Governments across Europe rushed on Friday to bolster their defences against a fresh coronavirus spike, as South Africa announced it had detected a new Covid-19 strain that scientists fear could torpedo efforts to beat the pandemic.
In recent weeks the continent has been in the throes of surging cases and violent riots, wrestling with booster programmes and dramatic lockdowns to stem the tide as its death toll surpassed 1.5 million and it once again became the global epicentre of an unceasing pandemic.
Scientists are now racing to understand the impact of the new, heavily mutated strain, feared to be more infectious than Delta, which brought the world back to its knees a year after the virus first surfaced in central China.
"This is the most significant variant we have encountered to date and urgent research is under way to learn more about its transmissibility, severity and vaccine-susceptibility," Britain's health agency chief Jennie Harries said in a statement.
Ahead of Thursday's announcement by scientists in South Africa, countries across Europe were already accelerating booster campaigns, enforcing stricter curbs and targeting the unvaccinated as cases multiplied to record levels.
Authorities in the Netherlands were preparing for new riots ahead of an expected announcement Friday by Prime Minister Mark Rutte to tighten a partial lockdown as it faces a critical hospital bed shortage with infections reaching record levels.
The country has suffered four straight days of anti-lockdown unrest, led by people Rutte described as "idiots", the worst in the port city of Rotterdam where police opened fire on rioters, injuring five.
"We are keeping our eyes and ears open and we are prepared," Rotterdam police spokesman Gijs van Nimwegen told AFP.
Germany, the Czech Republic and Portugal -- which has one of the world's highest vaccination rates -- all announced new measures in recent days to stem the tide of infections that has been worse than feared.
German Chancellor Angela Merkel issued an urgent warning to the country's incoming government on Thursday, saying "every day counts" as the country's death toll passed 100,000.
Europe is stepping up its vaccination drive to beat back rising cases ahead of the encroaching winter.
On Thursday, France made booster shots available to all adults and the European Union's medicines agency has approved jabs for five- to 11-year-olds.
Scientists and health officials in Britain and South Africa expressed alarm that the new variant -- expected to be code-named by the WHO on Friday -- could undo much of the hard-won gains against the virus over the summer.
The WHO said it is "closely monitoring" the reported variant and is expected to determine if it should be designated a variant of "interest" or of "concern".
Scientists have said the new B.1.1.529 variant has at least 10 mutations, compared to two for Delta or three for Beta.
"The concern is that when you have so many mutations, it can have an impact on how the virus behaves," Maria Van Kerkhove, the WHO's technical lead on Covid-19, said at a virtual press briefing.
South African Health Minister Joe Phaahla described the strain as "a major threat".
The finding has left British scientists "deeply concerned", Health Minister Sajid Javid said, because it could render current vaccines less effective.
In the first international move to protect against its spread, Britain said it would ban travel from six southern African countries.
The news of the variant's discovery spooked investors in early afternoon trade, with Tokyo stocks diving three percent.
In Asia, China's strict zero-Covid policy pushed Shanghai to cancel hundreds of flights and close some schools after three local cases were recorded, health officials said Friday.
"China has accumulated lots of experience in 'dynamic zero-Covid'," said Zhang Wenhong, head of the Shanghai Covid prevention expert task force, at a Thursday briefing.
"So our strategy won't change."
There was more positive news elsewhere, however.
The Philippines said Friday it would welcome vaccinated foreign tourists back to its shores next week from countries designated as low-risk.
But the effects of the pandemic have pushed even the most hardened skeptics on the world stage into embracing some anti-virus measures.
"As far as I'm concerned, we shouldn't have carnival" in February, said Brazilian President Jair Bolsonaro said in an interview Thursday, in a rare nod to social distancing.