The Covid-19 Files (6): the Select Committee Actually Replied!

So, back near the dawn of time, it seems, I posted a discussion of how Professor Chris Whitty, the UK’s Chief Medical Officer, apparently had an – how do I put it? outlying? eccentric? – view of the prevalence of Covid-19 in Wuhan and/or Hubei province in China. He bandied around a 20% figure, whereas, to be consistent with the reported mortality rate, only a population equivalent to a low single digit percentage of Wuhan’s 10 million+ population, let alone that of the whole of Hubei, can have been infected.

I explained why this was so important:

Because, if you believe the infection rate in China was 20%, you might imagine that a better prepared health system, such as the UK’s NHS, might be able to cope with an epidemic that ran its course, with a bit of “flattening the curve”,…

Now, did I mention that I wrote to Jeremy Hunt, the Chair of the Health and Social Care Select Committee (“the HSCC”) and former Health Secretary, who actually seems to have a clue what to do, and who asked The Prevalence Question? No? Well, then, this is what I found down the back of the Covid-19 filing cabinet:

From: Tim Joslin
Sent: 12 March 2020 21:52
To: Health and Social Care Committee <>
Subject: Misleading Covid-19 evidence at Select Committee?

Forwarding to address for Select Committee correspondence, as per auto-reply from .

———- Forwarded message ———
From: Tim Joslin
Date: Thu, 12 Mar 2020 at 21:40
Subject: Misleading Covid-19 evidence at Select Committee?
To: <>
Cc: [my MP]


Like millions of people in this country I have elderly parents and many friends who may be vulnerable to the disease, so I am extremely worried by the Covid-19 pandemic.  Come to think of it, I’m no spring chicken myself!

It was encouraging to see on Channel 4 News this evening that you appreciate the gravity of the situation and do not consider the “delay” plans announced by the government today to be adequate. 

The whole approach being adopted doesn’t seem to me to be at all appropriate to the threat we face.  Professor Whitty speaks as if the peak of the epidemic in the UK is an exogenous phenomenon.  It is not.  The UK epidemic will peak at a time and a level determined by the action we take.  Simply put, the sooner we go into “lockdown”, which is something we are inevitably going to have to do, the sooner the epidemic will peak (there will be a timelag of about two weeks between decisive action and a reduction in cases, as seen in China, Italy and South Korea).

Whitty seems to think the Wuhan epidemic somehow reached a “natural” peak, and today used this to claim the virus was unlikely to infect the “worst-case” of 80% of the UK population.  This makes no sense to me because the infection rate in China was determined entirely by the drastic action ordered by their government. 

Which brings me to Whitty’s Health and Social Care Select Committee evidence on 5th March.  In response to a question from you, the Professor appeared to claim that the infection rate in Wuhan (or Hubei – it’s not clear exactly where he was referring to) was 20% and he went on to speculate why that might be the case.  The infection rate even in Wuhan simply cannot have been more than a few percent given there have only been around 3,000 deaths in the whole of China.  [I have posted on my blog a possible explanation of why Whitty thought the rate could be 20% – see Appendix below]. 

Did you think Whitty was claiming a 20% infection rate in the Chinese epidemic? 

The Chinese and Italian health systems have not been able to cope with an infection rate of more than a few percent without drastic “lockdown” measures.  Ours won’t either.  

And if we have to “lockdown” – as we will – when a few percent of us have had the disease, the UK’s strategy of developing “herd immunity” is based on a false premise.

Whitty seems to be somehow (unconsciously) trying to fit the facts into a conceptual framework of a natural epidemic that can be controlled according to a predefined plan (our plan is for flu epidemics, so off the shelf), whereas in fact the epidemic in China was barely natural, the dominant factor was the control measures.  And we in the UK simply cannot allow the epidemic to reach its full potential, since that implies around 500,000 fatalities. 

Besides waiting until we have “herd immunity” in the UK, the only other stable equilibrium point until a cure or vaccine is deployed is eradication of the virus, so eradicate it we must. 

I am writing to you in your capacity as Chair of the Health and Social Care Select Committee, copying in my MP.  I’d be grateful to receive any form of reply.


Tim Joslin

cc. [my MP]




I wrote a comment piece earlier today in the hope that someone would publish it.  Since I hope my text is circulated widely, I include the relevant excerpt (the full article is on my blog at ) in case you want to comment on what I’ve written:

[followed by the text of “Utter Madness” from “A further clue to the government’s thinking…” to the end].

And here’s the reply that I received a few days ago:

Health and Social Care Committee 25 Mar 2020, 10:39 (6 days ago)

to Health, me

Dear Tim,

Thank you for your email.

Chris Whitty provided oral evidence to the Health and Social Care Committee on Thursday 5 March 2020 in connection with the Committee’s inquiry into “Preparations for Coronavirus”. The transcript from this session can be found on the Committee’s website. In reply to Q13, Chris Whitty said that the proportion of the prevalence rate of coronavirus in Hubei is “around 20%”. Following the session, Chris Whitty explained that he had misspoken and that he meant to instead say “under 20%”. The transcript has now been amended to reflect this (see footnotes 1 and 2).

The Committee takes its responsibility to hold the Government, NHS England, Public Health England and other bodies to account very seriously during the current pandemic. As such, the Committee has held oral evidence sessions to assess what work is currently being done to ensure the UK is sufficiently handling the coronavirus outbreak. You can view the transcripts from these sessions, and announcements relating to the Committee’s on going work in this area, by visiting the Committee’s website. During these oral evidence sessions, I will of course endeavour to represent the views of the public and ensure matters such as those that you have raised are answered.

You can view the Government’s latest advice and guidance here. You may also wish to contact the Government Department for Health and Social Care at the following address:

Department of Health and Social Care

Enquiries Unit
39 Victoria Street

Tel: 0207 210 4850

Best wishes,
Jeremy Hunt
Rt Hon Jeremy Hunt MP
Chair, Health and Social Care Committee 
House of Commons | London | SW1A 0AA

The Committee provide a link to the transcript of the proceedings (it’s the file dated 10th March), which, incidentally itself includes a link to the Parliament TV coverage (if you want to watch The Prevalence Question listen from 9:22:40), which I mention because the iPlayer version I linked to in my previous posts (Utter Madness and Did Whitty Mislead?) is going to be taken down at 11:45am this coming Saturday, 4th April.

I checked the HSCC transcript (‘cos I’m a suspicious kind of guy) and it’s fine – just the odd repetition and “you know” left out.

Here is the relevant text:

Q13 Chair: May I move on to prevalence rates? You mentioned that in China the rate is starting to go down. What is the overall prevalence rate for the disease in Hubei province in China? What proportion of the population got it, or have got it so far?

Professor Whitty: You made this point very well on the radio, if I may say so, a couple of weeks ago: the reported proportion is probably somewhere around 20%[1]. That contrasts with our reasonable worst-case scenario that 80% of people could get infected, which we might want to come back to. I think this raises three possibilities, which are not mutually exclusive.

The first is that there is a large iceberg of people who have asymptomatic infection—so a very large number of people have been infected in Hubei without being detected. The reason we do not detect them is that we do not currently have a serological test that can say, “This person has been infected, even though they never had symptoms.” The one thing that would help me, along with all my other colleagues in Public Health England and the NHS, more than anything else in terms of planning for this is to know what proportion of people get the infection and have no symptoms at all, because that would potentially completely change the way we think this is going to go.

That is one possibility. The second possibility is that the extraordinary efforts of the Chinese state have pushed it down to about 20%[2], but when they take their foot off the brake the epidemic will surge back again. That is the second possibility. The third possibility is that it tops out at less than 50% for one of a number of epidemiological reasons.

Any of those are possible. My own view is that it is a combination of the first two—some of the people who are counted currently as not having had it actually have had it with no symptoms, and some of it is to do with the remarkable efforts of the Chinese state and people, but we will not know until we have a serological test. Once we know what that number is in Wuhan and Hubei, that will change the way everywhere else in the world views this, in one direction or the other.

Q14 Chair: Is there any reason why you would expect a higher proportion of the population to get the virus in the UK than in Hubei province, or is 20% the most likely upper end projection?

Professor Whitty: The caution I would have is to remember that the Chinese state and people are still doing some pretty extraordinary things, so we may not have reached the end of this particular outbreak in Hubei. It may be that when they stop doing them, the percentage will go up again. So I think we need to be careful. The straight answer to your question is that I see no reason in theory why the UK would go higher than China, but—the third caveat—if you are doing reasonable worst-case scenario planning, which you will know, having been Secretary of State for Health and Foreign Secretary and having had many other senior roles in Government, you always start off with the highest number that is possibly plausible for planning, because you do not want to be surprised. Then, as you get more information, the numbers gradually come down. The highest number for any new virus which has essentially come out of nowhere to infect humans is about 80%, because after that it runs out of people: every time there is an infection, they are surrounded by people who are immune. So we would always put 80% as our starting point, and then if it turns out that in fact it is not so much that 80% may not get infected, but it may be that of those, 70% of the 80% actually get it without any symptoms at all. At this point, we do not know. Therefore, for that reason, we are doing in a sense a more conservative planning assumption.

[1] Professor Chris Whitty has clarified that he meant to say ‘under 20%’

[2] Professor Chris Whitty has clarified that he meant to say ‘under 20%’

I simply do not know what to make of the footnotes. They seem a bit irregular, but I don’t spend a lot of time reading Select Committtee evidence transcripts.

Lucky Whitty isn’t in charge of HS2: “Go around Birmingham!”, later, “Obviously I meant, under Birmingham”.

It’s like someone being goaded on by his mates: “You can take him! He’s under 6ft!” One would assume from such an exchange that the protagonist was at least 5′ 9″, not a two foot six 4 year-old child!

I’m also baffled when the footnote was added. Did Whitty review the text as part of the normal process? Isn’t he rather busy right now for this to be a priority? Was it in response to my email (and maybe other feedback)? There’s no modification history associated with the document.

The point is that the Chinese data, as I explained before suggests 4% prevalence in Wuhan, tops. Whitty (and presumably his team) suggest 20%.

It’s worth bearing in mind that that Times article (paywall) suggests:

A week earlier, councils had been warned to expect about 100,000 deaths from Covid-19. Now Chris Whitty, the chief medical officer, and Sir Patrick Vallance, the chief scientific adviser, realised their estimates were wrong.

“Unmitigated, the death number was 510,000,” a senior figure said.”

Maybe we’d have been a bit better prepared if we’d realised somewhat sooner that we were going to have to switch from a mitigation to a containment strategy. Assuming, of course that that is indeed what we’ve done – a point Uncharted Territory intends to address in the coming days.