The pandemic is behind us, but we are not done reflecting on what’s been done right or wrong. There is still much to say about the effects of lockdowns, writes Paul Ormerod
The Royal Society is the world’s oldest independent scientific academy. Last week, some of its scientists trespassed onto public policy with a report on how effectively lockdowns and other measures such as mask wearing reduced the number of cases during the Covid-19 pandemic.
At one level, the work was thorough and scrupulous. More than fifty scientists scrutinised 151 leading scientific papers which had estimated the impact of lockdowns in many different countries. On average, these found that lockdowns reduced cases by 50 per cent.
Using refined scientific language, we can say that this conclusion is trivially true. But with all due respect to the august nature of the institution, it is, to use a demotic phrase, a statement of the bleeding obvious.
The fundamental differential equations which govern the spread of any virus were set out by two Scottish scientists almost 100 years ago. The models have become more sophisticated over time, but the basic principles remain unaltered.
In essence, the proportion of the population which catches the virus, Covid-19 in this particular case, depends upon the probability of becoming infected with a single exposure and the number of times an individual is potentially exposed to it. The latter is simply the amount of social mixing, a phrase which became well known during the pandemic.
Lockdowns restrict the amount of social mixing, thereby reducing the number of cases. But this is at best a very partial story, for at least two reasons. The real questions are whether lockdowns reduced the number of cases by more than people themselves would have done on a purely voluntary basis and if so, did these benefits exceed the costs.
Throughout the whole of human history, people have reacted to viruses by cutting back their social encounters. During the incredibly virulent Black Death of the 14th century, for example, town gates were shut and barred to outsiders. Members of the nobility flitted from one castle to another to try and avoid the plague. But even with just a bad case of the common cold, for example, people often either stay at home or warn their work colleagues and friends that they have it.
Fortunately, we do have a real-life counter example during the pandemic in the form of Sweden. Legal restrictions there were minimal, and the government simply provided the population with information about Covid-19 and left it up to them to decide how to adjust their behaviour. And Sweden has come out of it exceptionally well.
The Royal Society boffins did, to be fair, note that in countries with lighter restrictions “a change in case numbers corresponded with large voluntary drops in people’s movements”.
But the scientists appear to have made no serious attempt to address the question of whether compulsion did it better.
They did state that “future work should quantify the social and economic costs of such measures”. Indeed, we might reasonably ask why the report itself did not consider these. A growing body of evidence is showing beyond doubt that the costs greatly exceeded the benefits.
A key point ignored by the study are the excess deaths created in the period beyond the pandemic by the lockdown measures themselves. In short, although at one level the Royal Society’s report is careful and measured, it is a very partial assessment. And it is one which is ultimately irresponsible, creating as it does the impression that lockdowns were beneficial.