Open this photo in gallery Prince Charles and Camilla, Duchess of Cornwall, are seen in a file photo. The 71-year-old heir to the British throne is showing mild symptoms of COVID-19 and is self-isolating at a royal estate in Scotland with his wife, who has tested negative. Jens Meyer/The Associated Press

Prince Charles has tested positive for the new coronavirus and is self-isolating in Scotland as questions swirl about whether the Queen may have been infected.

The Prince of Wales, 71, “has been displaying mild symptoms but otherwise remains in good health and has been working from home throughout the last few days as usual,” said a statement Wednesday from Clarence House, his London residence. His wife, Camilla, Duchess of Cornwall, 72, has tested negative.

Both were tested Monday and got the results late Tuesday. They are now self-isolating at Birkhall, a cottage on the Queen’s Balmoral Estate in Scotland. “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,” Clarence House added.

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The last public event Prince Charles attended was in London on March 12, when he hosted a reception and dinner to support relief efforts for the Australian bush fires. Earlier that day, he had attended assorted events at Buckingham Palace but followed non-contact rules put in place to avoid the spread of the virus.

Buckingham Palace confirmed that he also met with the Queen that day. However, doctors believe he was not contagious until the following day. It’s not clear how that assessment was made or whether the Queen, who is 93, has been tested.

“Her Majesty The Queen remains in good health,” the palace said in a statement, adding that the Queen was “following all the appropriate advice with regard to her welfare.”

Prince Charles hosted a WaterAid summit at Clarence House on March 10 and met with Prince Albert of Monaco, who announced last week that he had tested positive for the virus. ​

The World Health Organization has estimated it usually takes about five days for someone infected with the virus to show symptoms. “The risk of catching COVID-19 from someone with no symptoms at all is very low,” the WHO says in its guidance. “However many people with COVID-19 experience only mild symptoms. This is particularly true at the early stages of the disease. It is therefore possible to catch COVID-19 from someone who has, for example, just a mild cough and does not feel ill.”

There have been questions about whether Prince Charles received preferential treatment, since testing in Scotland is only supposed to be carried out on seriously ill people who require hospital care. Health officials said Prince Charles qualified for a test partly because of his age.

Britain has more than 8,000 confirmed cases of COVID-19, and 422 people have died. The numbers have been increasing rapidly in recent days, and on Monday Prime Minister Boris Johnson ordered a near total lockdown of the country for at least three weeks. The government has also told everyone older than the age of 70 to remain at home.

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Members of the Royal Family have been taking precautions, and many have moved out of London.

The Queen and Prince Philip, 98, relocated to Windsor Castle last week after reports that a member of the Buckingham Palace staff had tested positive for the virus. The palace declined to comment on that case but said in a statement: “In line with the appropriate guidance and our own processes, we have taken the necessary actions to protect all employees and people involved.”

The Duke and Duchess of Cambridge have moved to Anmer Hall on the Sandringham Estate in Norfolk with their children, Prince George, Princess Charlotte and Prince Louis.

Prince Harry and Meghan Markle returned to Canada after completing their final events as royals in London. The couple attended a Commonwealth Day service at Westminster Abbey on March 9 and then flew with their son, Archie, to a home on Vancouver Island, where they have been living since announcing their break from royal duties. ​

Not everyone has been happy to see Prince Charles and other royals leave London for the British countryside. “My parents live in rural NE Scotland,” tweeted Adam Ramsay, editor of Open Democracy, a website dedicated to social and political issues. “They are at risk and will rely on the stretched NHS if they do get COVID-19. Charles Windsor explicitly ignored requests to stay away, risking the lives of countless others so he can be somewhere with a nice view. It’s fair to say I’m angry.”

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