LONDON — Prime Minister Boris Johnson imposed a strict new national lockdown on Monday as Britain’s desperate race to vaccinate its population risked being overtaken by a fast-spreading variant of the coronavirus that was on track to overwhelm the nation’s beleaguered hospitals.
After several days of frighteningly high and escalating case numbers, Mr. Johnson ordered schools and colleges in England to close their doors and shift to remote learning. He appealed to Britons to stay at home for all but a few necessary purposes, including essential work and buying food and medicine.
The decision was a fresh setback for Mr. Johnson, coming at a time when the arrival of two vaccines appeared to provide a route out of the crisis after nine fraught months and fierce criticism of his handling of the pandemic.
On the day that the first doses of a vaccine developed by AstraZeneca and the University of Oxford were administered, the good news was drowned out by the reintroduction of the type of sweeping restrictions used last spring when the pandemic first threatened to run out of control.
In recent weeks, a new, highly transmissible variant of the virus has taken hold in London and southeast England, prompting an alarming spike in case numbers and putting hospitals under acute pressure.
On Sunday, Mr. Johnson admitted that the current controls on daily life were insufficient. But the first announcement of a full-scale lockdown came not from him but from Scotland, where the first minister, Nicola Sturgeon has consistently moved further and faster in efforts to try to tame the pandemic.
Speaking in Edinburgh, Ms. Sturgeon said that people in mainland Scotland would be required to stay at home and to work from there where possible, while places of worship would be closed and schools would operate largely by remote learning.
Mr. Johnson followed on Monday evening to announce the lockdown in England that many had predicted was inevitable.
“Further steps must now be taken to arrest this rise and to protect the National Health Service and save lives,” Mr. Johnson’s office said in a statement.
People in England will be encouraged to obey the new rules immediately though some of the new restrictions will be given legal force soon and there is likely to be a vote in Parliament which is being recalled specially on Wednesday.
Earlier, ministers had been celebrating the deployment of the AstraZeneca vaccine, which is not only cheaper but also much easier to store than the authorized alternative from Pfizer, saying it could turn the tide in Britain’s battle with the coronavirus.
But Britain is now involved in a high stakes race to roll out its mass vaccination program before its country’s overstretched health service is overwhelmed by the new variant. Non-Covid treatment is again being postponed and pictures of ambulances stacking up in the parking lots of some hospitals last week illustrated the challenge faced by the country’s weary health workers.
In a sign of the threat faced by hospitals, the government raised its Covid alert to its highest level for the first time, one that warned of a “material risk of health care services being overwhelmed.” On Jan. 4 there were more than 26,000 Covid-19 patients in hospitals, an increase of 30 percent from the previous week, Mr. Johnson’s office said. It added that cases were now rapidly rising across the country.
Most Britons already face strict curbs on everyday life. Nonessential stores, pubs and restaurants are already closed in much of England, where those living in the areas under the toughest rules are banned from mixing between households.
All parts of England will now be under those curbs and most schools will be closed at least until the middle of February. However, some other lockdown restrictions will be a little less onerous than those last March. People in England will still be allowed to meet one other person to exercise together outside, places of worship will remain open, as will playgrounds. Elite professional soccer matches will continue, although some matches have had to be canceled lately because of the impact of the virus.
On Sunday, after Mr. Johnson used a BBC interview to warn that new restrictions were likely, the leader of the opposition Labour Party, Keir Starmer, called for immediate new national restrictions.
But on Monday morning Mr. Johnson initially appeared to resist being forced into a quick decision, insisting, as he made a hospital visit, that the government was still measuring the impact of the toughest tier of restrictions already in place. However, he acknowledged that there were “tough” weeks to come, added that there was “no question” that harsher measures would be forthcoming and said that those would be announced “in due course.”
Even within his own Conservative Party the pressure grew too, with a senior lawmaker and former health secretary, Jeremy Hunt, writing on Twitter that it was “time to act,” and to “close schools, borders, and ban all household mixing right away.”
The essential lesson to be drawn from the handling of the pandemic was that “countries that act early and decisively save lives and get their economies back to normal fast,” he added.
Medical experts said Mr. Johnson had little choice but to impose more draconian measures, given the rapid spread of the new variant. Some said the prime minister was already behind the curve, given how the number of cases and hospital admissions had skyrocketed in the last week.
“He’s already late,” said Devi Sridhar, head of the global public health program at the University of Edinburgh. “The situation is dire with the new variant. They have to manage borders, pause schools and stop mixing between households.”
The government’s own scientific advisory panel, known as SAGE, recommended on Dec. 22 that Britain consider a national lockdown, as well as closing schools and universities, as a way to curb the new variant. It said that the variant was on its way to becoming the dominant strain of the coronavirus in many parts of the country.
New infections have surged to a rate of almost 60,000 a day, double the rate of a few weeks ago. Hospitalization rates are starting to soar as well.
Hospital admissions have doubled in London every week since the beginning of December, Christina Pagel, director of the clinical operational unit at the University College London, wrote on Twitter. With 75,024 deaths, Britain already has the highest death toll in Europe, and medical experts warn that the toll, after growing more modestly over the summer, will begin spiking again.
Others are concerned at the constant changes in messages from a government that has often appeared to be reacting to fast-moving events, rather than anticipating them.
After last year’s national lockdown the government promised to do all it could to keep schools open. But the return of students on Monday after the winter vacation was plunged into confusion as some schools in areas where infections were high were asked to close, while some head teachers decided to do so anyway.
In some cases that was because too many staff were sick, in others after reports that children could be more vulnerable to the new variant than to the original Covid-19.
One teaching union called for all primary schools to move to remote learning for the first two weeks of January except for classes that cater to vulnerable children and the families of key workers.
After days of chaos over policy toward school, Mr. Johnson on Monday reluctantly fell into line with that suggestion.