.
so we shold have dropped the "Hands. Face. Space" much earlier. But our governement is pretty clue-resisitant.
I thought the main drawback of medical procedure masks is they don't seal well against the face. That is why double masking works against Delta, the extra layer seals the medical mask against your skin. Not 100% but much better than either mask alone. I expect that a FFP3 msk would be even better.
I wonder if Delta is even more airborne than previous strains? That would explain the greater transmissibility and it suggests that outdoor spread would be much more prevalent.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by shpalman » Sun Jul 25, 2021 5:53 pm

Herainestold wrote:
Sun Jul 25, 2021 5:40 pm
Millennie Al wrote:
Sun Jul 25, 2021 1:54 am
Herainestold wrote:
Sat Jul 24, 2021 7:04 pm
Interesting that China figured it out fairly quickly but the WHO ignored it.
That illustrates the difference between being science-led and scientist-led. To be science-led you need to check the science yourself - not rely on authorities. For some reason, China currently does genuinely look at the science.

I note also with interest, in https://bylinetimes.com/2021/01/13/redu ... -of-covid/ which I found by reading the above cited article:
Deputy Chief Medical Officer Professor Jonathan Van-Tam co-authored a 2013 paper which advocated the use of FFP3 masks in a review of the H1N1 pandemic. While “surgical face masks provide a barrier to splashes and droplets impacting on the wearer’s nose, mouth and respiratory tract”, the paper said, “they do not provide protection against airborne (aerosol) particles and are not classed as Respiratory Protective Equipment”. The paper went on to say that “whilst some surgical masks claim to have particulate filtration properties, they do not have the filtering efficiencies required for adequate respiratory protection”.
so we shold have dropped the "Hands. Face. Space" much earlier. But our governement is pretty clue-resisitant.
I thought the main drawback of medical procedure masks is they don't seal well against the face. That is why double masking works against Delta, the extra layer seals the medical mask against your skin. Not 100% but much better than either mask alone. I expect that a FFP3 msk would be even better.
I wonder if Delta is even more airborne than previous strains? That would explain the greater transmissibility and it suggests that outdoor spread would be much more prevalent.
“Fleeting contact”
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Re: Genuine points of uncertainty

Post by Herainestold » Sun Jul 25, 2021 6:26 pm

“At the start of this pandemic, I spoke about 15 minutes of close contact being a concern. Now it looks like it’s five to 10 seconds that’s a concern. The risk is so much higher now than it was only a year ago.”
Delta changes everything.

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Re: Genuine points of uncertainty

Post by Brightonian » Sun Jul 25, 2021 6:50 pm

shpalman wrote:
Sun Jul 25, 2021 5:53 pm
Herainestold wrote:
Sun Jul 25, 2021 5:40 pm
Millennie Al wrote:
Sun Jul 25, 2021 1:54 am


That illustrates the difference between being science-led and scientist-led. To be science-led you need to check the science yourself - not rely on authorities. For some reason, China currently does genuinely look at the science.

I note also with interest, in https://bylinetimes.com/2021/01/13/redu ... -of-covid/ which I found by reading the above cited article:


so we shold have dropped the "Hands. Face. Space" much earlier. But our governement is pretty clue-resisitant.
I thought the main drawback of medical procedure masks is they don't seal well against the face. That is why double masking works against Delta, the extra layer seals the medical mask against your skin. Not 100% but much better than either mask alone. I expect that a FFP3 msk would be even better.
I wonder if Delta is even more airborne than previous strains? That would explain the greater transmissibility and it suggests that outdoor spread would be much more prevalent.
“Fleeting contact”
I keep forgetting that case, and then suddenly remember it when I smell someone's cigarette smoke or perfume or their meal and I have a minor freakout.

Right now I'm outside a café-bar, having a leisurely beer, and earlier was having a pleasant chat with a random person at the next table. And then I caught a whiff of something or other, presumably him, and suddenly I thought "I'm doomed, I'll get Covid, probably Long Covid as well", wishing he would go away. He did go away, maybe he picked up on my sudden unease.

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Re: Genuine points of uncertainty

Post by Herainestold » Sun Jul 25, 2021 7:16 pm

Brightonian wrote:
Sun Jul 25, 2021 6:50 pm
shpalman wrote:
Sun Jul 25, 2021 5:53 pm
Herainestold wrote:
Sun Jul 25, 2021 5:40 pm


I thought the main drawback of medical procedure masks is they don't seal well against the face. That is why double masking works against Delta, the extra layer seals the medical mask against your skin. Not 100% but much better than either mask alone. I expect that a FFP3 msk would be even better.
I wonder if Delta is even more airborne than previous strains? That would explain the greater transmissibility and it suggests that outdoor spread would be much more prevalent.
“Fleeting contact”
I keep forgetting that case, and then suddenly remember it when I smell someone's cigarette smoke or perfume or their meal and I have a minor freakout.

Right now I'm outside a café-bar, having a leisurely beer, and earlier was having a pleasant chat with a random person at the next table. And then I caught a whiff of something or other, presumably him, and suddenly I thought "I'm doomed, I'll get Covid, probably Long Covid as well", wishing he would go away. He did go away, maybe he picked up on my sudden unease.
That is why I won't go to even an out door cafe. If you can smell somebody's cologne or cigarette smoke, that could be covid.
Imagine how much worse it is indoors. Although if you have to be indoors for a brief period of time and you are double masked you might be okay.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by Trinucleus » Sun Jul 25, 2021 7:52 pm

Herainestold wrote:
Sun Jul 25, 2021 6:26 pm
“At the start of this pandemic, I spoke about 15 minutes of close contact being a concern. Now it looks like it’s five to 10 seconds that’s a concern. The risk is so much higher now than it was only a year ago.”

It has puzzled me that we've been told delta is 'more transmissible ' yet the advice remains that 2m is a safe distance, and 15 minutes contact it is needed for a ping

Surely if that's now 10 seconds that would lead to nearly everyone catching it by now?

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Re: Genuine points of uncertainty

Post by Herainestold » Sun Jul 25, 2021 8:16 pm

Trinucleus wrote:
Sun Jul 25, 2021 7:52 pm
Herainestold wrote:
Sun Jul 25, 2021 6:26 pm
“At the start of this pandemic, I spoke about 15 minutes of close contact being a concern. Now it looks like it’s five to 10 seconds that’s a concern. The risk is so much higher now than it was only a year ago.”

It has puzzled me that we've been told delta is 'more transmissible ' yet the advice remains that 2m is a safe distance, and 15 minutes contact it is needed for a ping

Surely if that's now 10 seconds that would lead to nearly everyone catching it by now?
It would be a lot of pings. Everybody will catch it, the question is how quickly will it happen?

The 15 minutes, two metres is no longer relevant with aerosolized delta. Its more like 10 seconds, 10 metres.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by Millennie Al » Mon Jul 26, 2021 1:42 am

Herainestold wrote:
Sun Jul 25, 2021 8:16 pm
The 15 minutes, two metres is no longer relevant with aerosolized delta. Its more like 10 seconds, 10 metres.
It's not about time and space: it's about air flow and dissipation. If you're outdoors with even a gentle breeze, what you exhale is rapidly spread out over three dimensions making it harmless. If you're in an enclosed space with poor ventilation, you can exhale, leave the room, and still be a danger to someone who arrives minutes later. Unfortunately, this is difficult to explain, scary, and wasn't realised early enough to prevent the simplistic advice taking hold.
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Re: Genuine points of uncertainty

Post by sTeamTraen » Mon Jul 26, 2021 10:51 am

Millennie Al wrote:
Mon Jul 26, 2021 1:42 am
Herainestold wrote:
Sun Jul 25, 2021 8:16 pm
The 15 minutes, two metres is no longer relevant with aerosolized delta. Its more like 10 seconds, 10 metres.
It's not about time and space: it's about air flow and dissipation. If you're outdoors with even a gentle breeze, what you exhale is rapidly spread out over three dimensions making it harmless. If you're in an enclosed space with poor ventilation, you can exhale, leave the room, and still be a danger to someone who arrives minutes later. Unfortunately, this is difficult to explain, scary, and wasn't realised early enough to prevent the simplistic advice taking hold.
Yes, and our noses are quite sensitive. The fact that you can smell someone's perfume or cigarette smoke doesn't mean that a large number of virus particles are arriving at the same time.
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Re: Genuine points of uncertainty

Post by Herainestold » Mon Jul 26, 2021 4:25 pm

Indoor smoking should be allowed again as it allows the observer to see how the ventilation in the room is working. If you can see smoke accumulating anywhere, get out. If you can't see any smoke, nor smell it, the room may be safe. (If you are double masked)
Delta changes everything.

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Re: Genuine points of uncertainty

Post by jdc » Mon Jul 26, 2021 4:46 pm

Yes, can everyone please expose themselves to a lethal cocktail of more than 4,000 irritants, toxins and cancer-causing substances in order to protect themselves from a virus that might not even be present.

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Re: Genuine points of uncertainty

Post by WFJ » Mon Jul 26, 2021 5:00 pm

Herainestold wrote:
Mon Jul 26, 2021 4:25 pm
Indoor smoking should be allowed again as it allows the observer to see how the ventilation in the room is working. If you can see smoke accumulating anywhere, get out. If you can't see any smoke, nor smell it, the room may be safe. (If you are double masked)
Why do you mention double masking in almost all of your posts? Cloth masks are basically useless, whether you use one or two. Using a cloth mask to help seal a surgical mask might help you to stop spreading the virus if you are infected.

If you main concern is protecting yourself, a single FFP2 or FFP3 mask, without any other mask over the top, will give the best protection.

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Re: Genuine points of uncertainty

Post by headshot » Mon Jul 26, 2021 5:06 pm

Herainestold wrote:
Mon Jul 26, 2021 4:25 pm
Indoor smoking should be allowed again as it allows the observer to see how the ventilation in the room is working. If you can see smoke accumulating anywhere, get out. If you can't see any smoke, nor smell it, the room may be safe. (If you are double masked)
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Re: Genuine points of uncertainty

Post by Herainestold » Mon Jul 26, 2021 5:26 pm

WFJ wrote:
Mon Jul 26, 2021 5:00 pm
Herainestold wrote:
Mon Jul 26, 2021 4:25 pm
Indoor smoking should be allowed again as it allows the observer to see how the ventilation in the room is working. If you can see smoke accumulating anywhere, get out. If you can't see any smoke, nor smell it, the room may be safe. (If you are double masked)
Why do you mention double masking in almost all of your posts? Cloth masks are basically useless, whether you use one or two. Using a cloth mask to help seal a surgical mask might help you to stop spreading the virus if you are infected.

If you main concern is protecting yourself, a single FFP2 or FFP3 mask, without any other mask over the top, will give the best protection.
Double masking ( cloth over medical) is recommended by the CDC in America as being more effective and was also recommended in India during their recent wave. FFP2 or 3 are also effective and could be worn. Either alternative is better than a single mask especially cloth mask.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by Herainestold » Mon Jul 26, 2021 5:33 pm

jdc wrote:
Mon Jul 26, 2021 4:46 pm
Yes, can everyone please expose themselves to a lethal cocktail of more than 4,000 irritants, toxins and cancer-causing substances in order to protect themselves from a virus that might not even be present.
Well, when discussing about aerosol spread, one of the analogies is the way tobacco smoke accumulates in a room. It is useful because we can all visualize it. If you are inside a room you can't see the ventilation, but you can see smoke. Except that nobody smokes inside anymore.So if it were allowed on a temporary basis for the duration of the pandemic, it would allow people to evaluate the risk inside. Tobacco smoke is very harmful but the harm comes from repeated exposure over many years, while even a ten second exposure to covid delta can result in an infection.
Delta changes everything.

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Re: Genuine points of uncertainty

Post by WFJ » Mon Jul 26, 2021 5:37 pm

Herainestold wrote:
Mon Jul 26, 2021 5:26 pm
WFJ wrote:
Mon Jul 26, 2021 5:00 pm
Herainestold wrote:
Mon Jul 26, 2021 4:25 pm
Indoor smoking should be allowed again as it allows the observer to see how the ventilation in the room is working. If you can see smoke accumulating anywhere, get out. If you can't see any smoke, nor smell it, the room may be safe. (If you are double masked)
Why do you mention double masking in almost all of your posts? Cloth masks are basically useless, whether you use one or two. Using a cloth mask to help seal a surgical mask might help you to stop spreading the virus if you are infected.

If you main concern is protecting yourself, a single FFP2 or FFP3 mask, without any other mask over the top, will give the best protection.
Double masking ( cloth over medical) is recommended by the CDC in America as being more effective and was also recommended in India during their recent wave. FFP2 or 3 are also effective and could be worn. Either alternative is better than a single mask especially cloth mask.
Effective at protecting the wearer or others? I thought there was very little evidence that surgical masks, with or without a cloth covering, offer any protection to the wearer. Surgical masks do not filter out virus particles, putting cloth over the top does not create a finer filter.

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Re: Genuine points of uncertainty

Post by Herainestold » Mon Jul 26, 2021 5:48 pm

WFJ wrote:
Mon Jul 26, 2021 5:37 pm
Herainestold wrote:
Mon Jul 26, 2021 5:26 pm
WFJ wrote:
Mon Jul 26, 2021 5:00 pm


Why do you mention double masking in almost all of your posts? Cloth masks are basically useless, whether you use one or two. Using a cloth mask to help seal a surgical mask might help you to stop spreading the virus if you are infected.

If you main concern is protecting yourself, a single FFP2 or FFP3 mask, without any other mask over the top, will give the best protection.
Double masking ( cloth over medical) is recommended by the CDC in America as being more effective and was also recommended in India during their recent wave. FFP2 or 3 are also effective and could be worn. Either alternative is better than a single mask especially cloth mask.
Effective at protecting the wearer or others? I thought there was very little evidence that surgical masks, with or without a cloth covering, offer any protection to the wearer. Surgical masks to not filter out virus particles, putting cloth over the top does not create a finer filter.
That is a valid question and I have read arguments for both, but I don't think there is very much high quality evidence.The idea of cloth over surgical is it creates a better seal around the edges of the mask, so you are only breathing filtered air.A new surgical mask has an electrostatic charge that helps it to filter particles, once it is wet it is useless.That is why it is important not to re use medical masks.
Delta changes everything.

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