LONDON — Prime Minister Boris Johnson of Britain was discharged from the hospital on Sunday, a major step forward in his recovery from the coronavirus and a welcome relief for a nation whose political leadership has been harder hit by the contagion than that of any other Western country.
Mr. Johnson, who spent three nights in intensive care at St. Thomas’ Hospital in London, will convalesce for some time at Chequers, the prime minister’s country house, the government said in a statement. But he will soon be able to sign off on major decisions, including when to ease the country’s lockdown.
In an emotional five-minute video, Mr. Johnson thanked the country’s National Health Service, declaring it had “saved my life, no question.”
Wearing a suit and tie, but looking and sounding fatigued, Mr. Johnson singled out two nurses from New Zealand and Portugal who, he said, had kept a vigil over him “when things could have gone either way.”
“The reason in the end my body did start to get enough oxygen was because for every second of the night they were watching and they were thinking and they were caring and making the interventions I needed,” Mr. Johnson said.
As he did when he first announced he had contracted the virus two weeks ago, the prime minister sought to draw a broader lesson from his own ordeal — in this case, that the country’s strict lockdown was enabling the National Health Service to perform as heroically for all Britons as it had for him.
Mr. Johnson said nothing about his own plans for recuperation, but Downing Street said in a statement, “On the advice of his medical team, the P.M. will not be immediately returning to work.”
Now, those fears have subsided, though it may still be weeks before Mr. Johnson retakes his place at the center of British politics. Full recovery from a serious case of the virus is lengthy and arduous, medical experts say, and Mr. Johnson’s family has warned that he should not return to work too soon.
“He has to take time,” his father, Stanley Johnson, told BBC Radio on Friday. “I cannot believe you can walk away from this and get straight back to Downing Street and pick up the reins without a period of readjustment.”
Britain is still in a desperate phase of its battle with the pandemic. The death toll topped 10,000 on Sunday, and experts warned that the peak of the outbreak was still to come. Hospitals, though badly stretched and suffering an acute shortage of protective gear, have coped with the surge of patients.
Britain is also struggling to ramp up its testing after a slow start amid internal debates over how aggressively to try to curb the spread of the virus. It has set an ambitious goal of testing 100,000 people a day by the end of April.
Mr. Raab said the government would not lift the lockdown on Monday, the date Mr. Johnson set on March 23 to review the restrictions. As in other countries, British officials are engaged in a vexing debate over reopening the economy, and risking new outbreaks, or leaving it closed, and causing lasting damage.
While Mr. Johnson will not attend those meetings, he will most likely play an influential role in that decision.
The prime minister said on March 27 that he had tested positive for the virus, but continued to work, taking part in daily meetings about the pandemic by video while in isolation in his apartment next door to 10 Downing Street.
Officials initially said they expected him to come out of isolation after a week. But Mr. Johnson continued to suffer a cough and high temperature, and his condition worsened until the evening of April 5, when he was moved to St. Thomas’, across the Thames River from Parliament.
His hospitalization was announced about an hour after a rare address to the nation by Queen Elizabeth II, a juxtaposition that left many in the country unsettled.
The government offered reassuring, if unrevealing, updates about Mr. Johnson, who was invariably described as being in “good spirits.” But top officials, including Mr. Raab, conceded that they had not spoken to the prime minister since before he was admitted to the hospital, sowing doubts about his condition.
Then, on April 6, the prime minister was moved into the intensive care unit and given oxygen treatment. The government said Mr. Johnson did not require a ventilator, a development that typically reduces the chances of survival. But his sudden deterioration alarmed colleagues and members of his family, and his own description of his experience suggests his condition was far more perilous than the reports indicated.
“There were times last week that were very dark indeed,” Mr. Johnson’s girlfriend, Carrie Symonds, said on Twitter on Sunday after his release. “My heart goes out to all those in similar situations, worried sick about their loved ones.”
Ms. Symonds, 32, is herself recovering from symptoms of the virus. She is pregnant, and the couple have announced plans to get married.
Three days after entering intensive care, Mr. Johnson had improved enough to be transferred to a ward, where officials said he was sitting up and even taking short walks.
While in hospital, Mr. Johnson was reported to have been watching movies that his Downing Street staff had put on a disc for him. One of them was “Love Actually,” the 2003 romantic comedy that he appropriated for a campaign advertisement during last year’s election, when he was filmed turning up on a doorstep to plead for a woman’s vote with flashcards. Mr. Johnson acknowledged he had never watched the film.
In his video, Mr. Johnson sounded a bit stunned by what he had just gone through. He called the virus, “a fight we never picked against an enemy we still don’t entirely understand.”
But in keeping with his role as the chief messenger of the government’s slogan “Stay Home. Protect the N.H.S. Save Lives,” Mr. Johnson kept his focus on his firsthand exposure to the pressures facing the National Health Service.
Mr. Johnson lavished praise on the doctors had treated him, “several of them for some reason called Nick,” he said, “who took some crucial decisions a few days ago for which I will be grateful for the rest of my life.”
He saved his most personal words for the rotating staff of nurses, naming nearly a dozen and singling out “Jenny from New Zealand” and “Luis from Portugal,” who were at his bedside during the frightening overnight hours.
“Across this country, 24 hours a day, for every second of every hour,” he said, “there are hundreds of thousands of N.H.S. staff who are acting with the same care and thought and precision as Jenny and Luis.”