The new figures came after Prime Minister Boris Johnson said the UK is "coping very well indeed under the most challenging possible circumstances".
NHS England said on Wednesday night a further 28 people, aged between 47 and 93, have died after testing positive for coronavirus in England, bringing the total deaths in the UK to 465.
The 47-year-old did not have any underlying health conditions, NHS England said.
Speaking at the daily press conference inside Number 10, he added that he wanted to offer a "special thank you to everyone who has now volunteered to help the NHS."
"When we launched the appeal last night, we hoped to get 250,000 volunteers over a few days," Mr Johnson said.
"That is already, in one day, as many volunteers as the population of Coventry."
Earlier Clarence House announced that the Prince of Wales, 71, was self-isolating at home in Scotland with his wife, the Duchess of Cornwall, 72, who does not have the virus.
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