The UK government could have protected the lives of more elderly people by allowing the young to catch coronavirus, a leading scientist has said.
Professor Graeme Ackland, who has written a report in the British Medical Journal, said that closing schools was effective at slowing down the spread of the disease, but resulted in more deaths overall than if schools remained open.
Lockdowns have short-term gain, but lead to long-term pain, he suggested.
As a second wave takes hold across the UK and Europe, with new lockdowns being considered, Prof Ackland said that attaining herd immunity swiftly was the best way to keep the total death toll down unless a vaccine were discovered.
The professor of computer simulation at Edinburgh University told The National that to save lives it would be better for a higher proportion of young people to be infected because they have less chance of dying, and it would protect the elderly in the long term.
This would allow for herd immunity, commonly believed to be achieved when 40 per cent of the population is infected.
Severe lockdowns would only suppress the disease, with the current second wave soon followed by a third and fourth unless a vaccine arrived within a year, the report said.
The Edinburgh University report also suggested that if social distancing were relaxed among the under-70s, it would lead to fewer deaths among those older.
It re-analysed modelling work done by Imperial College London at the beginning of the outbreak, which is said to have played a major role in the government’s decision to order a lockdown in March. It predicted 500,000 deaths if there was no intervention, but said no mitigation strategy would be able to keep the death toll below 200,000.
“If you take it that it’s inevitable 40 per cent will get the disease, then the way to minimise the number of deaths is to arrange it such that the people who are not going to die are the people who get the disease,” Prof Ackland said.
The report predicted that over the entire course of the pandemic, keeping schools shuttered would increase deaths by between 80,000 and 95,000. Social distancing the entire population, rather than just shielding the over-70s, could cost between 149,000 and 178,000 lives.
A change in coronavirus strategy has also been called for by a group of international scientists to let young and healthy people resume a normal life while protecting the vulnerable.
The so-called Great Barrington Declaration, drawn up by three academics from Oxford, Stanford and Harvard universities and signed by hundreds of other scientists, also argued for letting Covid spread in low-risk groups to achieve herd immunity.
Worldwide there have been 36.2 million infections and 1,057,000 deaths from Covid-19, including 42,515 fatalities in Britain.
It is suggested that a short, sharp shock of infection could be the best way to ultimately keep the death rate down.
"Closing schools reduces the reproduction number of Covid-19 but with the unexpected effect of increasing the total number of deaths," said the report titled Effect of School Closures on Mortality from Coronavirus Disease 2019.
“Isolation of younger people would increase the total number of deaths, albeit postponed to a second and subsequent waves.”
The report predicted that between 15 and 40 million people would become infected with no immediate vaccine.
With a mortality rate of 1 per cent, that would lead to 200,000 deaths.
“if you can manoeuvre those 20 million people to the younger population then you may be able to reduce the number of deaths," said Prof Ackland, 58.
Under current Covid modelling, the report said social distancing among every age group reduced the number of infections “but increased the total number of deaths, compared with social distancing of over-70s only”.
On this basis, it would be better to allow younger people to become infected with minimal social distancing, thereby establishing a herd immunity that would protect the old.
The report suggested that the national lockdown had only delayed the long-term damage of Covid-19 but had prevented the National Health Service's intensive care beds from being overwhelmed.
But the lockdown, the report said, did “prolong the epidemic, in some cases resulting in more deaths long term”.
This happened because Covid deaths are “highly skewed towards older age groups” and without a vaccine “none of the proposed mitigation strategies in the UK would reduce the predicted total number of deaths below 200,000”.
Just before the lockdown in March, the British government had a choice as to whether to save lives or protect the NHS.
"What the modelling was telling them was, you have to make a choice,” Prof Ackland said.
“Do you want to save lives or do you want to save the NHS? Which do you want to prioritise?
"It was a horrible decision they had to make and it appears that they've gone with saving the NHS."
But he said the choice would be a correct one if a successful vaccine were to be developed within a year.
“The caveat to this report is that if there is a vaccine now and nobody else dies then it was probably quite sensible to close schools," Prof Ackland said.
"But if there isn't a vaccine it was a bad idea because there will be a second wave, which is happening now.
"And if government interventions suppress the second wave as strongly as they suppress the first one, then there'll be a third wave and maybe a fourth.”