Camilla, the Duchess of Cornwall, has tested positive for Covid-19 - just days after her husband Prince Charles.
Clarence House confirmed today that Camilla, 74, had now been hit by the virus and was self-isolating.
A statement from Clarence House said: “Her Royal Highness The Duchess of Cornwall has tested positive for COVID-19 and is self-isolating. We continue to follow government guidelines.”
Camilla is triple vaccinated, sources said.
The duchess carried out a string of engagements last Thursday – the day Charles tested positive for a second time.
Camilla described herself as “luckily” negative the same day, saying of her testing regime during a visit to Thames Valley Partnership in Buckinghamshire: “I’ve taken it so many times”.
On that day, Charles, 73, had been expected to visit Winchester but had to cancel at the last minute.
Aides said the prince was found to be positive during a routine test – which suggested he was experiencing no strong symptoms – but they declined to go into further details on his medical condition.
News of Charles' positive test came just hours after he attended a black tie event held by the British Asian Trust at the British Museum on Wednesday and met scores of people.
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At the event, which he attended with Camilla, he also gave a speech to 350 guests, which included Chancellor Rishi Sunak and Home Secretary Priti Patel.
Meanwhile, concern for the Queen’s health was mounted after it was revealed that the monarch was in direct contact with eldest son Charles two days before he tested positive.
Buckingham Palace said on Thursday that the Queen was not displaying any symptoms, but refused to confirm whether she had tested positive or negative, citing medical privacy.
The 95-year-old spent time with Charles last Tuesday when the prince was carrying out an investiture on her behalf at her Windsor Castle home.
The Queen has been triple-vaccinated so will not need to self isolate, unless she tests positive.
She received her first jab in January 2021 and her second jab in March while sources say it is believed she got her booster jab in October.
Buckingham Palace aides said they would not comment on the Queen’s personal health, but a palace source said “obviously the situation will be closely monitored”.
The Queen is understood to be “feeling much better” recently after regaining her health after a torrid few months.
She was forced to spend the night in hospital in October after receiving treatment for an unexplained condition.
Doctors ordered her to take a period of rest after she completed a relentless schedule of 19 engagements in as many days.
The monarch then missed the Remembrance Sunday service at the Cenotaph in London in November after spraining her back.
Throughout the pandemic, the Queen has largely been shielded by a ring of steel dubbed ‘HMS Bubble’, whereby 22 royal staff sacrificed their home lives to stay isolated at Windsor Castle so they could serve the Queen and her late husband Prince Philip during lockdown.