Japan has confirmed its first case of the new Omicron COVID-19 variant as countries around the world continue to tighten and close borders to try to keep the strain at bay.
Japan's first case of the variant is a man in his 30s who arrived from Namibia on Sunday.
It has been revealed after Japan announced on Monday it would ban all foreign visitors beginning Tuesday as an emergency precaution against the variant.
The World Health Organisation warned on Monday the global risk from the Omicron variant is "very high" based on the early evidence, saying it could lead to surges with "severe consequences".
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Other countries are also rushing to take measures to protect against the strain.
Switzerland will require travellers from Portugal, Nigeria, Canada and Japan to quarantine for 10 days from midnight tonight local time, due to the presence of the variant in those countries.
Travellers from those countries will also require a negative test before boarding flights to Switzerland.
Meanwhile, Chile will close its borders to non-resident foreigners who have been to any of seven specified southern African nations in the last 14 days.
Those countries are South Africa, Zimbabwe, Namibia, Botswana, Lesotho, Eswatini and Mozambique.
The border restrictions will serve as prevention against the omicron variant of coronavirus, identified for the first time in South Africa, said the undersecretary of Healthcare Networks, Alberto Dougnac.
In Germany, chancellor Angela Merkel will hold talks with the governors of the country's 16 states today amid growing concerns about the steep rise in new COVID-19 cases in the country.
A third case of the Omicron variant was detected on the weekend in the central German state of Hesse. The previous two were detected in Munich, Bavaria.
READ MORE: What we know about Omicron, the new COVID-19 variant
Canada has now confirmed at least three cases of the Omicron variant, and health officials in several provinces said "dozens" more cases are under investigation.
More than a hundred travellers from southern African countries were asked to take a new COVID-19 test and isolate, Quebec's health minister Christian Dubé said.
Mr Dubé also suggested that Nigeria should possibly be added to the list of countries currently included in a travel ban to Canada.
Japan announced it would bar entry of all foreign visitors, while new cases of the variant identified days ago by researchers in South Africa appeared in places such as Hong Kong and Australia.
New cases in Portugal and Scotland might already point toward local spread of the variant outside of southern Africa.
"There might already be some community transmission of this variant in Scotland," First Minister Nicola Sturgeon said after Scotland reported its first six cases.
The infections showed the near impossibility of keeping the genie in the bottle in a globalised world of travel and open borders.
Yet, many tried to do just that, even against the urging of the World Health Organisation, which noted that border closings often have limited effect and can wreak havoc on lives and livelihoods.
Some argued that such restrictions could provide valuable time to analyse the new variant. Little is known about it, including whether it is more contagious, more likely to cause serious illness or more able to evade the protection of vaccines.
Praise for Botswana, South Africa
The WHO warned, however, that "the likelihood of potential further spread of Omicron at the global level is high. Depending on these characteristics, there could be future surges of COVID‐19, which could have severe consequences."
While the initial global response to COVID-19 was criticised as slow and haphazard, the reaction to the new variant came quickly.
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"This time the world showed it is learning," said European Union Commission President Ursula von der Leyen, singling out South African President Cyril Ramaphosa for praise. "South Africa's analytic work and transparency and sharing its results was indispensable in allowing a swift global response. It no doubt saved many lives."
The WHO has praised Botswana as well as South Africa for quickly alerting the world to the presence of the new variant — and many have warned the countries should not be punished for their speed.
But that did not hold von der Leyen back from pushing the 27-nation EU toward imposing an immediate ban on flights from seven southern African nations — similar to measures many countries have taken.
Cases had already been reported in Belgium, Denmark and the Netherlands before Portuguese authorities identified 13 cases of Omicron among team members of the Belenenses professional football club. Authorities reported that one member recently traveled to South Africa. Its game against Benfica over the weekend had be abandoned at halftime for lack of players.
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Quarantining also became an issue when Dutch military police had to arrest a husband and wife who left a hotel where they were being held after testing positive and boarded a plane bound for Spain.
"Quarantine is not obligatory, but we assume people will act responsibly," spokeswoman Petra Faber said.
Japan shuts borders without any cases
Taking no chances, Japan, which has yet to detect any Omicron cases, reimposed border controls that it eased earlier this month for short-term business visitors, foreign students and workers.
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"We are taking the step as an emergency precaution to prevent a worst-case scenario in Japan," Prime Minister Fumio Kishida said. The new measures begin Tuesday.
Israel likewise decided to bar entry to foreigners, and Morocco said it would suspend all incoming flights for two weeks starting Monday.
Despite the global worry, scientists cautioned that it is still unclear whether Omicron is more alarming than other versions of the virus that has killed more than 5 million people.
And in some parts of the world, authorities were moving in the opposite direction.
In Malaysia, officials went ahead with the partial reopening of a bridge connecting it to the city-state of Singapore. And New Zealand announced it will press ahead with plans to reopen internally after months of shutdown, though it is also restricting travel from nine southern African nations.
Prime Minister Jacinda Ardern said that she didn't anticipate any further restrictions and that bars, restaurants and gyms in Auckland can reopen, ending a coronavirus lockdown that began in August.
"We've come through the past two years of COVID in better shape than nearly anywhere in the world," Ardern said, pointing to low death rates, a growing economy and high vaccination rates.
READ MORE: What we don't know about the Omicron variant
Dr Francis Collins, director of the National Institutes of Health in the United States, meanwhile, said no data as yet suggests the new variant causes more serious illness than previous versions.
Collins echoed several experts in saying the news should make everyone redouble their efforts to use the tools the world already has, including vaccinations, booster shots and measures such as mask-wearing.
The US is banning travel from South Africa and seven other southern African countries starting Monday. "It's going to give us a period of time to enhance our preparedness," the United States' top infectious disease expert, Dr Anthony Fauci, said on ABC's This Week.
Fauci said it will take approximately two more weeks to have more definitive information on the transmissibility, severity and other characteristics of Omicron, according to the White House.
