Germany, Sweden, Portugal and Scotland on Tuesday ordered tighter restrictions on gatherings as the omicron variant continued its march across Europe, and Swedish officials warned that a surge of infections driven by the variant would continue rising until mid-January.

Sweden’s public health agency also released new forecasts that suggested that, under a worst-case scenario, in which vaccinations afford the least protection against being infected with omicron, the country could see 15,000 daily infections in mid-January, far higher than previous peaks.

In Germany, state governors and Chancellor Olaf Scholz met to discuss, among other things, keeping critical infrastructure — including police, firefighters and medical services — functioning in the face of a likely omicron surge.

Sweden’s new rules include a cap of 50 people for private gatherings and instructions that most people should work from home. In announcing them, Prime Minister Magdalena Andersson said that the country, which had thrown off nearly all restrictions over the summer, “must adapt to the new reality.”

“I understand that many are tired of this — so am I — but we now have a new virus variant, which means we are in a new situation,” she said.

Days before Christmas, many European nations are imposing new social restrictions, mask mandates and travel rules as omicron drives the Continent’s infection rates to their highest levels of the pandemic. An average of 51 daily cases per 100,000 people is being recorded in Europe, the most of any continent.

Denmark announced Tuesday that it had recorded 13,558 cases in the previous 24 hours, a daily record. The health minister, Magnus Heunicke, said on Twitter that omicron was now the dominant variant in the country “and continues to grow.”

The government of Portugal said Tuesday that it was reintroducing of a raft of lockdown restrictions to respond to another surge in coronavirus cases, almost half of which are now of the omicron variant.

The measures include the closure of all nightclubs and the obligation to work from home. Residents will also have to present a negative test result to enter establishments like theaters and sports venues, while such a test result will also have to be shown to enter a restaurant on the special days of the winter holiday season, including Christmas and New Year’s Eve.

The government said the measures would come into force Saturday. Portugal is facing a rise in cases even as it is among the countries that has the most advanced vaccination rollout, with 87% of its population vaccinated to date.

Scotland announced limits on crowds at large events for three weeks, beginning the day after Christmas, and ordered bars and restaurants only to serve seated patrons in order to limit social contact. The rules in effect mean that professional sporting events will take place without spectators, following a similar announcement made by the government of Wales.

“The obligation of government is to take difficult decisions to keep the country as safe as possible, no matter how unpopular they might be,” said Scotland’s first minister, Nicola Sturgeon.

Omicron is now the dominant variant in Scotland, just as it is in London, the epicenter of the virus surge in Britain, where daily case totals have set records.

German authorities agreed to ban gatherings bigger than 10 — whether indoors or outdoors — as well as reducing audiences for sports and cultural events and closing all clubs and discothèques.

Other rules, such as restrictions keeping unvaccinated people out of all but the most essential businesses, will remain in place. The daily number of infections in Germany has been decreasing in recent days, as the country is overcoming the worst of its fourth pandemic wave.

“This pandemic is wearing us all out,” Scholz said at a news conference after his meeting with the governors. “We are all worn down and tired of the pandemic. But that can’t be helped. Once again, we have to stand together and, in many cases, keep our distance.”

Noting that last Christmas and Easter did not really increase infections, Scholz said the measures would only go into effect after Christmas, but asked people to have themselves tested before meeting loved ones.

Also Tuesday, the European Union said that from next year, people would be allowed to travel freely within the bloc only if they had received booster shots or had been fully vaccinated within the previous nine months.

The new rules, which are set to come into force Feb. 1, aim to standardize travel across the bloc by setting an expiration date on COVID-19 passes, which first came into effect in July and show the holders’ vaccination status. But even with the rules, individual countries can still decide whether to require visitors to quarantine or show proof of a negative test upon entry. The change also does not affect domestic passes that some countries require for entry into public places like bars and restaurants.

This article originally appeared in The New York Times.

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