Saturday, April 18, 2020

Government ministers are trying to gaslight us again: no, the UK death toll is not "lower than the modellers expected". It's considerably higher.

As you may have seen, BuzzFeed have another exclusive - this time a supposed leak of the government's exit strategy.  It's difficult to know how much credence to give it, bearing in mind that one key part of it (different treatment for different age groups) was flatly contradicted by Patrick Vallance only a couple of days ago.  However, to the extent that it can be taken seriously, it's a bit of a curate's egg.  There's plenty in it that's pretty alarming, but let's accentuate the positive for a moment: WHO advice on the vital importance of using mass testing and contact tracing to control the epidemic seems to have been accepted, albeit several weeks later than it should have been.  The fact that the penny appears to have finally dropped is underscored by an apparent implication that the lifting of lockdown will have to be delayed if testing and contact tracing capacity isn't up to scratch by the desired date of early-to-mid May (and, let's face it, it probably won't be).

The bad news is that the insanity of "herd immunity by mass infection" still doesn't seem to have been entirely banished - SAGE are apparently saying the final resolution of the problem can only be the development of a vaccine, or herd immunity by infection.  However, that has to be put in the context of modelling that shows herd immunity can only be achieved by two means - either a) by allowing the health service to collapse, resulting in a totally unacceptable number of deaths, or b) by an epidemic so slow that a vaccine would almost certainly be available long before its end.  So to all intents and purposes, there's a de facto acceptance that a vaccine in 12-18 months' time is the way out, and the only remaining question is how many people the government will allow to pointlessly die or become infected between now and then.  I get the troubling sense from the BuzzFeed piece that the number might be a lot higher than most of us would be comfortable with.  However, as this process unfolds it will hopefully become clear from international best practice that there is a 'sweet spot' of moderate social distancing measures and extremely rigorous contact tracing which will allow the economy to function, while still keeping the number of new infections persistently low.  South Korea have been demonstrating for weeks that it's perfectly possible, but if it happens in European countries like Germany as well, the government might finally be forced to take the lessons on board.

There's a suggestion that over-70s and other vulnerable people might be told to avoid social contact for 12-18 months, which sounds completely unsustainable to me.  However, in a perverse way it's reassuring that the idea is being floated, because it's a tacit acknowledgement that herd immunity can't and won't be achieved before the arrival of a vaccine.

There's one part of the BuzzFeed article that made my jaw drop to the floor -

"There is increasing optimism in Whitehall that...the peak of the coronavirus crisis in this country will not be as devastating as feared by modellers a month ago.

Forecasts by government scientists had envisaged the NHS facing a monumental task to not to breach capacity at the peak, with the possibility of the health service running out of intensive care beds and ventilators, leading to tens of thousands of extra deaths.

As Britain approaches the peak, ministers are now quietly confident that this disaster scenario will not happen. Part of the reason is that it is now believed fewer people have contracted the virus than the experts expected, and that the nature of the virus itself is different to their initial understanding, with fewer patients requiring ventilation."

Where to start with such gibberish?  First of all, it wrongly implies there was a single forecast in the modelling for the overall number of deaths.  There was not.  There were radically different forecasts for various scenarios in which the government applied different measures -

1) If the government did nothing, there would be around 500,000 deaths.

2) If the government followed their original herd immunity strategy, by shielding certain groups but otherwise allowing normal life to largely continue, there would be 250,000 deaths.

3) If radical social distancing measures were introduced (ie. lockdown or something approaching it) there would be 20,000 deaths or fewer.

The government chose the third option, so the relevant forecast is 20,000 or fewer - and that has probably already been exceeded if care home and community deaths are taken into account.  With several hundred deaths still being reported every day, we could easily finish this wave of the epidemic with more than double the number of deaths that the modellers predicted.

Not for the first time during this crisis, it looks like government ministers are trying to gaslight us.  They're seeking to persuade us that fewer people have been infected than the modellers expected, when in fact the only reason that's happened is because the modellers persuaded the government to change course and impose a lockdown.  It's beyond my pay grade to know whether it's true that fewer patients than expected are requiring ventilation, but if so it's extremely hard to understand why the mortality rate is so much higher than the modellers predicted for the lockdown scenario - especially given that the public's compliance with the rules has by all accounts been considerably better than the modellers allowed for.


3 comments:

  1. There remains a heavy reliance on models to make our decisions for us. The huge problem with this is that these models are complex, containing so many factors and assumptions and outright guesses. They also lack calibration against real world data because we are doing this for the very first time. Anyone who has ever done any mathematical modelling would be concerned by the weight being placed on the outputs. I am concerned that our politicians don't really understand how weak a foundation they are building strategy upon.

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  2. I'm just so fed up with (a) it taking gvts so long to (allegedly) ping to the WHO advice on test test test /trace erc; (b) offer an explanation as to why they ignored it in the first place; and, (c) state why they are not implementing it immediately now they realise their mistake. There is going to be hell to pay after this is over: for the lost lives and businesses that coold have been avoided. And they could have covered their arses by simply working to the WHO guidance. I just don't understand it. The Scot gvt could move right now to mass testing. If they can't they should state the (true) reasons clearly.

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