Boris Johnson’s roadmap out of lockdown on 21 June is now in “doubt” as the Indian variant has more than doubled this week.
The roadmap to freedom is now “balanced on a knife” as three quarters of all new cases are of the Indian mutant variant, Professor Danny Altmann of Imperial College London warned.
There are now almost 7,000 cases of the Indian variant in the UK, which is now the dominant strain experts have said.
Professor Altman said, “’m not terribly surprised, I think we’d all seen it coming.
“Frankly, it’s alarming isn’t it?”
Speaking to Sky News the surge of thousands of cases of the mutant virus is “troubling” and warned that the government should “set back our clock.”
He was asked if England meets step four of the roadmap out of lockdown on 21 June, he said, “Hopefully there’s some quite careful thought and mathematical modelling being done into this.
“For my taste at the moment, that looks somewhat in doubt.
‘We really are balanced on a knife edge, but surely from all that we’ve all seen in the last 13 or 14 months we realise how unforgiving and relentless this virus is.
“And you can’t joke around with it with half measures.”
Professor Ferguson said it could be up to a further three weeks before they know for certain if lockdown can end on 21 June.
If the vaccines are effective, and the Indian variant is only up to 30% more transmissible, then a third wave could be far smaller.
Speaking to an event organised by the Science Media Centre in Germany on Wednesday he said, “It’s not how high cases rise, but how quickly.
“If they double every 10-14 days and hospital admissions follow the same trend, then there is a concern.
“We were expecting cases to rise as we relaxed restrictions but if they rise too quickly that’s a problem.”
Professor Ferguson told the BBC’s Today programme the 21 June date now “hangs in the balance.”