The UK could be facing 50,000 new Covid-19 cases a day by mid-October, leading to 200 deaths a day a month later if the current rate of infection is not halted, the Government's chief scientific adviser Sir Patrick Vallance has warned.
Sir Patrick said the "vast majority of the population remain susceptible" to catching coronavirus and the current situation required swift action to bring the case numbers down.
Chief medical officer Prof Chris Whitty said: "What we've seen is a progression where, after the remarkable efforts which got the rates right down across the country, first we saw very small outbreaks, maybe associated with a workplace or another environment, then we've seen more localised outbreaks which have got larger over time, particularity in the cities.
"And now what we're seeing is a rate of increase across the great majority of the country.
"It is going at different rates but it is now increasing."
In a televised press conference together with England's chief medical officer Professor Chris Whitty, Sir Patrick said there was "no doubt" the UK was in a situation where the numbers were increasing among all age groups.
He said: "At the moment, we think that the epidemic is doubling roughly every seven days."
Prof Whitty said there was a need to "break unnecessary links" between households and there was a need to "change course".
Sir Patrick Vallance said that there was good progress being made on vaccines.
He said the UK was in a "good position" and that it was possible that a vaccine could be available by the end of the year in small amounts for certain groups.
"In the meantime we have got to get in control of this," he said.
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