The SAGE Reasonable Worst Case Scenario (RWCS)

The news this morning is that the government is due to announce a nationwide lockdown on Monday because  deaths are even worse that foreseen in SAGE’s worst case scenario which was leaked 2 days ago. The Spectator on Thursday published the SAGE modelling group’s Reasonable Worst Case Scenario (RCWS). This also explains why Boris Johnson had been so cautious about opening up the economy. France, Germany and Italy have all announced new lockdown measures. Is all this actually justified?

Firstly the UK is actually doing better than the rest of Europe and cases are growing more slowly. They appear also to be levelling off under the current  regional “tier” system.

7-day infections per 100,000 population in different European Countries.

Just as the current measures seem to be working, Boris is under new pressure from SAGE for a new national lockdown because deaths currently exceed that foreseen by their modellers in their RWCS at the end of October.  Their scenario shows the second wave of Covid-19 starting this autumn with a long slow peak lasting until March causing up to 85,000 deaths and a surge in ICU beds . The first version of the RWCS report was published in July. No wonder Boris had been looking so glum and despondent. However, there is something very strange about their model.  I show below a comparison between their modelled cases with those that have actually been recorded so far (October 28). This shows that it is simply their timing that was wrong.

SAGE RWCS modelling of cases (red) compared to recorded cases. The blue curve shows recoded  weekly cases

There is an artificial flat phase in their model lasting for about 6 weeks from October to early November. This implies that the modellers had assumed there would have to be a new lockdown period on 1 Oct followed by a relaxation and then a slow surge in cases. Epidemiological models are fairly straightforward unlike these curves . These models are concerned more about social interactions so the scientists are really trying to be more like social engineers testing measures to restrict contact rates.

Note how if we remove the 6 week flat period then the agreement is fairly good. Deaths and cases are ahead of the RWCS because there was no October lockdown. They also appear to be near the peak and the latest ONS infection survey implies that R is slowly reducing. The turnover point would be when the national value of R reaches 1.0. The fall matched to values of R < 1.

Therefore the current tier system is actually working quite well while maintaining economic activity. A full lockdown may well hasten this process but then at the price of causing irrevocable damage both to the economy and to non-covid health care. It may well be that the final death toll from delayed cancer and heart treatment exceeds that due to Covid-19 itself. Boris should therefore wait another week because the current measures may well be enough. New cases are levelling off. Covid deaths today reflect the situation as it was ~3 weeks ago.

About Clive Best

PhD High Energy Physics Worked at CERN, Rutherford Lab, JET, JRC, OSVision
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6 Responses to The SAGE Reasonable Worst Case Scenario (RWCS)

  1. Douglas Brodie says:

    I agree that a full lockdown would be a disaster.

    Your matching curves are interesting in an academic sense but surely most of the ballooning “cases” are an artefact of the unfit-for-purpose PCR mass testing which yields huge numbers of false positives creating a so-called “casedemic” as described by Ivor Cummins.

    There are currently no excess deaths in any of the four UK countries as is clearly shown on the latest EuroMONO graphs. Deaths are rising slowly and as Mike Yeadon points out they are occurring across all age groups not mainly among the old, they are equally male and female not mainly male and are not mainly respiratory deaths, so they are not mainly due to Covid but more likely the result of lack of NHS treatment over the last six months because of Covid.

    • Euan Mearns says:

      Hi Doug,

      “Yeadon points out they are occurring across all age groups not mainly among the old”

      If you look just at the Covid deaths you find the age stratification is the same as for all deaths. Surprise, surprise, in normal circumstances it is mainly the very old and frail that die. The age stratification of Covid deaths now in E&W is the same as in the first wave.



      • Douglas Brodie says:

        Euan, The point Yeadon was making is that many ill people are ending up in hospital where they are subjected to Covid tests which can result in a true positive (perhaps even contracted since entering the hospital) or a false positive. Either way, when they eventually succumb to whatever is ailing them, it goes down as due to Covid.

        Yeadon doesn’t pull his punches, asserting that the government and Sage are lying to us. The full interview is here:

  2. Euan Mearns says:

    Hi Clive,

    One dimensional policy – sound familiar? I’m actually writing a paper right now on one dimensional UK energy policy.

    Not stressed enough on the telly is the low level of compliance with simple rules. There are sections in our society who simply don’t think the rules apply to them. If you haven’t seen it, I attach the King’s college paper on compliance. I also attach a graph for Scotland where you will see that Aberdeen is probably the least infected city in the UK. One reason for this might be the lockdown we had in August (I was in Zurich) where they seemed to get test and trace working effectively. Elsewhere in the country I don’t think the operators of test and trace have the slightest clue what they are supposed to be doing.

    I like the tier system since this rewards good behaviour and punishes bad. Our local hotels all have open sided tents and we can still wrap up and go out for a meal accompanied by wine with friends.

    Our 5 tier system (0-4) comes into effect on Monday, where 1-3 ~ equivalent to England. What Boris needs is a tier 4 to more severely lock down the areas with high infections. It would be bonkers to abandon the tier strategy without giving it a chance to work.



    @ Doug – that was a great article you wrote the other week. I will send you my excess deaths chart on Tuesday when data released to update it. To 16 Oct there were no excess deaths in the 0-64 age group and 0.6% excess deaths in the >65 group. Hugh Pym at the BBC is trying hard to do a good job and showed his version of this chart but claimed there was 6% excess deaths. What they have done is to take all the Covid deaths and assume these are excess while in fact Covid is killing people about to die from something else. I predict few deaths from flu this year since if you are old and frail and catch flu, Covid will probably kill you first.

    • Clive Best says:

      Hi Euan,

      I completely agree. Despite non-compliance mainly by the young, the tier system is finally beginning to work. The rise in cases has slowed and we could have anyway turned the corner within a week.

      The SAGE modellers are really writing a version of SIM-City. which is not directly related to epidemiolog ! All this was kept secret to avoid any critical examination by others.
      They are now pressuring Boris to introduce a national lockdown as early as Monday which will include Scotland.

      It is ridiculous because it doesn’t try to balance against the health and economic downsides of lockdown.

      • Euan Mearns says:

        Hi Clive, according to this BBC report it is just England. I don’t think Westminster has jurisdiction in Scotland – and it would lead to a revolt N of the Border. Most of Scotland is already under quite stringent lockdown and the data shows this is working with infections falling in most badly affected health boards. Large geographic swathes of the country have infection rates <50 / 100,000 / week – including Aberdeen 🙂

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