Defeating SARS-CoV-2

Treatments and their effectiveness, herd immunity, masks, testing, etc.
thinksaboutit
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Joined: Wed Jan 06, 2021 11:38 am

Re: Defeating SARS-CoV-2

Post by thinksaboutit »

amanuensis wrote: Tue Mar 16, 2021 4:20 pm
thinksaboutit wrote: Tue Mar 16, 2021 2:16 pm
amanuensis wrote: Tue Mar 16, 2021 11:26 am

The IFR depends on vulnerability/age. It is likely significantly below 0.1% in the non-vulnerable under 40. It is likely below 0.1% for the non-vulnerable aged 40-50, and only slightly above for 50-60. (lots of sources out there, but this one came up first: https://gh.bmj.com/content/bmjgh/5/9/e003094.full.pdf)

Unfortunately you're right about the proportion of vulnerable in the UK. About 15% are in the 70+ group which has a significant IFR, and a significant number of these will be in the co-morbidity group (very much higher IFR). For the <70 group there's still a large proportion that are vulnerable through co-morbidity. I'd be surprised if the proportion of vulnerable in the UK populaton was under 25%.

That said, it seems rather odd to make 100% suffer when similar effects could be obtained by making 25% suffer. It is doubly weird to put so much focus on the young, when the psychological impact on that group is likely to be very negative (we are measuring 'success' through a very limited lens of 'covid case numbers').
We are in a position where close to 0.2% of the whole population have been killed by Covid (or died within 28days of a positive test, but closely matched by the rate of excess deaths. Since 100% (or anywhere near to that) of population has not been infected, the IFR must be well above 0.2% for the UK population as a whole.

Here is an extract from the bullet points in the article you referenced.

► Using variation in demographics, comorbidities and
health system capacity, we predict COVID-19 IFRs
for 187 countries, ranging from 0.43% in Western
Sub-Saharan Africa to 1.45% in Eastern Europe
This is a disease where there is a subset of the population that is known to be vulnerable (dominated by age).

To quote only population wide IFR is not helpful (indeed, it is misleading) as it substantially overestimates risk for the non-vulnerable (leading to overestimation of threat with consequential overcompensation in behaviour, worry, etc) and substantially underestimates risk for the vulnerable (leading to vulnerable groups behaving in a more risky fashion) -- there are actually relatively few members of the population that have a personal IFR of about 0.2% (perhaps those 50-60 years old and healthy).

The point made originally was that we could relax lockdown for the non-vulnerable and they would have a relatively low death rate (that might be tolerable). Their (serious) mistake was to assume that only 1% would be affected by this when it would have been closer to 25%.

But the point that the death rate in the non-vulnerable would be relatively low is accurate.

Whether that low IFR would be acceptable to the population in return for a partial return to normality for them is a debatable point (and it should be debated).
When someone makes a sweeping statement that 99.9% survive, then that's the whole population is the subject. I object to sweeping falsehoods, especially when they are obviously so.

I take your point that the risk varies wildly between sections of the population. This is obviously correct. A 20 year old has a vanishingly small chance of getting ill, but can still be infected and pass it on to others.

The thought of protecting the 25% who are vulnerable was the basis of the Great Barrington Declaration, which did not bother to consider if this was in any way plausible. A little time considering of how interconnected and interdependent people are shows that what happens in the general population would reach the "protected". They need to visit 30 year old doctors on the outside, and 40 year old carers come to their homes or other institutions. Those outsiders have friends and family on the outside to infect them. The web of risk is vast.

Many of the vulnerable are in key occupational groups, are biased towards ethnic minorities, as well as age and health. Would an approach where these are discriminated against really be acceptable? Who would pick them out?

Luckily, the GBD "idea" was ignored and we are beyond that point now. The people involved have got their little bit of fame and things moved on.

amanuensis
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Joined: Sun Feb 14, 2021 1:32 pm

Re: Defeating SARS-CoV-2

Post by amanuensis »

MikeAustin wrote: Tue Mar 16, 2021 4:37 pm
amanuensis wrote: Tue Mar 16, 2021 4:20 pm This is a disease where there is a subset of the population that is known to be vulnerable (dominated by age).
Indeed. On the same basis, we find many young people are dying of old age.
That's an odd comment.

I think your point is that we all eventually become part of a vulnerable group (perhaps 'hopefully').

That's fine. In the event that the 'right thing to do' is to vaccinate only the vulnerable in order to minimise the risk of vaccine escape then people would be vaccinated as they entered the vulnerable group (if they've not already picked up enough immunity via prior exposure, etc). Then they would benefit from boosters as appropriate.

I don't know for sure that this is the right approach, but it should be considered alongside the current 'vaccinate everyone' approach (that as I've described previously could well lead to an increased risk of vaccine escape compared with restricted vaccinations).

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MikeAustin
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Joined: Thu Aug 27, 2020 2:27 pm

Re: Defeating SARS-CoV-2

Post by MikeAustin »

amanuensis wrote: Tue Mar 16, 2021 9:42 pm
MikeAustin wrote: Tue Mar 16, 2021 4:37 pm
amanuensis wrote: Tue Mar 16, 2021 4:20 pm This is a disease where there is a subset of the population that is known to be vulnerable (dominated by age).
Indeed. On the same basis, we find many young people are dying of old age.
That's an odd comment.
Well, perhaps I am an odd person.
I used an absurdity to support your comment on the unhelpfulness of quoting an average for a population with a vulnerable subset. The young simply cannot die of old age, although an average may be calculated to include them.

amanuensis
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Joined: Sun Feb 14, 2021 1:32 pm

Re: Defeating SARS-CoV-2

Post by amanuensis »

MikeAustin wrote: Wed Mar 17, 2021 12:51 am
amanuensis wrote: Tue Mar 16, 2021 9:42 pm
MikeAustin wrote: Tue Mar 16, 2021 4:37 pm

Indeed. On the same basis, we find many young people are dying of old age.
That's an odd comment.
Well, perhaps I am an odd person.
I used an absurdity to support your comment on the unhelpfulness of quoting an average for a population with a vulnerable subset. The young simply cannot die of old age, although an average may be calculated to include them.
Ah, in that case apologies -- my interpretation was off.

We are of course all odd people -- it is just a matter of identifying where the oddness lies :)

miahoneybee
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Joined: Tue Sep 22, 2020 8:26 pm

Re: Defeating SARS-CoV-2

Post by miahoneybee »

Short and sweet and spot on Mike A 😉 as it this..

https://twitter.com/athenaamerica88/sta ... 22374?s=28

:)

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MikeAustin
Posts: 1045
Joined: Thu Aug 27, 2020 2:27 pm

Re: Defeating SARS-CoV-2

Post by MikeAustin »

amanuensis wrote: Wed Mar 17, 2021 8:51 am We are of course all odd people -- it is just a matter of identifying where the oddness lies :)
"Eee, there's nowt so queer as folk, except me and thee. And even thee's a little odd."

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