Queen Elizabeth, 95, has tested positive for COVID and is experiencing mild symptoms, Buckingham Palace said on Sunday.
"The queen has today tested positive for COVID," the Palace said. "Her Majesty is experiencing mild cold like symptoms but expects to continue light duties at Windsor over the coming week.
"She will continue to receive medical attention and will follow all appropriate guidelines."
Charles, 73, the heir to the throne, earlier this month pulled out of an event after contracting coronavirus for a second time. A palace source said he had met the queen just days before.
The health of the queen, the world's oldest and longest-reigning monarch, has been in the spotlight since she spent a night in hospital last October for an unspecified ailment and then was advised by her doctors to rest.
Elizabeth on Wednesday quipped to members of the royal household that she could not move much as she carried out her first in-person engagement since Charles tested positive.
Thousands of people gathered in Bangladesh's capital Dhaka on Tuesday to mark the first anniversary of mass protests that toppled Sheikh Hasina, as the interim government unveiled a road map for democratic reform with a national election next year.
Israel says it will allow gradual and controlled entry of goods to Gaza through local merchants, an Israeli military agency that coordinates aid said on Tuesday, as global monitors say famine is unfolding in the enclave, impacting the hostages Hamas holds.
Surging floodwaters and a torrent of mud swept through a village in the northern Indian Himalayan state of Uttarakhand, killing at least four people while more than 50 others were missing, authorities and local TV channels said on Tuesday.
Japan recorded its highest-ever temperature of 41.8 degrees Celsius on Tuesday, prompting the government to advise residents to stay indoors and promise steps to ease weather-related damage to rice crops.
The UAE has firmly rejected allegations from the Port Sudan Authority accusing the country of supporting armed groups in Sudan's ongoing civil conflict.