COVID cases are back to their January peak after surging by a million in a week.
More than 4.2million people had the bug last week, the Office for National Statistics said – close to the 4.3million record two months ago.
It means one in every 16 people in England and Wales is infected ahead of ministers’ plans to scrap free testing next week.
It comes after the UK Health Security Agency found cases where old and new versions of Omicron – BA.1 and BA.2 – have combined to form a new variant.
The mutant may spread ten per cent faster than the current strain, but scientists say they are still studying it.
Professor James Naismith, of Oxford University, said of the current spike in cases: “This wave will burn out simply by infecting everyone who can be infected.
“It is pressuring the health service, but vaccination, treatments and the less severe nature of Omicron mean that, for the vast majority, this will not be life-threatening.”
He added: “I would advocate getting your first, second or third jab today – and for those offered a fourth, grab the opportunity.”
The ONS said 330,000 people are now catching the coronavirus every day.
Government critics urged ministers not to drop public testing next week.
Lib Dem MP Layla Moran said: “Cases and hospitalizations are already rising and we are yet to see the impact that scrapping free tests will have on infection rates.
“Free testing is one of the most effective protections against this virus.”
And a study found Covid patients are twice as likely to die and four times more likely to need intensive care if they catch flu at the same time.
Scientists said hospitals should test for both bugs.
Dr Kenneth Baillie, from the University of Edinburgh, said: “Flu is going to come back, so the risk we found is a very real one for next winter and maybe before.”