Prof John Edmunds, a member of the Scientific Advisory Group for Emergencies (Sage), argued Tier 3 lockdowns – the most severe under Johnson’s system – are unlikely to reduce the reproduction (R) rate below 1, meaning there will still be high community infection rates.
He argued a “circuit breaker” national lockdown, something which Sage recommended last month but Johnson resisted, would hold COVID-19 incidence at a “lower level” and reduce hospital admissions.
It comes a day after the government reported a surge in COVID deaths. There were 241 announced on Tuesday, up from 80 on Monday. This was the highest daily number in four months.
Appearing before the House of Commons science and technology committee on Wednesday, Prof Edmunds said of Johnson’s strategy: “I think we are not being as cautious as I would like us to be. I think it’s pretty clear cases have been going up quite fast.
“What worries me a little bit is where the strategy leads to at the moment, the targeted tiered strategy. If you think it through, where that leads to is a high level of incidence everywhere.
“Let’s say Tier 3 works and keeps the reproduction number at about 1 – I don’t think anyone thinks this is going to reduce it to less than 1.
“That means that in Liverpool and Manchester and the North West [areas which are in Tier 3], it will keep the incidence at this high level which is putting hospitals under strain and causing significant numbers of deaths. We’re going to keep it at that high level now for the foreseeable future.”
Watch: How will England's three-tier local lockdown system work?
R represents the average number of people each COVID-19 positive person goes on to infect. When the figure is above 1, an outbreak can grow exponentially.
He said the Midlands and London could soon go into Tier 3, again only reducing R to 1.
“What that means by logical extension of this,” Prof Edmunds went on, “is that we all end up at a high level of incidence where hospitals are really under stretch and we have large numbers of deaths.
“That for me is the logical conclusion of this strategy that we’re following and I would not follow that strategy.”
He said a “very stringent” circuit breaker national lockdown could “half” COVID incidence, rather than “hold” it.
It comes after Prof Jonathan Van-Tam, the deputy chief medical officer for England, warned an increase in deaths is “baked in” with the second wave of new infections.
Some 21,331 UK-wide cases were recorded on Tuesday, with a seven-day average of 18,231.
Prof Van-Tam warned at the Downing Street press conference on Tuesday: “The key point is that having had a rather flat summer, with very low amounts of COVID-positive patients in the UK, you can see that from early September there has been a marked pick-up.”
He continued: “Already, with the cases that we know about, we have baked in additional hospital admissions and sadly we also have baked in additional deaths that are now consequent upon infections that have already happened.”
However, unlike Prof Edmunds, Prof Van-Tam said he does not support a circuit breaker lockdown.
“Do I think right now it is appropriate to insist on those similar hard measures in, for example, the south-west of England or Kent, where levels of the disease are very, very much lower than in the north of England – the national firebreak you talked about? No, I don’t think that is right.”
Watch: Which areas are in what tier in the UK?