In early March 2020 it seemed that the Covid-19 virus in the UK was spreading exponentially; the fatality rate was unknown and the ability of the NHS to deal with rapidly rising numbers of seriously ill people was unclear.
Estimates made at that time by Professor Neil Ferguson’s team at Imperial College London put the possible level of UK deaths if there was no change in behaviour at 500,000. Based on that and other assessments, the government followed the example of other European countries in introducing severe restrictions on individual movement. The key message was to stay at home; this was a blanket lockdown.
Was the length of this lockdown warranted and should restrictions now be eased significantly?
In recent research, undertaken with medical researchers at Manchester University and at the health consultancy company RES Consortium, we estimated the costs and benefits of the lockdown.
We have found that the costs of carrying on with such a lockdown are likely to become greater — perhaps far greater — than its benefits. We need to move beyond a generalised lockdown to measures targeted at those most at risk.
Any such assessment has to place a value on possible lives saved. There is no way to do this in a way that is clearly ethically justifiable, empirically reliable and widely accepted. One approach is to focus on quality-adjusted life years (Qalys) that may have been saved.
The NHS has established guidelines about how much should be spent on medical treatments that on average yield benefits in terms of life years saved. This effectively values a Qaly at £30,000. One can use that rule with estimates of lives that might have been saved due to the restrictions and compare those with the costs of lockdown.
Those costs go well beyond a simple focus on GDP lost. Health costs from telling people to stay at home are likely to be large and long lasting. Referrals for cancer investigations were 70 per cent down in April 2020; there were hardly any follow-up routine appointments for long-term conditions in UK primary care between mid-March 2020 and the beginning of June; the number of outpatients seen was 64 per cent down and elective admissions to hospitals fell 75 per cent; attended appointments in general practice were down 35 per cent. The impact of the stress of the lockdown on anyone with a pre-existing mental health condition, let alone the population as a whole, is yet to be determined.
Suppose one took a very favourable set of assumptions about a widespread lockdown that lasts three months. Suppose that without this lockdown that required people should not leave their home there would have been no change in behaviour at all (wildly unlikely) and that the estimate of 500,000 deaths with no change in behaviour made by the team of Professor Ferguson is accurate.
The lockdown could then have saved around 440,0000 lives — the 500,000 deaths net of 60,000 estimated deaths that have occurred. Assume those who would have died lose ten quality-adjusted years of life (Qalys) on average (though in fact those who might have died are likely to have had substantially lower life expectancy). Using the £30,000 figure generates a value of potential years of life saved of £132 billion.
What is the lowest plausible estimate of the cost of the lockdown? Suppose we only count lost GDP. The Office for Budget Responsibility and the Bank of England has put this at 13-14 per cent of GDP if restrictions are eased now and the economy bounces back.
If we ascribe only two thirds of this lost GDP to the lockdown, this generates a cost of £200 billion. This cost ignores all future lost GDP beyond 2020; it excludes all medical side-effects (not treating cancer patients, stopping screening for serious conditions, etc); it ignores the future damage of disruption to education.
This is a macabre calculation, but one that puts cost of the extended lockdown high relative to benefits. It is also a calculation that is hugely pessimistic about what would have happened in terms of lost lives with no blanket lockdown, since people would have taken precautions even if not instructed to stay home.
But why use that £30,000 figure per Qaly as a guide to how much we should pay for policies that might save years of life? The £30,000 figure is used in decisions within the UK health system; it is not an arbitrary number. It is not based on likely future earnings lost or the value of future consumption — calculations that are open to the moral objection that they reduce the value of human life to how much people would have spent on commodities.
Instead it is what is considered the highest level of spending that should be used in the UK health system to generate extra quality-adjusted years of life — and it is the saving of lives that the lockdown is for.
In using this yardstick, one is treating decisions on how to face Covid-19 in the same way as decisions in the UK are made about treatments for cancer, heart disease, dementia, diabetes and many other health conditions. On that basis it would seem as though the benefits of continuing with the lockdown are lower than its costs.
A case can be made for using much higher values placed on potential good years of life saved. Yet our analysis suggested that even using values three times as high as the Nice guidelines meant that maintaining the blanket lockdown for as long as three months was likely to have taken costs beyond benefits.
The evidence suggests that now we need to normalise how we view Covid because its consequences are comparable to other health problems. A movement away from blanket restrictions that bring large, lasting and widespread costs and towards measures targeted specifically at groups most at risk is now imperative.
David Miles is Professor of Economics at Imperial College London
