Understanding the Lockdown Exit Strategy
- Published
- in Health
In the UK we’re about to enter a further three weeks of lockdown. There’s growing pressure from Keir Starmer, the Labour Party’s new leader, for the Government to explain how we exit that lockdown. A lot of people are looking to technology to answer that, largely in the form of tracking applications. This article was going to be about how well that approach might work, until I remembered that it’s a good idea to understand the problem before trying to solve it. I’ll go into the details of contact tracking and tracing in my next article, but first we need to look at some history to see why we need it.
A good starting point is to look at how the current pandemic compares with the Spanish flu of 1918, because we have been here before. With no vaccine or effective anti-virals, we’re in pretty much the same position as we were a century ago. We’re just treating it very differently. The graphs below provide a simple, visual comparison of a few key indicators from then and now.
The major difference is in the way Governments are handling the crisis. Back in 1918, most Governments saw the arrival of Spanish flu and did nothing. They were generally pretty effective in doing nothing. The medical profession couldn’t do much more. It hadn’t changed significantly since Voltaire had observed that “the art of medicine consists of amusing the patient while nature cures the disease”. Or in more severe cases, killed the patient before the doctor did. Few would have expected much of their doctors or politicians. Everyone alive in 1918 would have known someone with an incurable disease, be that TB, typhoid, polio or smallpox. Flu was one of those things which came along every so often and killed some more people – it’s the way life was. People carried on. They needed to work in order to earn; to earn in order to live. The war had reduced the workforce, so jobs were available – unemployment didn’t go up, as it has now; instead more women joined the workforce. Factories were busy. Millions died, but the economy hardly noticed, setting itself up for the roaring twenties. Politicians largely shrugged off any responsibility, retreating to their country estates until it was over. It’s noticeable how few high profile victims there were. The most well-known was probably Gustav Klimt, who certainly would not have been a household name in 1918. Most people probably blamed God rather than their politicians. That’s assuming they even knew who their politicians were, as most didn’t have the vote and couldn’t read.
Penicillin and the arrival of broadcast media changed all that. In the intervening century since the devastation of Spanish flu, the medical profession has done a very effective job at transforming its public image from that of a medieval guild to television gods who purport to be able to save us from virtually any illness. Politicians realised that they needed to appeal to their electorate if they wanted to maintain their posts. And in return, their electorate developed a mantra of entitlement; in return for paying taxes, we expect to be kept safe. So Covid19 came as quite a shock, when everyone realised that they were as helpless to fight it as they had been a century ago.
Let’s see what happened back in 1918, with no intervention. The Spanish flu pandemic came in three waves, as shown below.
Very early in each wave, hospitals and undertakers were overwhelmed. Corpses stacked up and were buried in mass graves. By the end of the third wave, around a year after it started, the population started to achieve herd immunity and the pandemic faded away.
Today neither politicians nor populace would accept that approach. Eliot captured the feeling in his First Quartet observing that “human kind cannot bear very much reality”. Particularly when you have 24-hour rolling news and social media to bring that reality to every smartphone. Whatever the personal tragedy, no political party can contemplate presenting the outcome as mere statistic. We have a compact that requires Government intervention to try and stop us ever crossing that overwhelming red line. Today that means lockdown and massive spending to support those unable to work as a result of that lockdown.
The principle of lockdown is simple (I’ve covered it in more detail in a previous article). You work out how many ICU beds you have, then, as admissions start to rise, institute a lockdown to limit the spread of the virus, in the hope that you’ll not breach the number of available beds. As cases decrease, you release the lockdown and the whole process can start again.
The problem is that most of the economy stops. Public services, like the NHS, transport, care homes, policing, street cleaning, etc., need to carry on and be paid for, as does food distribution and delivery services. A few, lucky individuals can work at home, but large sections of the economy just stop.
Lockdown and social distancing is all about reducing the infection rate, known as R0, which is the number of people who will catch the virus from each infected person. If you can get R0 below 1, then the number of infections starts to fall. To achieve that, the Government is essentially paying people to stay away from each other. It costs money – a lot of money, and destroys tax revenue. It’s a Faustian pact between Government and populace that wasn’t there in 1919.
If we superimpose the lockdown strategy onto the 1918 strategy, we see how they compare:
With a lockdown strategy, the number of deaths is contained to a number that society can tolerate. In between the lockdown, people can return to work, but with restrictions. Social distancing needs to stay in place to allow a long enough gap between cycles, which will limit the ability of many restaurants to operate and probably preclude most mass entertainment, whether that’s theatre, concerts or sport. Forget holidays and don’t even think about foreign travel.
What that picture doesn’t show is the endpoint. Spanish flu burnt out after the first three cycles because everyone had caught it. They’d either died or developed immunity. It had a finite endpoint. The current lockdown strategy doesn’t. It just has a hope that a vaccine will come along.
If we look at the lockdown cycles, they carry on.
Because each cycle kills tens instead of hundreds of thousands, there are more than enough uninfected people left for multiple cycles of infection, which means that left to its own devices, the pandemic and an On/Off lockdown strategy could last for years. The only effective way to stop it is to develop a vaccine. Few expect that we will get to the point of mass vaccination within 18 months. We may get it down to 12 if we’re lucky, but it could equally take five years, which is about the fastest we’ve ever done it before. By that time, we’d probably have acquired herd immunity anyway. However, the bigger threat is whether our national economies can survive for that long?
It’s not a great picture, which is why it’s rather naïve to demand that the Government comes up with a strategy. Right now, their toolbox is remarkably thin.
They basically have two controls. They can set the acceptable level for deaths, which is done by building more ICU hospitals and buying more ventilators. And they can turn the lockdown on and off as the number of people infected in each wave rises and falls. That’s it.
This is why there’s so much interest in tracing apps and tests. They are not going to solve the long term problem – at the moment, that’s the hope of a vaccine, but they give us the opportunity to change lockdown from being a crude On / Off switch to a more modulated control. Grasping this point is crucial, as we’ll see in the next article. If we can do that, it should mean that we can get more people back to work faster and increase the gap between each pair of infection cycles. If we can achieve that, it means that more of the economy is operating, which pays taxes to buy us more time.
That’s the basics, which are so important to understand, as there is no magic wand to wave. In the next article I’ll look at the reality of tracing apps and testing and how they may be able to help.
As a long term believer(and user) of full PID control, I’m entirely with you on that. I started with proportional, but decided that modulate might be better if this spreads to a non-technical audience. I’ll probably be more technical in the next article.
On reflection perhaps we need to ‘modulate’ the Lock Down by proportional rather than On/Off control ?
Would some sort of ‘rationing’ be effective ?
Most informative article – thank you. I look forward to your next article.
The 50% – 80% variation may well be down to the health of the patient at the point of intubation. Ventilators don’t cure you – they simply give the immune system a little bit longer to try and fight the infection. If you have a surplus of ventilators you can intubate earlier, which probably improves the recovery stats.
The other stat I saw yesterday is that over 90% of those who have die had an underlying health condition, which means they would probably have died within the next 12 months. If you were purely looking at the economics, you’d say that letting them die saves money. Back in 1918, when there were just oxygen masks, that was the de facto outcome. I suspect a lot of people wouldn’t disagree with that now, but it needs a very courageous politician to stand up and say it, not least because the media will parade hundreds of ICU doctors to argue that they are saving lives and don’t want to be portrayed as mass murderers. That’s the consequence of broadcast media. There’s an interesting paper on the 1918 outbreak which points out that in the first wave of infections, there were only a few dozen column inches in the major broadsheets devoted to the pandemic. When Lloyd-George caught it and was confined to hospital there was no daily bulletin, just a statement that “he was a prisoner of Manchester’s not too kindly climate”.
At the moment I think that a lot of policy is scattergun, as no-one knows what will work. That’s not because of incompetence – we just don’t know what will work. Today’s media likes big gestures and ventilators is one of those. As we’ve seen, the early specification for new models were trivial, which is why some of those original orders have now been cancelled. It may be better to concentrate on vaccines, but I suspect that everyone who is competent is already doing that. The issue there is that nothing may come out of it for several years, which is not the story a 24-hour media wants to report. History tells us that it’s surprisingly difficult to develop a vaccine that is effective, but doesn’t harm the patient. We shouldn’t forget the TGN1412 trials at Northwick Park.
That’s the conundrum. At the moment we either let people die or shut down the economy. In the next article I’ll look at some of the tracking options which are being proposed to find a middle way, but all they can do is manage the balance, not provide a final answer.
Hi Nick, thank you. Fascinating article as always. I briefly saw an interview yesterday with New York Gov. Andrew Cuomo, in which he stated 80% of intubations result in death. I had previously heard 50% to 80% depending on country. Which strikes me as an extremely poor return especially considering the amount of treasure now being spend making these machines. Would government / state resources not be better spent developing coherent medical treatments involving drugs / therapy etc? Thoughts?