Coronavirus - Modelling Aspects Only

[spasmodicus]

Herd immunity might be reached at a great deal lower % than expected.
https://judithcurry.com/2020/05/10/why- ... /#comments

An interesting paper. The discussion which follows it shows just how far we have to go in understanding the dynamics of this pandemic. It's reminiscent of the climate change debate in that reaction to the findings seems to depend heavily on prejudice. We're all gonna die / herd immunity denial versus nah, it's nothing to worry about.

S

[Nimrod103]

I have found the graphs and charts issued by COBR useful over the last few weeks, but I have only located them on the Daily Mail website, which has not carried them for the last two days, Does anyone know where they can be found online?

[dspp]

I have found the graphs and charts issued by COBR useful over the last few weeks, but I have only located them on the Daily Mail website, which has not carried them for the last two days, Does anyone know where they can be found online?

This may help you, it is the link I get in the .gov email each day, slides as pdf and dataset as .xls

https://www.gov.uk/government/publicati ... tent=daily

https://assets.publishing.service.gov.u ... Slides.pdf

for some reason they seem to have gorn from todays. That makes me smell a rat.

regards, dspp

[zico]

Herd immunity might be reached at a great deal lower % than expected.
https://judithcurry.com/2020/05/10/why- ... /#comments

This paper says 58% needed for herd immunity, compared to 70% that Vallance said. Certainly lower, but not that different.

[servodude]

Herd immunity might be reached at a great deal lower % than expected.
https://judithcurry.com/2020/05/10/why- ... /#comments

This paper says 58% needed for herd immunity, compared to 70% that Vallance said. Certainly lower, but not that different.

Certainly not when you consider that the propagation is geometric
- at an "R" of 1.1 that would be less than two days difference

by my reading on the numbers in https://docs.google.com/spreadsheets/d/ ... Y/htmlview
- the daily increase in the 7-day rolling average for covid deaths in the UK did not drop below 10% until the ~7th april
- (using the lemma that deaths are a proportion of infections - which probably holds until the elderly population has gone)

as ever with this bug it's the asymptomatic incubation period being so bloody long that's going to make stuff difficult

- sd

[Mike4]

as ever with this bug it's the asymptomatic incubation period being so bloody long that's going to make stuff difficult

- sd

Or more specifically, that both asymptomatic and presymptomatic people are infectious.

I'd also suggest another (related) problem is the public at large seems only vaguely aware of this fact. Posters on these boards seem very much the exception judging by my own conversations with normal people in real life about C19.

[servodude]

as ever with this bug it's the asymptomatic incubation period being so bloody long that's going to make stuff difficult

- sd

Or more specifically, that both asymptomatic and presymptomatic people are infectious.

I'd also suggest another (related) problem is the public at large seems only vaguely aware of this fact. Posters on these boards seem very much the exception judging by my own conversations with normal people in real life about C19.

Ah! The old "how can I give it to my gran I'm not sick" thing.

I'm pretty sure that if they gave the population some credit the message could be put across more clearly

- sd
(and apologies for using "R" in my last post it's not THAT R (effective propagation ration) rather it was intended to be daily geometric gain)

[johnhemming]

Another article looking at excess deaths.

https://www.npi.org.uk/blog/older-peopl ... -has-been/

[servodude]

Another article looking at excess deaths.

https://www.npi.org.uk/blog/older-peopl ... -has-been/

That was a good read, thanks!

Just wearing the devil's advocate hat for a moment, it claims:

It is also clear from the graph that these “other” excess deaths only started to appear once people started to die from Covid-19. That some of these “other” deaths are really due to Covid-19 but weren’t classified as such must be beyond doubt. But unless all of them were, the inescapable conclusion is that some people have died not as a result of Covid-19 itself but as a result of the way that health and care services have changed to cope with Covid-199

- inescapable conclusion might be over-reaching a bit?
- if this is true, in the way that's expressed in the article, what explains excursions above average in previous years?

I don't disagree completely (I know of at least one death in this category) but I think that worded otherwise this would have sounded less politically motivated (which tends to set off alarms when i read)

thanks again
- sd

EDIT: actually the death I referred to was not due to any changes in health services, tragically it was due to anxiety exacerbated by the thought of the virus

[johnhemming]

I didn't post this for any reason other than information. I think the excess deaths figure is a useful one to identify trends in early Covid death. It is, however, really difficult to get somewhere with it at the lower levels.

The question as to the median time between infection and death is also an issue. Although I have used 21-23 days, I would not be surprised if the median time is actually longer (not mean whilst almost certainly will be when finally calculated). We can then work backwards to try to identify infection levels for say the two bounds of IFR of 0.1% and 1% and then do calculations to assess where infection then went. Although I am of the view that IFR is in the 0.1-0.2 range it is worth doing the calculations for other values.

[Sorcery]

Herd immunity might be reached at a great deal lower % than expected.
https://judithcurry.com/2020/05/10/why- ... /#comments

This paper says 58% needed for herd immunity, compared to 70% that Vallance said. Certainly lower, but not that different.

Figures 4 and 5 are the key ones ion the article.

From the conclusion :
<i>In my view, the true herd immunity threshold probably lies somewhere between the 7% and 24% implied by the cases illustrated in Figures 4 and 5. If it were around 17%, which evidence from Stockholm County suggests the resulting fatalities from infections prior to the HIT being reached should be a very low proportion of the population.<i>

[spasmodicus]

meanwhile, on 14th May the ONS will be publishing the first regular update on its random testing

https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/bulletins/coronaviruscovid19infectionsurvey/england10may2020#covid-19-infection-survey

preliminary results are stated for swab tests conducted in England between 26 April and 8 May 2020

It is estimated that 0.24% of the population in England tested positive for COVID-19 (95% confidence interval: 0.14% to 0.40%).

It is estimated 136,000 people in England were currently infected with COVID-19 (95% confidence interval: 76,000 to 225,000)

it's a pretty modest level of testing, considering that we are more than two months into the outbreak, but at least it's a start. The confidence interval shows a factor of three between max and min cases estimated, but this should narrow with time.

S

[zico]

meanwhile, on 14th May the ONS will be publishing the first regular update on its random testing

https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/bulletins/coronaviruscovid19infectionsurvey/england10may2020#covid-19-infection-survey

preliminary results are stated for swab tests conducted in England between 26 April and 8 May 2020

It is estimated that 0.24% of the population in England tested positive for COVID-19 (95% confidence interval: 0.14% to 0.40%).

It is estimated 136,000 people in England were currently infected with COVID-19 (95% confidence interval: 76,000 to 225,000)

it's a pretty modest level of testing, considering that we are more than two months into the outbreak, but at least it's a start. The confidence interval shows a factor of three between max and min cases estimated, but this should narrow with time.

S

76k-225k is a much lower range than I'd have expected, but it's likely that most people on average have Covid-19 for about 2 weeks, so total over the last 8 weeks would be likely to be maybe 6 times that number (taking into account the numbers infected should be lower than the peak) - though that rough estimate only gives 2 million with the virus.

A much better estimate would be from Vallance who said at yesterday's press conference the government estimate of people infected to date is 10% in London and 4% nationally.
He didn't clarify whether the 4% also includes London or not, but assuming 10m in London and 57 million outside London, total figure would be between 3-3.5 million, so somewhere around 5% of population infected (which of course means 95% of population haven't yet been infected).

[zico]

Herd immunity might be reached at a great deal lower % than expected.
https://judithcurry.com/2020/05/10/why- ... /#comments

This paper says 58% needed for herd immunity, compared to 70% that Vallance said. Certainly lower, but not that different.

Figures 4 and 5 are the key ones ion the article.

From the conclusion :
<i>In my view, the true herd immunity threshold probably lies somewhere between the 7% and 24% implied by the cases illustrated in Figures 4 and 5. If it were around 17%, which evidence from Stockholm County suggests the resulting fatalities from infections prior to the HIT being reached should be a very low proportion of the population.<i>

Thanks for the correction - I'd only skimmed it very quickly so missed that the first graph referred to homogenous populations.

I've read it a bit more carefully now, and although it's too dense for me to fully understand it, I have 3 major objections.

1. "Sense test 1". UK scientific advice has been that benefits from herd immunity are only achieved at 60%+ levels. If the author (Nic Lewis) is correct, than most UK scientists are wrong. Possible, but unlikely, unless he's a world-renowned scientist with a track record of being correct with his minority views. So, how good are the author's scientific credentials and is he recognised as a leading scientist? Which brings us to point 2.

2. "Sense test 2". From Wikipedia.

Nic Lewis. A semiretired successful financier from Bath, England, with a strong mathematics and physics background, Mr. Lewis has made significant contributions to the subject of climate change

So he is not a scientist. He is however a climate change denier, which puts him at odds with over 99% of actual scientists. Again, maybe he's right and virtually all scientists are wrong, but doesn't seem too likely.

3. In his quote below, he makes the big assumption that because the new cases had stopped increasing by 11th April, HIT (Herd Immunity Threshold) had been reached. But surely new cases could stop increasing for a variety of other (and more likely) reasons? Greater public awareness, practising social distancing, hand-washing, fewer people out and about.

Very sensibly, the Swedish public health authority has surveyed the prevalence of antibodies to the SARS-COV-2 virus in Stockholm County, the earliest in Sweden hit by COVID-19. They thereby estimated that 17% of the population would have been infected by 11 April, rising to 25% by 1 May 2020.[5] Yet recorded new cases had stopped increasing by 11 April (Figure 1), as had net hospital admissions,[6] and both measures have fallen significantly since. That pattern indicates that the HIT had been reached by 11April, at which point only 17% of the population appear to have been infected.

[zico]

ONS Coronavirus stats now out for England & Wales, up to week ending May 1st (week 18).

https://www.ons.gov.uk/peoplepopulation ... ng1may2020

It's clear the deaths have passed their peak. More interestingly, the report show graphs by region, and it's clear that all regions have also passed their peak.

England & Wales excess deaths are now 46,494 more than 5-year average for weeks 13-18 (period since the epidemic hit the UK).

Number of Covid-19 deaths (not excess deaths) for week 18 alone were 1,494 in total,
Of those 1,494 people
- 11 were people aged 35 years or less (0.74% of all Covid-19 deaths)
- 52 were people aged 45 years or less (3.5%)
- 202 aged 55 or less (13.5%)
- 564 aged 65 or less (37.8%).

So 37.8% of all deaths were people 65 or under. That's high, but almost certainly because 65+ folks are self-isolating rather than going out to work.

By a statistical coincidence, 37.8% is also the percentage of care homes deaths involving Covid-19. It's not unreasonable to assume that means 37.8% more people dying in nursing homes than normal. There have now been 8,312 care homes deaths involving Covid-19.

[dspp]

I have found the graphs and charts issued by COBR useful over the last few weeks, but I have only located them on the Daily Mail website, which has not carried them for the last two days, Does anyone know where they can be found online?

This may help you, it is the link I get in the .gov email each day, slides as pdf and dataset as .xls

https://www.gov.uk/government/publicati ... tent=daily

https://assets.publishing.service.gov.u ... Slides.pdf

for some reason they seem to have gorn from todays. That makes me smell a rat.

regards, dspp

It would appear my nose for detecting rats is on target, and there is something whiffy in No10,

https://www.theguardian.com/world/live/ ... -continues - see 14:35

"No 10 fails to commit to resuming publication of global deaths comparison chart in daily slides
Andrew Sparrow Andrew Sparrow
The Downing Street lobby briefing has just finished. Here are the main points.

The prime minister’s spokesman refused to confirm that the government remained committed to publishing its usual daily slides, including the global deaths comparison chart. The government did publish slides yesterday, but not the usual ones including a slide showing a global deaths and another showing transport use. The spokesman said he could not say whether these slides would be used again. The government would be showing slides about the roadmap to recovery, he said. The transport use slide was moderately awkward for the government because last week it showed a small but steady increase in people travelling at a time when that was not being encouraged. Here is the one from Saturday last week.
..
But ministers were particularly embarrassed by the global deaths comparison chart. Even though it compares countries that compile their figures in different ways, and it gives total deaths not deaths per head, it looked damning because it showed the UK as having the worst death rate in Europe - and, as the days went on, this became more prominent. Here is the chart from Saturday.
.."

- dspp

[dealtn]

I have found the graphs and charts issued by COBR useful over the last few weeks, but I have only located them on the Daily Mail website, which has not carried them for the last two days, Does anyone know where they can be found online?

This may help you, it is the link I get in the .gov email each day, slides as pdf and dataset as .xls

https://www.gov.uk/government/publicati ... tent=daily

https://assets.publishing.service.gov.u ... Slides.pdf

for some reason they seem to have gorn from todays. That makes me smell a rat.

regards, dspp

It would appear my nose for detecting rats is on target, and there is something whiffy in No10,

https://www.theguardian.com/world/live/ ... -continues - see 14:35

"No 10 fails to commit to resuming publication of global deaths comparison chart in daily slides
Andrew Sparrow Andrew Sparrow
The Downing Street lobby briefing has just finished. Here are the main points.

The prime minister’s spokesman refused to confirm that the government remained committed to publishing its usual daily slides, including the global deaths comparison chart. The government did publish slides yesterday, but not the usual ones including a slide showing a global deaths and another showing transport use. The spokesman said he could not say whether these slides would be used again. The government would be showing slides about the roadmap to recovery, he said. The transport use slide was moderately awkward for the government because last week it showed a small but steady increase in people travelling at a time when that was not being encouraged. Here is the one from Saturday last week.
..
But ministers were particularly embarrassed by the global deaths comparison chart. Even though it compares countries that compile their figures in different ways, and it gives total deaths not deaths per head, it looked damning because it showed the UK as having the worst death rate in Europe - and, as the days went on, this became more prominent. Here is the chart from Saturday.
.."

- dspp

I don't know, as I have never seen, but do you think in Belgium and USA they use the total deaths, or death per million charts and international comparisons?

[dspp]

This may help you, it is the link I get in the .gov email each day, slides as pdf and dataset as .xls

https://www.gov.uk/government/publicati ... tent=daily

https://assets.publishing.service.gov.u ... Slides.pdf

for some reason they seem to have gorn from todays. That makes me smell a rat.

regards, dspp

It would appear my nose for detecting rats is on target, and there is something whiffy in No10,

https://www.theguardian.com/world/live/ ... -continues - see 14:35

"No 10 fails to commit to resuming publication of global deaths comparison chart in daily slides
Andrew Sparrow Andrew Sparrow
The Downing Street lobby briefing has just finished. Here are the main points.

The prime minister’s spokesman refused to confirm that the government remained committed to publishing its usual daily slides, including the global deaths comparison chart. The government did publish slides yesterday, but not the usual ones including a slide showing a global deaths and another showing transport use. The spokesman said he could not say whether these slides would be used again. The government would be showing slides about the roadmap to recovery, he said. The transport use slide was moderately awkward for the government because last week it showed a small but steady increase in people travelling at a time when that was not being encouraged. Here is the one from Saturday last week.
..
But ministers were particularly embarrassed by the global deaths comparison chart. Even though it compares countries that compile their figures in different ways, and it gives total deaths not deaths per head, it looked damning because it showed the UK as having the worst death rate in Europe - and, as the days went on, this became more prominent. Here is the chart from Saturday.
.."

- dspp

I don't know, as I have never seen, but do you think in Belgium and USA they use the total deaths, or death per million charts and international comparisons?

I don't know as I have never gone looking, though I can hazard a guess about the USA one .....

For me in these situations it is most important to see a core of consistent reporting. When politicians start cutting bits out of the core that in itself tells a story. It wasn't just the absent deaths chart that made me suspicious, it was also the absent traffic charts which I use to personally calibrate my personal observations of roads near me.

Excess deaths at UK level (not just E&W) will I suspect now be at the 50,000 level when looking at the ONS data. (https://www.ons.gov.uk/peoplepopulation ... ng1may2020) I do not trust cause of death data from death certificates as I know of too many stories from my own network that throw significant doubt if one just slices the dataset on "cv19". But the self-evident signal in the overall deaths data is unmissable. In due course I would expect that it is this overall signal which will be compared across countries (and any other relevant health care unit) so as to assess efficacy of variations in response strategy.

regards, dspp

[dealtn]

For me in these situations it is most important to see a core of consistent reporting. When politicians start cutting bits out of the core that in itself tells a story.

I tend to agree.

All I would add is that it is human nature to present "the story" rather than the facts, especially from politicians. It has been refreshing that the consistency we desire has been there, pretty much, throughout.

I think that as we move from phase 1 - lockdown, into phase 2 - easing, and beyond, we should expect the presented facts to change. As such I have a little slack to grant the administration on this occasion. I would be wary though should this turn into a wider lack of consistency in presenting the "new" dataset. In which case I would join you in the disappointment that "politics" were taking over from "facts".

[dspp]

For me in these situations it is most important to see a core of consistent reporting. When politicians start cutting bits out of the core that in itself tells a story.

I tend to agree.

All I would add is that it is human nature to present "the story" rather than the facts, especially from politicians. It has been refreshing that the consistency we desire has been there, pretty much, throughout.

I think that as we move from phase 1 - lockdown, into phase 2 - easing, and beyond, we should expect the presented facts to change. As such I have a little slack to grant the administration on this occasion. I would be wary though should this turn into a wider lack of consistency in presenting the "new" dataset. In which case I would join you in the disappointment that "politics" were taking over from "facts".

Maybe the consistency was influenced by the senior person being absent. He's ordinarily incapable, so being complete absent is helpful. Now he is back.

I am afraid I don't cut this lot any slack. Experts are bailing them out. The same experts they ordinarily denigrate. That is why I am so keen to see the same set of charts landing in my inbox every day so I can form my own view.

regards, dspp