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To think the science behind Chris Whitty’s quoted 1% CFR and therefore the UK Action Plan is wrong

5 replies

MetalDog · 07/03/2020 01:45

Long time MNer but serial name changer.

Apologies in advance if everyone’s already seen this, but I just haven’t had time to keep up with the main thread - huge thanks to all the knowledgeable and regular posters, I really appreciate reading up on everyone’s thinking whenever I get a chance. Also apologies this is so long but if no one’s spotted this document yet, I think it’s import to read the science behind Chris Whitty’s 1% CFR and the UK’s relatively weak response.

Here’s the link to the document, which you can find as a reference in the UK government’s Action Plan. Currently it has a few crossed out sentences, possibly unedited track changes, I don’t know.

In summary, the document details how to change a CFR of over 30% (yes really) to less than 1% by using “nifty” modelling that relies upon a huge hidden iceberg of unidentified cases. You know, the iceberg that Dr Bruce Aylward and his team found no evidence for, as stated in the WHO-China Joint Mission report and the related press briefing, including the evidence that China was testing (if memory serves me correctly - it was mentioned during the press briefing) 50,000 people a day during the Wuhan peak.

This document seems to be the evidence for Chris Whitty‘s assertion that the CFR is 1% and is the science that underpins the UK’s plan. A plan that puts all our eggs in one basket, a basket that relies upon there being a mass of asymptotic and undiagnosed mild cases in China. It explains Chris Whitty’s constant reference to this being a mild disease and the UK’s lackadaisical approach.

Of course, unlike the modelling, there is nothing wrong with the actual formula used in the document, it is the same one promoted on the Worldometer site:

Divide the number of deaths on day X, Y or Z by the number of cases on day X, Y or Z minus 7 days

If the scientists had used the formula with more recent data, they could have demonstrated that the initial very high CFR (the document refers to a CFR of 33%) had continuously fallen reaching 3.7% by around February 24th (not far off the WHO’s recently updated CFR of 3.4%). But of course a CFR of 3.7% is still far worse than the Spanish flu, which is used as a comparator in the document, and is certainly not as palatable as 1%.

This actual, rather than manufactured, drop from the report’s CFR of 33% to 3.7%, could be argued to be a correction of the high number of deaths caused by the Wuhan crisis: according to the WHO-China Joint Mission report, the CFR is context dependent and was therefore much higher in Wuhan due to the health services being overrun.

Another possible explanation pertains to the two CV19 strains identified: the fall in CFR may be due to the less virulent of the two strains making it out of Wuhan, allowing it to gain traction in the rest of the world, effectively creating two separate CFRs, one for Wuhan and one for the rest of the world (I am mindful of Italy and Iran, but there is not enough evidence at the moment to know one way or the other regarding different strains or overrun services).

Now for the really shitty news, using the correct formula you can see that after falling for so long the CFR is now rising. By 28th Feb it’s 3.8%, by 1st March 3.9% and as of 3rd March it’s 4%.

Actually, maybe I’m wrong, if anyone wants to check my figures for themselves (I know there are plenty of highly able maths types here and I am certainly not one of them) please come back and tell me I’m wrong, the CFR did not just hit a low of 3.7% and then start going up again as I’d be really grateful. Not least because I honestly do not know how anyone could spin the fact that the CFR is rising again into a good news story. Even if the CFR is lower in reality (after all we don’t know with 100% certainty the accuracy of the underlying data reported on Worldometer), if I am right, the trend IS there, falling, falling, falling but, since just before the end of February, rising consistently again. It’s hard not to worry, however, that the implication of this is that the Wuhan crisis is no longer influencing the CFR, which bottomed out at 3.7% due to the majority of the world not getting with the required programme.

Our Chief Medical Officer, however, agrees with this document’s CFR of 1% and stated in his BJ press briefing that there’s a big iceberg of unreported mild cases and that CV19 is a mild disease for the vast majority. There was no mention of the moderates within that comforting 80% mild figure, nor any mention of how those people caring for confirmed cases having to self isolate at home can protect themselves without PPE or training, no mention of how you should decide when your mild pneumonia is now serious enough to warrant hospitalisation (but don’t worry someone will chat to you each day, so I’m sure they’ll be able to listen to your chest using their stethoscope down the phone, although that’s assuming they’re even medically trained)... I could go on but instead I suggest you consider doing any of the following actions if you haven’t already done them:

a) read the document I link to above,

b) read the WHO-China Joint Mission report (linked to in the main thread) and listen to Dr Bruce Aylward’s press briefing on YouTube,

c) read our government’s own Action Plan, again you can find a link to it on the main thread (remember the document I link to above is one of the references from that Action Plan),

d) decide whether you think the evidence shows that:

China (despite dropping the ball initially) did in fact create history by flattening and more critically curtailing an epidemic before its own natural peak and therefore saving some proportion of lives and slowing down the spread around the world as outlined in the WHO-China Joint Mission Report meaning that the actions suggested within the report would be useful for our own country to follow as closely as possible.


Our Chief Medical Officer is correct (my interpretation of his message is): “the numbers of cases in the UK will inevitably go up and there’s nothing we can do about that except delay it for a while and, despite there being no evidence that CV19 will behave like seasonal influenza, let’s pray summer sorts us out and saves a few otherwise likely “goners”, never mind, overall it’s a mild disease, the CFR IS 1% (and who’s going to read or learn from the WHO-China joint mission report that quotes a CFR for China of 3.8% whilst citing there is no evidence indicating a hidden iceberg of unreported cases, certainly not me, even though it was out days before my press briefing with BJ). No, our scientific evidence shows CV19 isn’t even as bad as Spanish flu and that’s a much better message.

e) if your answer to d) is:

I wish this country would follow the scientific advice being given by the WHO-China joint mission team. After all, they are doing their upmost to play this down/keep everyone calm and focussed, whilst also saying, loudly and repeatedly:
‘mind shift required (you need to use old fashioned containment methods and they work with this virus). Listed here are the best ways to reduce a very concerning death rate because there is no vaccine available for a good while yet. If China can do it, then so can you - please try, because otherwise a ton of people will die unnecessarily.’

Dr Bruce Aylward actually says in the press briefing that China’s CFR of 3.8% could give the rest of the world a “false sense of security” ffs.’

then please write to your MP and demand to know why:

the UK isn’t closely following the guidance and advice set out in the WHO-China joint mission report,

our Chief Medical Officer is reliant upon and using out of date and inaccurate data to communicate with the public and inform government policy

Please then add any of your own specific concerns and suggestions because, as stated by Dr Tedros, this is “not a drill.”

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tud41 · 07/03/2020 04:30

CFR of 3.7% is still far worse than the Spanish flu, which is used as a comparator in the document, and is certainly not as palatable as 1%.

Can we just remember that when we talk about Spanish flu that the life expectancy was around 50 years old in 1918 anyway so anyone over 40 would have been considered elderly. so the CFR for Spanish flu is really irrelevant when using it to compare for this one.

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Horehound · 07/03/2020 04:38

There was a professor who said that if somewhere reports 500cases the reality is it's more like thousands so I do think the iceberg is right

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nellodee · 07/03/2020 06:02

Neither of the alternatives are entirely pleasant.

If the WHO are correct, China is an honest reporter. This means the CFR is higher, but it is possible to curb the spread.

If the WHO did not dig deeply enough, then the CFR may be lower, but then if the figures from China are not to be trusted, have they really stopped the growth of the virus there?

I hope there is a third scenario. The WHO didn’t do a very good job of investigating. There were a larger number of unreported cases in China, but their containment strategies arrested the spread of both known and unknown cases. The figures are inaccurate but the direction of travel is genuine.

This is my best if both worlds optimism, meaning it’s both containable and that the CFR is lower.

I’ve not read a convincing source for the under 1% figure but I’d be very happy if someone could post a link to a paper showing how that figure is arrived at from recent data.

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tud41 · 07/03/2020 06:10

The WHO surely only went into China to study figures on the reported cases and hospital admissions.. they wouldn't be going house to house asking to test everyone who showed the slightest sign of illness.

Put it this way. if i was in China, seeing how they treated suspected cases, if i thought i had the virus i would just be sat tight in my bed not mentioned it to anyone.

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SSW101 · 07/03/2020 07:23

The CFR is population and time dependent. And comparing it to mortality rates of older pandemics such as the Spanish flu is like comparing apples and oranges. We won't know the true mortality rate until we have the actual number of cases globally once this is over.

The CFR is going to vary as different populations are infected. In Italy, there is a high percentage of elderly people in the population so for a smaller number of cases there will be a higher number of deaths. The virus probably isn't deadlier - the sample population is just different.

The report will have made the best estimate using the UK's population demographics if that is any comfort.

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