LONDON - The UK could see 50,000 new coronavirus cases a day by mid-October without further restrictions, the government's chief scientific adviser has warned.

Sir Patrick Vallance said that "would be expected to lead to about 200 deaths per day" a month after that.

The briefing at Downing St comes as Prime Minister Boris Johnson considers whether to introduce further measures in England.

On Sunday, a further 3,899 daily cases and 18 deaths were reported in the UK.

Speaking alongside the government's chief medical adviser, Prof Chris Whitty, Sir Patrick said: "At the moment we think the epidemic is doubling roughly every seven days.

"If, and that's quite a big if, but if that continues unabated and this grows doubling every seven days... if that continued you would end up with something like 50,000 cases in the middle of October per day.

"50,000 cases per day would be expected to lead a month later, so the middle of November say, to 200-plus deaths per day.

"The challenge therefore is to make sure the doubling time does not stay at seven days."

Prof Whitty added that a rise in hospital inpatient cases indicated the potential for an exponential increase in deaths if allowed to carry on unabated.

He said that since the start of September, inpatient cases were doubling at around the same rate as infections, every seven or eight days.

"If this continued along the path that Patrick laid out, the number of deaths directly from Covid... will continue to rise, potentially on an exponential curve, that means doubling and doubling and doubling again.

"And you can quickly move from really quite small numbers to really very large numbers because of that exponential process.

"So we have, in a bad sense literally turned a corner, although only relatively recently."(FA)