Prince Charles has tested positive for coronavirus, his household has announced.

A Clarence House spokesman says the heir to the British throne has tested positive and has "been displaying mild symptoms but otherwise remains in good health".

"It is not possible to ascertain from whom the Prince caught the virus owing to the high number of engagements he carried out in his public role during recent weeks."

The spokesman added that his wife, Camilla, has also been tested but does not have the virus.

The Prince, 71, and the Duchess of Cornwall are self-isolating at home in Scotland after the tests were carried out by the NHS in Aberdeenshire, Scotland.

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The son of Queen Elizabeth II and future king of Britain is now the most high-profile patient in the realm. Several members of the UK parliament, sports figures and a prominent epidemiologist have also tested positive.

Prince Charles has been a man in robust health who enjoys physical activity, including hedge trimming and horseback riding. He played polo until 2002, when he retired from the sport.

He is first in line to succeed his mother, the queen. And speaking of the 93-year-old monarch, one of the first questions royal correspondents were asking was: When was the last time Charles saw his mother? And was he infected then?

GETTY IMAGES Prince Charles has mild symptoms of coronavirus.

In a statement, Buckingham Palace said: "Her Majesty The Queen remains in good health. The Queen last saw The Prince of Wales briefly on the morning of 12th March and is following all the appropriate advice with regard to her welfare. We will not be commenting further."

The World Health Organisation says the incubation period for the novel coronavirus can be as long as 14 days.

The queen, her retinue and her faithful corgi, Candy, left Buckingham Palace in London a week ago to hunker down at Windsor Castle, west of the capital.

She was joined by her husband, Prince Philip, who traveled by helicopter from his home at Wood Farm at Sandringham estate in Norfolk. The 98-year-old Philip has retired from public life.

In 1593, the first Queen Elizabeth and her royal court moved to Windsor Castle to escape the ravages of plague in London, and so there is long precedent.

The global pandemic led the queen to cancel a planned state visit by the Japanese royals, the recently crowned Japanese emperor and empress.

She has praised the acts of dedication by health-care workers and said now is the time for everyone in Britain to do their part.

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