British Prime Minister Boris Johnson tests positive for coronavirus

LONDON —  British Prime Minister Boris Johnson has tested positive for the coronavirus, he announced Friday, becoming the world’s highest-profile political leader to reveal an infection.

“Over the last 24 hours I have developed mild symptoms and tested positive for coronavirus,” Johnson wrote on Twitter. “I am now self-isolating, but I will continue to lead the government’s response via video-conference as we fight this virus.”

The news comes days after the heir to the British throne, Prince Charles, also divulged that he had tested positive. The 71-year-old prince is self-isolating at a royal estate in Scotland.

Soon after Johnson’s announcement, another senior government official, Health Secretary Matt Hancock, said he, too, had tested positive for the coronavirus. Hancock has responsibility for the National Health Service.

No information was given as to how Johnson, 55, might have contracted the virus. His office said he was tested on the personal advice of Chris Whitty, the chief medical officer of England, a post equivalent to the U.S. surgeon general.

Whitty himself announced later Friday that he had begun “experiencing symptoms compatible with COVID-19” and would follow his boss in self-isolating for seven days, meaning that three of the most important officials leading the charge against the coronavirus in Britain — Johnson, Hancock and Whitty — are now afflicted with it.

Johnson is sequestering himself in the prime ministerial residence, 10 Downing St., from which he said he would continue to lead his administration and the country. “Be in no doubt that I can continue, thanks to the wizardry of modern technology, to communicate with all my top team to lead the national fightback against coronavirus,” Johnson said in a video accompanying his tweet.

Britain is under a moderate lockdown, with restaurants, pubs and other businesses shuttered and residents told to stay at home except for trips outside to buy groceries and exercise. In London, where the fine weather of the past few days would normally have sent people outdoors in droves, ordinarily bustling sidewalks and streets have been empty.

Johnson’s government has come under fire from critics who say its response to the coronavirus has been chaotic at best and dangerous at worst. As the tally of cases and deaths spiked in continental Europe, particularly in Italy and Spain, Johnson appeared to advise Britons to go about their lives as usual — in part to actually allow infections to happen and, in theory, a “herd immunity” to develop.

That approach has given way to the kind of social restrictions now seen in places such as Los Angeles and other U.S. cities. Similar warnings have also been sounded about the lack of protective gear for medical workers and possibly an unbearable strain on the NHS.

“The main stress must be on increasing testing and providing equipment,” Paul Goodman, editor of the political website Conservative Home, told the BBC. “That’s in the hands of [government] ministers, and they should carry on driving that forward anyway,” regardless of Johnson’s infection.

A spokesman for 10 Downing St. said that Johnson had begun feeling slightly ill Thursday afternoon and that his test result came back late that night.

Earlier on Thursday evening, the prime minister and Prince Charles joined residents across the country who stood at doors and windows to applaud and bang pots and pans in a coordinated show of support for the NHS, one of Britain’s most cherished institutions.

“It was very moving last night to join in that national clap,” Johnson said in his video Friday. “We will get through it, and the way we’re going to get through it is, of course, by applying the measures that you’ll have heard so much about. And the more effectively we all comply with those measures, the faster our country will come through this epidemic and the faster we’ll bounce back.”