The palace said Britain's longest reigning monarch, 95, is experiencing mild cold-like symptoms and that she expects to continue light duties at Windsor Castle over the coming week.

“She will continue to receive medical attention and will follow all the appropriate guidelines,” the palace said in a statement.

The queen is fully vaccinated, having received three shots of a coronavirus vaccine.

Earlier this month, Prince Charles tested positive for COVID-19. It was the second time he contracted it. Four days later, Duchess Camilla tested positive. Both are fully vaccinated and had received a booster shot.

The palace did not say whether either had recently met with the queen.

People in the U.K. who test positive for COVID are required to self-isolate for five days, a restriction that the British government intends to lift this week for England.

As the news spread, senior British politicians sent get-well messages. Prime Minister Boris Johnson tweeted: “I’m sure I speak for everyone in wishing Her Majesty The Queen a swift recovery from COVID and a rapid return to vibrant good health.” Opposition Labour Party leader Keir Starmer wished the queen "good health and a speedy recovery. Get well soon, Ma’am.”

In October, the queen spent a night in the hospital for unspecified "preliminary investigations" and after she "regretfully" canceled two other much-anticipated in-person appearance on doctors' orders, according to palace statements.

She then spent two weeks resting at Windsor Castle where she has mostly been living since the start of the COVID-19 pandemic in spring 2020. She kept up with "light, desk-based duties."

The queen marked 70 years on the throne on Feb. 6. She was proclaimed queen on that date in 1952 when her father, King George VI, died at Sandringham, the monarch's estate in Norfolk, following surgery for lung cancer.

The palace released a new picture of the queen to commemorate the occasion, showing her smiling broadly and wearing a pale green dress, sitting in front of one of her red despatch boxes containing government papers, with a picture of her father by her side.

What's the difference between queen and 'Queen Consort'? Camilla's future title, explained
A new picture of Queen Elizabeth II to mark her Accession Day was released on Feb. 6, 2022, by Buckingham Palace. Smiling broadly, she is sitting in the Saloon at Sandringham with one of her red despatch boxes of government papers, with a picture of her father, King George VI, by her side.

A new picture of Queen Elizabeth II to mark her Accession Day was released on Feb. 6, 2022, by Buckingham Palace. Smiling broadly, she is sitting in the Saloon at Sandringham with one of her red despatch boxes of government papers, with a picture of her father, King George VI, by her side.

The day before, she held a low-key reception for locals and volunteer groups in the ballroom at Sandringham, where she cut a cake featuring the Platinum Jubilee emblem. Photos from the gathering show her smiling, joking and unmasked, wearing a pale blue dress embroidered with daisies at the waist, pearls and what appeared to be a platinum double flower brooch. She cut the cake while holding a walking cane, her ever-present black purse over her arm.

Her lengthy reign will be celebrated with a four-day Platinum Jubilee of parties, parades and pageants to begin June 2, when the weather is (usually) better.

The queen has a busy schedule of in-person engagements in the weeks ahead, including a diplomatic reception at Windsor Castle on March 2 and the Commonwealth Service at Westminster Abbey on March 14. On March 29, she has a remembrance service at Westminster for her husband Prince Philip, who died in April 2021 at age 99.

On the eve of the anniversary of her accession, the queen issued a message of gratitude to her people and to her family, and said for the first time that her "sincere wish" is that Duchess Camilla of Cornwall will be known as "Queen Consort" when Prince Charles succeeds her.

"And when, in the fullness of time, my son Charles becomes King, I know you will give him and his wife Camilla the same support that you have given me," her message read, according to the statement issued by Buckingham Palace. "And it is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service."

Her announcement about Camilla provided some finality to the longstanding question of what to call the former Camilla Parker Bowles, once so controversial for allegedly breaking up Charles' marriage to the late Princess Diana that she used the Duchess of Cornwall title instead of Princess of Wales.

The queen's jubilee arrives after a series of personal crises. Last week, her son Prince Andrew settled out of court with accuser Virginia Roberts Giuffre, who says she was sex trafficked to the prince by disgraced financier Jeffrey Epstein when she was 17. Andrew, who has vigorously denied the allegations, agreed to pay an undisclosed sum and donate to Giuffre's charity in support of victims' rights.

The Duke of Edinburgh, the queen's husband of 73 years, died last spring at the height of the pandemic. Strict social distancing rules forced her to sit alone during the funeral service, a spectacle that touched many who had also suffered bereavement amid COVID.