Coronavirus - General Chat - No statistics

[scotia]

The difficulty in calculating IFR is knowing the denominator. The "official report" knowingly overstated the IFR and does not reveal any sensitivity calculations on infections without antibodies. Frankly that makes it tendentious.

Well here's your chance - give us a number for your estimate on infections without antibodies (with appropriate scientific evidence), and apply it to the 1.58% number - then we can see if an "around 1%" ballpark is too high.

[servodude]

The difficulty in calculating IFR is knowing the denominator. The "official report" knowingly overstated the IFR and does not reveal any sensitivity calculations on infections without antibodies. Frankly that makes it tendentious.

unlike say, using the median of the time from infection to death metric when working backwards from peak deaths
- that wouldn't be taking a metric that gives a provably larger value than should be used and knowingly applying it to fit an argument?

as some folk apparently say "it is what it is"
- this is an estimate for IFR given what's known, that states its assumptions, and it should be used accordingly (and will as pointed out hopefully be refined over time)
- some of us normally have to deal with orders of uncertainty/variation and bickering about this margin of error seems like an angels on a pin distraction

lets focus on the real problem; which is people using the word precision when they mean accuracy

- sd

[servodude]

The difficulty in calculating IFR is knowing the denominator. The "official report" knowingly overstated the IFR and does not reveal any sensitivity calculations on infections without antibodies. Frankly that makes it tendentious.

unlike say, using the median of the time from infection to death metric when working backwards from peak deaths
- that wouldn't be taking a metric that gives a provably larger value than should be used and knowingly applying it to fit an argument?

as some folk apparently say "it is what it is"
- this is an estimate for IFR given what's known, that states its assumptions, and it should be used accordingly (and will as pointed out hopefully be refined over time)
- some of us normally have to deal with orders of uncertainty/variation and bickering about this margin of error seems like an angels on a pin distraction

lets focus on the real problem; which is people using the word precision when they mean accuracy

- sd

John you'll enjoy this paper - it covers a study on T-cell vs antibodies in a deep dive
- https://www.biorxiv.org/content/10.1101 ... 888v1.full
and it does look like very good news

What I'm presently trying to glean from it is what ratio of their sample set showed only T-cell immunity (whereas the crux of the paper is showing how efficacious that immunity is)

-sd

[dealtn]

Now Covd-19 is highly infective - so I'm going to propose that each invective contact has a 50% chance of passing over the infection.

I suspect it may not be anywhere near as high as that. If it were it would have swept through the population rapidly, surely, not declined dramatically.

The R number was supposed to be a good demonstrator of that. R was often quoted as between 1 and 2 at the height of the pandemic (from memory) which meant each person passed it on to between1 and 2 others. Now if it was as highly infective as your numbers suggest all carriers, especially the "less careful" asymptotic ones, would have been passing it to multiple others I would think, not just 1 or 2 people over the 14(?) days or so when they were infectious.

[johnhemming]

unlike say, using the median of the time from infection to death metric when working backwards from peak deaths
- that wouldn't be taking a metric that gives a provably larger value than should be used and knowingly applying it to fit an argument?

We cannot say unless we know the profile of the times from infection to death. The only figure we have is the 21/23 days figure. If you know of more than that then please give a reference to it.

Well here's your chance - give us a number for your estimate on infections without antibodies (with appropriate scientific evidence), and apply it to the 1.58% number - then we can see if an "around 1%" ballpark is too high.

Given that the "official report" had a figure of 0.9% then 1% is too high. If you simply take the London reducing figures of 10 and 17 and apply those to 1.58 you get 0.92 and that is a low figure for

wikipedia tries to be balanced and objective
https://en.wikipedia.org/wiki/COVID-19_pandemic

Other measures include the case fatality rate (CFR), which reflects the percentage of diagnosed people who die from a disease, and the infection fatality rate (IFR), which reflects the percentage of infected (diagnosed and undiagnosed) who die from a disease. These statistics are not timebound and follow a specific population from infection through case resolution. Our World in Data states that as of 25 March 2020 the IFR cannot be accurately calculated as neither the total number of cases nor the total deaths, is known.[93] In February the Institute for Disease Modeling estimated the IFR as 0.94 percent (95-percent confidence interval 0.37–2.9), based on data from China.[96][97] The University of Oxford's Centre for Evidence-Based Medicine (CEBM) estimated a global CFR of 0.8 to 9.6 percent (last revised 30 April) and IFR of 0.10 percent to 0.41 percent (last revised 2 May), acknowledging that this will vary between populations due to differences in demographics.[98] The CDC estimates for planning purposes that the fatality rate among those who are symptomatic is 1.1 percent and that 40 percent of infected individuals are asymptomatic, for an overall infection fatality rate of 0.65 percent (0.5 to 0.8 percent).[99][100]

None of those come up to 1% for IFR.

John you'll enjoy this paper - it covers a study on T-cell vs antibodies in a deep dive
- https://www.biorxiv.org/content/10.1101 ... 888v1.full
and it does look like very good news

Its a useful paper which adds to a substantial body of information about T cells and fighting disease.

In the end a lot of information can be gleaned merely from looking at the charts of admissions and deaths. Further if people really did not get some immunity without antibodies then we would have thousands of reported cases of people catching the disease badly.



In the chart you would expect to see a variation from Sweden in England as a result of the lockdown in the UK reducing the infection rate and you do see it around mid April.

[redsturgeon]

Now Covd-19 is highly infective - so I'm going to propose that each invective contact has a 50% chance of passing over the infection.

I suspect it may not be anywhere near as high as that. If it were it would have swept through the population rapidly, surely, not declined dramatically.

The R number was supposed to be a good demonstrator of that. R was often quoted as between 1 and 2 at the height of the pandemic (from memory) which meant each person passed it on to between1 and 2 others. Now if it was as highly infective as your numbers suggest all carriers, especially the "less careful" asymptotic ones, would have been passing it to multiple others I would think, not just 1 or 2 people over the 14(?) days or so when they were infectious.

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

In one case, person A tested positive for antibodies but had had no symptoms and was locked down with their family of three children and a partner. None of the others tested positive.

This suggests the virus not be as infectious as some might think.

John

[johnhemming]

This suggests the virus not be as infectious as some might think.

It is moreso that not everyone is susceptible.

[redsturgeon]

This suggests the virus not be as infectious as some might think.

It is moreso that not everyone is susceptible.

I agree with that too.

John

[Mike4]

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

In one case, person A tested positive for antibodies but had had no symptoms and was locked down with their family of three children and a partner. None of the others tested positive.

This suggests the virus not be as infectious as some might think.

John

Or that other members of the family previously had it and acquired T cell immunity.

[88V8]

..... suppose you are one in about about 50 persons dining, .....it's a good idea to accept restrictions that control the infection rate, so that the elderly can have a reasonable quality of life.

We dine out seldom. And have not done so since the panpanic began. I do not think it worth the risk, whatever level that risk might be. OH is a good cook and enjoys cooking, we have fruit and veg in the garden, we enjoy the fruits of our labour.

But if I did eat out, I would be very picky about where I dined. Somewhere with intelligent, older, customers and staff. We are booked to a country house hotel at year end, been before, believe it fulfils those criteria but even so will be somewhat trepidacious.

Listening to Times Radio this morning, an item about shop workers and the abusive behaviour of some customers re masks. The young, the stupid. I try to avoid such people and especially now, which is why we have forsaken Aldi which we used to alternate with Waitrose.
Don't see us resuming the old normal until we have a viable vaccine.

And the notion that the young should behave is a certain manner to facilitate the old, well, worthy notion, I wish you luck with it

V8 (pushing 70)

[johnhemming]

Or that other members of the family previously had it and acquired T cell immunity.

Or had another coronavirus and got T cell immunity from that.

[Mike4]

Or that other members of the family previously had it and acquired T cell immunity.

Or had another coronavirus and got T cell immunity from that.

Yes that seems more likely.

Which leads to a related subject. Do you know what proportion of common colds in circulation are coronaviruses?

I've read that there are only four CVs in circulation causing common colds (as opposed to 250-ish other viruses), but widely differing opinions about how widespread they are. I've read claims that 50% of common colds are the four coronaviruses, and that only 1% are. This proportion seems pretty important when assessing the likely extent of T cell immunity to SARS-CoV-2 in the general population.

[johnhemming]

This
https://www.webmd.com/cold-and-flu/cold ... old_causes

Says 20%, but probably relates to the USA. I would expect the level of prior infection by coronaviruses to vary from country to country and within countries. However, those tests which looked for the proportion of people with prior resistance came in the 40-60 or 50 range. Hence I work on an initial assumption of 50% susceptibility.

[jfgw]

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

In one case, person A tested positive for antibodies but had had no symptoms and was locked down with their family of three children and a partner. None of the others tested positive.

This suggests the virus not be as infectious as some might think.

John

Or that other members of the family previously had it and acquired T cell immunity.

...but did not pass it on to person A.

This suggests the virus is not as infectious as some might think.

Or had another coronavirus and got T cell immunity from that.

Given that it is quite common for an infected person to not infect other family members, the implication is that there is a high level of prior immunity.


Julian F. G. W.

[scotia]

Now Covd-19 is highly infective - so I'm going to propose that each invective contact has a 50% chance of passing over the infection.

I suspect it may not be anywhere near as high as that. If it were it would have swept through the population rapidly, surely, not declined dramatically.

The R number was supposed to be a good demonstrator of that. R was often quoted as between 1 and 2 at the height of the pandemic (from memory) which meant each person passed it on to between1 and 2 others. Now if it was as highly infective as your numbers suggest all carriers, especially the "less careful" asymptotic ones, would have been passing it to multiple others I would think, not just 1 or 2 people over the 14(?) days or so when they were infectious.

Agreed - probably too large a factor

[Mike4]

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

In one case, person A tested positive for antibodies but had had no symptoms and was locked down with their family of three children and a partner. None of the others tested positive.

This suggests the virus not be as infectious as some might think.

John

Or that other members of the family previously had it and acquired T cell immunity.

...but did not pass it on to person A.

This suggests the virus is not as infectious as some might think.

Or had another coronavirus and got T cell immunity from that.

Given that it is quite common for an infected person to not infect other family members, the implication is that there is a high level of prior immunity.


Julian F. G. W.

The way some people catch COVID-19 apparently out of nowhere, yet others can live with an infected family member yet not catch it, looks very similar to me to the way the common cold spreads. Random and unpredictable.

I do however suspect the measures we are taking to control COVID will turn out to also control the common cold and 'flu. I suspect this coming winter, the number of 'flu cases will plummet. Same with colds.

But this is distracting from the point I was developing earlier, which is that if (say) 50% of the population already has immunity to other coronaviruses and that immunity is effective as now seems to be the case against SARS-CoV-2, then we must be closer to herd immunity threshold than originally thought.

If we started at 50% immunity rather than zero as originally believed, this is incredibly Good News. So determining the proportion of CV colds in the population becomes important for estimating the starting percentage of T cell immunity in the population. So, does anyone have any reliable figures for the the proportion of CV colds Vs other viruses?

[scotia]

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

I would be interested to know if you can you quantify the "quite common" - although I appreciate you may be bound not to release data prematurely.

[redsturgeon]

In our testing we are finding that it is quite common for one member of a household to have had the virus without passing it on to anyone else in the household.

I would be interested to know if you can you quantify the "quite common" - although I appreciate you may be bound not to release data prematurely.

Unfortunately I have to keep things reasonably vague and anecdotal at the moment. I just thought it would be useful to add some stories from the front line so to speak.

John

[Clitheroekid]

In the end a lot of information can be gleaned merely from looking at the charts of admissions and deaths. Further if people really did not get some immunity without antibodies then we would have thousands of reported cases of people catching the disease badly.



In the chart you would expect to see a variation from Sweden in England as a result of the lockdown in the UK reducing the infection rate and you do see it around mid April.

What you also see is that despite there being no lockdown in Sweden - including the fact that all schools remained open quite normally throughout - the number of what might be termed `excess deaths' is tiny compared to the population as a whole. In fact, their Covid death rate per million is actually lower than ours. It's also now fallen to negligible numbers - just 8 in the last week.

And as a result of their sensible attitude their economy has taken `only' an 8.6% hit compared to the rest of the EU - https://www.bbc.co.uk/news/business-53664354 And most of that hit is because of the behaviour of their trading partners in adopting wholesale lockdowns.

This to my mind all goes to support my view that their common sense approach was by far the best, and if it had been adopted by the rest of the world the social and economic damage would have been a tiny fraction of what it will now be.

[johnhemming]

I find it interesting how closely the curves match (much that I have moved one jurisidiction one day). I did expect lockdown to have a demonstrable effect and it does. I think another effect is that our tail of people dying from Covid-19 is extended compared to Sweden.