The World Health Organization in Europe has said it was seeing an "explosion" of coronavirus cases in the region and warned of a "tough time" ahead as mortality rates rose.
"We do see an explosion.... in the sense it only takes a couple of days to have over the European region an increase of one million cases," WHO's regional director for Europe Hans Kluge told AFP.
Mr Kluge, who was wearing a mask even as he was interviewed over a webcam meeting, also said the mortality rate could be seen rising "little by little".
"It's going to be a little bit of a tough time, we need to be honest on that," he said.
In spite of the rapidly rising cases, Mr Kluge cautioned that closing schools should be seen as a last resort, especially in light of there being "no reasons to say that schools are a main driver of the transmission".
"We need to keep the schools open really until last because we cannot afford a Covid-19 lost generation," Mr Kluge said.
However the regional director also said that the "status quo is not an option" and called for "proportionate targeted measures," which could be scaled up.
Mr Kluge stressed that governments should take into account two things: "coherence, so people see that we don't flip-flop, and... predictability, so people know if this threshold is being reached, this is what is going to happen."
He also called for the widespread use of face masks.
"With general mask wearing and strict control of social gatherings we can save 266,000 lives by February in the whole European region," Mr Kluge said.
WHO Europe spans 53 countries, including Russia and countries in Central Asia, and today reported a total of over 12 million cases in the region, with nearly two million in the last seven days.
While managing the Covid-19 pandemic was the immediate concern, Mr Kluge also said there were lessons to learn in case an even more dangerous virus were to appear.
"Imagine that Covid was as easily transmitted as measles, or imagine that Covid was as lethal as Ebola... We need to take this chance to be better prepared for the future," Mr Kluge said.
England's 56 million people re-entered a lockdown today, after crowds queued outside soon-to-close shops, booked a last-minute haircut or headed to the pub for a final pint.
Some late-night revellers clashed with police, including in parts of London and the northern city of Leeds, as scepticism mounts about the return to stringent curbs.
The new restrictions are planned to run until 2 December and mandate a return to working from home where possible, along with the closure of all non-essential shops and services, while schools will stay open.
"For us, it's absolutely insane," Faraj Faraj, head of operations at the London food market Mercato Metropolitano, told AFP.
"To go through this again, just before Christmas, is actually death by a thousand cuts."
To try to soften the blow, finance minister Rishi Sunak announced Britain will continue to pay up to 80% of wages for private sector workers until the end of March.
Britain is among the world's hardest-hit countries with just over one million virus cases and nearly 48,000 deaths.
Denmark announced it would cull its entire population of more than 15 million minks after a mutation of the new coronavirus was found to have spread to people from the otter-like mammals.
Prime Minister Mette Frederiksen, whose nation is the world's largest exporter of mink fur, said the discovery could threaten the effectiveness of any future Covid-19 vaccine.
France, meanwhile, locked down last week in the face of soaring infections, but the mayor of Paris announced today that stores selling alcohol and food to late-night shoppers will be forced to close at 10pm to "avoid gatherings".
In Italy, shops selling non-essential goods will be shut from tomorrow in hard-hit "red zone" areas and people largely confined to their homes except for work, health and emergencies.
Authorities have also announced a nationwide nighttime curfew despite growing anger in some regions which suspect other areas are getting off lightly.
"It's a slap in the face for Lombardy," raged the northern region's president Attilio Fontana, a member of the far-right opposition League party.
Greece announced it will re-enter a three-week lockdown from Saturday, with Prime Minister Kyriakos Mitsotakis saying "it was a difficult decision", but that something had to be done.
In Sweden - which has famously refused the mandatory lockdowns seen elsewhere in Europe - Prime Minister Stefan Lofven said he had gone into self-isolation after being in the "vicinity" of someone with Covid-19.
"More people are infected. More people are dying. It is a serious situation," he said today as Sweden's total death toll passed 6,000.
In the Netherlands, museums, cinemas, theatres, zoos and amusement parks were closed from 10pm yesterday for at least two weeks.
Russia officially has no plans for a lockdown but that resolve may be tested after yesterday saw record daily infections of nearly 20,000 and a death toll of nearly 400.
The second wave has also stalled a nascent economic recovery in Europe, with the EU warning it will not return to normality before 2023.
"The rebound has been interrupted," European Union's economic affairs commissioner Paolo Gentiloni said as he unveiled a grim economic outlook.
The United States meanwhile recorded its worst ever daily caseload - 99,660, according to Johns Hopkins University - as the winner of the presidential election was still being determined in a country which has suffered a global record of 233,000 Covid-19 deaths.