On Friday I posted what was intended to be a short critique of the UK’s coronavirus plan. We need to eradicate the virus in the UK, not “delay” and “mitigate” its spread. I included towards the end of Friday’s post a section about how the Chief Medical Officer, Professor Chris Whitty, seemed to imply (from 22:47 into this iPlayer recording of his evidence) that China had seen an infection rate of 20% in Wuhan or Hubei province (he is not clear what area he is referring to).
The more I think about it the more significant it seems that Whitty apparently believes the 20% figure.
I don’t believe the infection rate even in Wuhan, let alone Hubei as a whole, was anything like 20%.
Whitty used the odd phrase: “the reported proportion is probably somewhere round about 20%”. Curiously, Google search doesn’t find any significant use of the term “reported proportion” in an epidemiological context.
So what does “the reported proportion” actually mean?
I strongly suspect that, wherever Whitty read or heard the term “reported proportion”, it was intended to mean the proportion of actual cases that were reported, That is, there have not been around 80,000 cases in Wuhan/Hubei, but nearer 400,000. This would tally with the mortality rate, which is usually given as around 3.4% in Hubei (but may ultimately be higher), but less than 1% in the rest of China, as reported by Tomas Pueyo (Charts 13 and 14). The main reason for the difference is presumably that more mild cases were detected in the rest of China, where frantic efforts were made to close down outbreaks caused by travel from Wuhan. Those with mild disease would have simply recovered at home in locked-down Wuhan – I can tell you I for one certainly wouldn’t have tried to go to the hospital there unless I was very seriously ill. (Another reason for the higher mortality rate may be that the medical services in Wuhan were overwhelmed for a period, and couldn’t save as many patients they might have done otherwise, but that would tend to support my argument that the infection rate in Wuhan was a low single figure percentage).
Why is this important?
Actually, it’s not just important. It’s critically 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”, which is obviously a basic tenet of epidemiology, since many epidemiologists use the phrase.
I’m not convinced the NHS is necessarily better resourced than the Wuhan health service and China sent in tens of thousands of medics from other regions to deal with the epidemic, which we’re not actually in a position to do, but that’s not the central issue.
If instead you believe the infection rate in Wuhan, let alone the whole of Hubei province, let alone the whole of China, was only, say 4%, it would be fairly obvious that drastic measures must be taken to stop the spread of the virus. We can’t simply try to manage the epidemic in the UK.
Any talk of hoping “herd immunity” will develop is entirely misplaced, since that would require a 50-90+% infection rate.
In his evidence Whitty went on to wonder whether the infection rate in Wuhan was even higher than 20%. He pointed out that there could have been many asymptomatic cases. He’s right that we don’t know whether or not that is the case. I’m not sure I’d want to gamble tens of thousands of lives on the answer, though! And it’s obviously a much bigger ask if we’re starting from a 4% rather than a 20% infection rate.
The apparent reason Whitty induges in speculation in his evidence is that he seems to think the epidemic in Wuhan was self-limiting. He even goes on to wonder whether the infection naturally only reaches 20% of the population, which from the vast amount I’ve read on the subject over the last few weeks seems extremely unlikely.
I don’t want to resort to hyperbole, but, really, it’s blindingly obvious that the reason more people didn’t catch the coronavirus in Wuhan is because they were all forced to stay in their apartments.
I wonder if Whitty is experiencing cognitive dissonance, and fitting the facts to match what he wants to believe. A parallel might be the failure by those in charge of the Grenfell Tower fire-fighting effort to abandon the “stay-put” policy when it had clearly failed.
It’s not just Whitty who wants to delay the lockdown of the UK. Plenty of other epidemiologists support him. This has implications:
First, Whitty is under peer-pressure. He’s part of a community of epidemiologists.
Second, we may have a groupthink problem. Why would the epidemiological community be so keen on the too-clever-by-99% plan to “flatten the curve” in the UK? (Though there are also loud voices urging a stronger approach).
Well, for one thing it’s what they’ve spent their whole lives studying. Their entire raison d’étre is to provide advice on how to respond to epidemics. I should imagine that the main justification they use in research grant applications, such as to build computer models, is to develop tools that would be valuable in informing the UK’s response to any future epidemic.
The UK’s Coronavirus Action Plan is explicitly for a flu pandemic, maybe something like swine flu in 2009 or a bit more serious like the Asian flu (sorry Asia!) epidemic of 1957-9. Whitty and his colleagues want to put that plan into practice. Maybe it would help in such circumstances, I don’t know.
But the Covid-19 pandemic is outside the parameters for which the UK’s flu epidemic plan can be sensibly applied. The mortality rate is too high and the burden on the health service off the scale. Covid-19 needs to be eradicated. (Or as close to that goal as possible: we need to roll back the current epidemic and stamp on any further outbreaks until we have a vaccine, or at least effective drugs).
I bet the knot-untying community were mightily pissed-off when Alexander pulled out his sword and cut the Gordian Knot. Unfortunately the epidemiology community may have to experience similar feelings if we’re to avoid utter catastrophe in the UK.
Please listen to Chris Whitty’s testimony to the Health and Socal Care Select Committee (as I said, you could start from 22:47 in) and see what page (or planet) you think he’s on.