New research has suggested that an early relaxation of the coronavirus lockdown would be more dangerous for older people than younger.
A report from the University of Warwick has suggested that 60-year olds could be 50 times more likely to be killed from COVID-19 than those in their early 20s.
It comes as Boris Johnson prepares to outline a path out of lockdown as he fronts his first daily briefing since he tested positive for coronavirus.
While the prime minister is expected to outline what a loosening of the rules would look like, he is unlikely to be putting any timeframe on the measures.
The report from the University of Warwick says there are “fatality risks” for middle-aged people and older is lockdown is ended too early.
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It states: “If politicians want an imminent removal of the lockdown, the safest approach, in our judgment, would be a rolling age-release strategy combined with the current principle of social distancing.”
A chart from the university – which it stresses is an “extreme worst case scenario” of everyone in the country contracting coronavirus – shows that “it is probable that fatalities among 50-year olds would be 20 times more than among 20-year olds”, while among 60-year olds “the fatalities would be approximately 50 times as great as among those in their early 20s”.
The report warns: “Any lockdown release policy that does not design itself around the extreme ‘age gradient’ in human coronavirus risk is likely to have dangerous consequences for citizens.”
A rolling-age strategy would see the youngest adult age groups allowed more freedom, before the measures are extended to older age groups.
In its recommendation for the approach, the report states: “Crucially, it is the least likely strategy to require that people will have later to be painfully recalled into further rounds of lockdown.”
The UK’s next lockdown review is due next Thursday, and the prime minister has already said that he would not risk harming the current strategy until the government’s five tests for exiting have been met.
Scotland’s first minister, Nicola Sturgeon, said on Thursday that next week may be too early to safely lift any of the coronavirus lockdown restrictions.
Sturgeon said “real progress" has been made on tackling the spread of the virus – but warned these gains are too "fragile" to enable her to be confident that lockdown restrictions can be eased at the next review date of 7 May.