LONDON – From France to Russia, from Britain to the Czech Republic, European leaders are confronting a surge in coronavirus cases that is rapidly filling hospital beds, driving up death tolls and raising the grim prospect of further lockdowns in countries already traumatized by the pandemic.

The continent, which once compared favorably to the United States in its handling of the pandemic, is being engulfed by a second wave of infection. With an average of more than 100,000 new infections per day over the past week, Europe now accounts for about one-third of new cases reported worldwide.

In the most vivid sign of the deteriorating situation, President Emmanuel Macron of France on Wednesday imposed a curfew of 9 p.m. to 6 a.m. in the Paris region and eight other metropolitan areas, beginning Saturday. “The virus is everywhere in France,” he told the French public as he declared a state of emergency.

The resurgence has prompted officials to close bars and clubs in Prague and Liverpool, England, and to make face masks mandatory in public indoor spaces in Amsterdam. In Russia, which reported its largest daily increase in infections Wednesday, President Vladimir Putin sought refuge from the torrent of bad news by announcing that his government had approved a second vaccine.

Chancellor Angela Merkel of Germany better captured the anxious mood when she said Tuesday, “I am watching with great concern the renewed increase in infection numbers in almost every part of Europe.” Merkel added, “We mustn’t throw away what we achieved via restrictions over the past months.”

To some extent, Europe’s setback is hardly a surprise. Public health experts have long warned that the virus could roar back when the days grew colder, driving people indoors, where the risk of transmission is far greater.

In several European countries, lockdowns were lifted abruptly, sowing complacency among people who felt they could return to their normal lives. In the face of intense political pressures, European leaders have been reluctant to impose new, economically damaging lockdowns, often opting for the lightest possible measures.

For Germany and a handful of its neighbors, this second wave is particularly demoralizing because they had navigated the first wave relatively well. In late June, revelers in Prague celebrated the end of the outbreak with a dinner party stretching across the Charles Bridge. Spain and Italy, which were hard hit in March and April, threw open their doors to vacationers in July and August.

Now, with these countries experiencing an alarming spread of the virus, the carefree days of summer are a distant memory.

On Wednesday, Merkel and Macron announced a raft of nationwide restrictions in their countries, ranging from the closing of bars and restaurants to the mandatory use of masks. The curfews in Paris and other French cities, including Lyon, Toulouse and Marseille, will last at least four weeks.

“We haven’t lost control,” Macron insisted. “We are in a situation that is worrying that justifies being neither inactive nor panicked.”

Germany reported 5,132 new infections Tuesday, up from 2,639 a week earlier; France reported 120,000 new cases over the past seven days, one of the highest rates in the world.

French officials warned that in the Paris region, intensive care units would be 70% to 90% filled with COVID-19 patients by the end of the month. The surge in cases has thrown into disarray Macron’s plan to shift his focus to economic recovery, with a fiscal stimulus plan worth 100 billion euros ($117 billion).

“All of the government’s strategy is destabilized,” said Jérôme Fourquet, a political analyst at the IFOP polling institute. Macron’s ambitions, he said, were “colliding with the necessity to put out the fire, from a health standpoint.”

In the Spanish region of Catalonia, where cases have risen 40% in the past week, authorities closed bars and restaurants for 15 days, except for takeout food. Shops were told to limit their traffic to 30% of capacity.

“We are in an extremely complicated situation,” the acting regional leader of Catalonia, Pere Aragonès, said on Twitter.

In Britain, which has suffered the greatest number of virus deaths in Europe, Prime Minister Boris Johnson has walked a tightrope between scientific advisers who are pushing for another nationwide lockdown and members of his Conservative Party who warn that such a draconian response would wreck the economy.

On Monday, Johnson rolled out a three-tier system of restrictions. Though the government initially put only put hard-hit Liverpool in the highest-level tier, other cities, like Manchester, are likely to be added soon.

Among European countries, only Russia has put the emphasis on positive developments. But its new vaccine has yet to complete critical, late-stage clinical trials to determine safety and effectiveness.

Tatiana Golikova, a deputy prime minister coordinating Russia’s response to the pandemic, said the new vaccine had so far been tested on only 100 volunteers. Golikova, who said she had been injected herself and “did not feel any complications,” added that trials would now be carried out across the country with 40,000 volunteers.

News of the vaccine led news reports on state-controlled television, obscuring news earlier in the day that Russia had recorded 14,231 new infections, the biggest daily increase since the pandemic began.