Prince Charles has tested positive for the novel coronavirus, aka COVID-19, and is now self-isolating in Scotland, according to a statement released by his office on Wednesday.

He is only experiencing mild symptoms and is otherwise in good health, said Clarence House. However, it is unclear how the Prince of Wales caught the virus due to his recent schedule of public events.

His mother, Queen Elizabeth II, remains in good health and has been “following all the appropriate advice with regard to her welfare,” according to a spokesperson of Buckingham Palace.

It is also unclear why Prince Charles was advised that he was not contagious earlier.

According to a royal source, he could have been exposed to the virus before he saw the Queen on March 12.

A source told CNN, Prince Charles was tested on Monday and received the results on Tuesday.

Prince Charles’s office said, “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.”

After his last public event on March 12, the 71-year-old has had a few private meetings with individuals, who have been made aware of the situation and advised to take precautions.

According to the source, he is self-isolating at his Scottish residence of Birkhall in Aberdeenshire, with a few staff members that are kept separated from him.

“His wife Camilla, the Duchess of Cornwall, is self-isolating separately,” according to Clarence House. “She has been tested and does not have the virus.”

The source also said he has not been to a hospital and was tested due to his age and medical history.

Last week, the palace said the Queen was canceling all public events “as a sensible precaution.” The palace also said they she and her 98-year-old husband, Prince Philip, moved to Windsor Castle on Thursday. On March 13, Prince Charles and his wife said they were canceling their spring tour because of the growing concerns over the coronavirus pandemic.