Flight crew members wearing face masks to prevent the spread of coronavirus walk along the Adolfo Suarez-Barajas international airport in Madrid, Spain, Thursday, Dec. 2, 2021. The coronavirus's omicron variant kept a jittery world off-kilter as reports of infections linked to the mutant strain cropped up in more parts of the globe. (AP Photo/Manu Fernandez)

Swiss health authorities have ordered the entire student body and staff of a branch of a renowned international school – some 2,000 people – to go into quarantine for 10 days after two confirmed cases of the omicron variant turned up on campus.

The Ecole Internationale campus known as La Chataigneraie, in suburban Geneva, was ordered shut by regional health authorities in the Vaud region starting Thursday evening, according to a notice sent to parents obtained by The Associated Press.

The quarantine order applies to all people, including those who have been vaccinated, and all students and staff are to take a PCR test in about five to seven days, according to the notice. It says family members will be required to take a PCR test.

The Associated Press contributed to this report.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, speaks during the daily briefing at the White House in Washington, Wednesday, Dec. 1, 2021. (AP Photo/Susan Walsh)

Dr. Anthony Fauci on Wednesday advised viewers of a CNN town hall to wear a mask indoors even if they've been fully vaccinated against the coronavirus and received the vaccine booster. 

While virtually participating in the town hall focused on the pandemic, Fauci told the audience, in contrast to CDC mask guidance, to wear a mask while congregating with people indoors if they are unsure of everyone else's vaccination status. 

"Everyone’s been talking about what to do if you’re unvaccinated or without a booster, but what should someone who has all three shots do to protect themselves against the omicron variant?" a member of the virtual audience asked Fauci.

"Yeah, good question. We’re asking people to go get booster shots and the question that was just asked is very relevant. What you do is exactly what we were saying, and that is to be prudent and careful," Fauci said. 

"And one of the things that’s very clear is that if you have to be in an indoor congregate setting in which you’re unsure of what the vaccination status is of the people around you, wear a mask," he said. 

Fauci added that it was important to have good ventilation while indoors and that, even though the country was heading into colder months, to try and hold gatherings with large groups of people outdoors.

"It’s just the common sense, prudent, trying to avoid a risky situation. But you’ve already taken a major step in protecting yourself by the fact that you have gotten vaccinated and you have gotten boosted. That’s a real big step towards protecting yourself," Fauci said. 

Fox News' Brandon Gillespie contributed to this report.

Minnesota Governor Tim Walz speaks in St. Paul, Minnesota, U.S. April 20, 2021 after the verdicts in the trial of Derek Chauvin, the former Minneapolis policeman found guilty of killing George Floyd, a Black man, in Minneapolis. (REUTERS/Eric Miller)

The Minnesota Department of Health said Thursday that lab testing had confirmed the state’s first omicron COVID-19 case.

In a news bulletin, the department said that the infected Minnesota resident had recently returned from domestic travel and that the variant had been detected through its variant surveillance program.

The individual is an adult male and a resident of Hennepin County. He was vaccinated against COVID-19.

The man developed mild symptoms on Nov. 22, 2021, and sought COVID-19 testing on Nov. 24, 2021. Those symptoms have since resolved.

"The Minnesota Department of Health (MDH) today announced that its Public Health Laboratory has found the variant of the SARS-CoV-2 virus known as Omicron in a specimen from a Minnesota resident with recent travel history to New York City," the department wrote.

The individual told investigators that he had attended the Anime NYC 2021 convention at the Javits Center from Nov. 19-21, 2021.

He was advised to isolate from others.

“Since the beginning of this pandemic, Minnesota’s nation-leading genome sequencing infrastructure and strong testing network have allowed the state to quickly track the COVID-19 virus and better understand its spread. Today, those tools detected a case of the Omicron variant in Minnesota,” Governor Tim Walz said in an accompanying statement. “This news is concerning, but it is not a surprise. We know that this virus is highly infectious and moves quickly throughout the world. Minnesotans know what to do to keep each other safe now — get the vaccine, get tested, wear a mask indoors, and get a booster. Together, we can fight this virus and help keep Minnesotans safe.”

Walz also tweeted Thursday that the news had been "concerning," but was "not a surprise."

"We know that this virus is highly infectious and moves quickly throughout the world," he said.

Minnesota Commissioner of Health Jan Malcolm said the finding underscores the importance of continued efforts by Minnesotans to limit the spread of COVID-19 in any form.

“We still have more to learn about Omicron, but the most important thing we can do right now is to use the tools we have available to make it as hard as possible for this virus to spread,” Malcolm said. “In addition to vaccination and boosters, we can slow the spread of this variant and all COVID-19 variants by using the tried-and-true prevention methods of wearing masks, staying home when sick, and getting tested when appropriate.”

The department added that Minnesota epidemiologists will continue to investigate in collaboration with New York City and the U.S. Centers for Disease Control and Prevention (CDC).

Speaking to reporters, New York Gov. Kathy Hochul said Thursday that there are no confirmed cases of omicron in the Empire State, but warned residents to be prepared and not pandemic. 

She encouraged people to get booster shots and wear masks. 

"We are ready unlike in March 2020…" said Hochul.

“We are aware of a case of the Omicron variant identified in Minnesota that is associated with travel to a conference in New York City, and we should assume there is community spread of the variant in our city. We are working closely with the State and the CDC, as well as the Javits Center’s event organizers, and our Test and Trace Corps will be contacting conference attendees. This conference required masks and complied with our Key2NYC requirement to mandate vaccination," New York City Mayor Bill de Blasio said in a statement. 

The mayor urged anyone who had attended the AnimeNYC conference – and especially anyone experiencing COVID-19 symptoms – to “get tested immediately and take additional precautions, including social distancing.”

“I urge all New Yorkers to get vaccinated, wear a face mask while indoors and in public, and help our city beat this virus once and for all,” he said.

White House Press Secretary Jen Psaki told reporters on Thursday the department will hold a press conference a noon EST with additional information.

Psaki said there were no other omicron variant-linked cases in the U.S. at the moment that she was aware of.

"I would note, as Dr. Fauci has said over the course of the last week every single day, we do – even the restrictions we put in place [were] not going to prevent this variant from coming here. It would just slow. That was the objective," she said. "So, we do anticipate there will be more cases and we know that will be the case and that's why we're focused on doing everything we can to fight the virus and the variant."

Psaki pointed out that scientists are still determining whether omicron is less or more deadly than other variants.

In a statement shortly after her remarks, the CDC said it was working with the Minnesota Department of Health and the New York City Department of Health and Mental Hygiene to investigate the case.

“CDC has been actively monitoring and preparing for this variant. We have been working closely with Minnesota’s Department of Health and will continue to work diligently with other U.S. and global public health and industry partners as we learn more," CDC Director Dr. Rochelle Walensky said. "CDC has expanded its capacity for genomic sequencing over the past nine months and we have more tools to fight the variant than we had at this time last year from vaccines to boosters to the prevention strategies that we know work including masking in indoor public settings, washing your hands frequently and physical distancing. These methods work to prevent the spread of COVID-19, no matter the genetic sequence.”

The agency recommends that people follow COVID-19 prevention strategies.

White House COVID-19 Response Coordinator Jeffrey Zients (Credit: AP)

White House COVID-19 Response Coordinator Jeffrey Zients told MSNBC's "Morning Joe" on Thursday that the Biden administration would "pull out all the stops to prepare for the winter" and the omicron variant.

Zients touted the president's "robust" winter COVID-19 booster and testing campaign, which was unveiled Thursday and includes a requirement for private insurers to cover the cost of at-home COVID-19 tests and a tightening of testing requirements for people entering the U.S. regardless of their vaccination status. 

"Most importantly, the president is announcing a national campaign to boost the 100 million Americans who are now eligible for a booster and haven't yet gotten their booster. This is really important because boosters provide the highest level of protection against COVID," Zients said, echoing comments he made earlier on CBS "This Morning."

Zients said the president was also announcing hundreds of new family vaccination sites and that it was "really important" the administration implements existing vaccine mandates.

Next, referencing recent travel restrictions enacted due to the omicron variant, Zients said Biden would announce stricter international travel and mask requirements.

"Starting early this month, we put in place a vaccination requirement for all foreign nationals traveling to the to the U.S., and now we're tightening the testing requirements for all," he said. "Testing has to be done within 24 hours of departure. And, as I mentioned, extending the mask mandate for all domestic and international travel."

When it comes to a vaccine requirement for domestic travel, however, Zients said the administration was focused on implementing workplace vaccine requirement.

The Associated Press contributed to this report.

In this May 25, 2016, file photo, bins containing bags needing additional screening are automatically separated on a conveyer belt at a newly designed passenger screening lane unveiled at Hartsfield-Jackson Atlanta International Airport in Atlanta. (AP Photo/David Goldman, File)

The Transportation Security Administration (TSA) said Thursday that, following President Biden's order and announcement regarding efforts to combat the omicron variant, it would extend the face mask requirement for individuals across all transportation networks throughout the U.S.

"Following the President’s order and announcement regarding efforts to combat the omicron variant, TSA, in conjunction with the CDC, will extend the face mask requirement for individuals across all transportation networks throughout the United States, including at airports, onboard commercial aircraft, on over-the-road buses, and on commuter bus and rail systems through March 18, 2022," the agency said.

"TSA Administrator David Pekoske has said frequently the combination of vaccinations and face masks work and are highly effective in terms of slowing the spread of the virus in the transportation system, and they make travel safer for everyone," it added.

The TSA said more details about the extension would be available "soon."

President Joe Biden speaks in the South Court Auditorium on the White House campus, Wednesday, Dec. 1, 2021, in Washington. Biden is set to kick of more urgent campaign for Americans to get COVID-19 booster shots on Dec. 2, as he unveils a his winter plans to combat the coronavirus. (AP Photo/Evan Vucci)

President Biden is set to announce that health insurers must cover 100% of the cost of in-home COVID-19 tests as part of his winter plan to combat the pandemic.

"The President will announce his health insurance must cover 100% of the cost of at-home tests purchased by their members," a senior administration official said of the president's planned announcement.

The move will come as part of Biden's winter plan to combat COVID-19 as fears grow over the spread of the Omicron variant, with U.S. recording its first case of the new strain Wednesday.

Other measures the president plans to announce Thursday include increased access to vaccine boosters, launching more family vaccination clinics in an effort to get more kids vaccinated, distributing 50 million free tests throughout the country, and a requirement that all international travelers show a negative test one day being departure. 

"We will continue to act aggressively, we will continue to follow the science, we will continue to prepare for all scenarios and work day and night to protect the American people, keep our schools open, keep our economy growing and get this pandemic behind us," a senior administration official said.

Biden will also call on businesses to voluntarily implement a vaccine mandate as part of his announcement.

"What we’re doing is what we’ve done all along, which is we’re asking businesses to step forward and do the right thing to protect our workers, protect our community and to put in place some sort of vaccination requirement or testing requirements for the workplace," a senior administration official said. "We know they work and we think it’s in the best interest of public health."

Left out are some of the more controversial proposals the White House was reportedly considering, including a requirement that all travelers quarantine for seven days after arriving in the country even if they receive a negative test, a rule that would have also applied to U.S. citizens. A failure to comply with the rule would have resulted in fines and penalties.

Fox News' Michael Lee contributed to this report.

Albert Bourla, Pfizer CEO, during a U.S. Senate Finance Committee hearing on drug prices. Credit: AP

Pfizer CEO Albert Bourla told the BBC on Thursday that people will likely need annual vaccinations against coronavirus for many years to come to maintain a "very high level of protection."

The outlet reported that the vaccine maker is currently conducting trials in children under five years old, noting that the U.S. Food and Drug Administration (FDA) had approved the Pfizer vaccine for kids aged 5-11 in the fall.

Bourla reportedly said that immunizing that same age group in the United Kingdom (U.K.) and Europe would be a very good idea.

"COVID in schools is thriving," he pointed out.

"This is disturbing, significantly, the educational system, and there are kids that will have severe symptoms, Bourla continued.

"So there is no doubt in my mind that the benefits, completely, are in favor of doing it," he said.

The virus has been surging in Europe as the weather has turned colder and fear surrounding the omicron variant has led to new restrictions.

The BBC highlighted that Pfizer and Moderna's mRNA vaccines had "taken over almost completely" from the U.K.'s Oxford-AstraZeneca shot.

Additionally, on Thursday, the European Union (EU) drug regulator announced it has started a rolling review of a new vaccine made by French startup Valneva.

Approval by the European Medicines Agency would add another vaccine to the EU’s armory against the disease, as the bloc ramps up administering booster shots and some countries are preparing to deliver shots of Pfizer’s vaccine to children ages 5 to 11.

The Associated Press contributed to this report.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, speaks during the daily briefing at the White House in Washington, Wednesday, Dec. 1, 2021. (AP Photo/Susan Walsh)

The U.S. Centers for Disease Control and Prevention has identified the first case of the omicron COVID-19 variant in the U.S.

"The California and San Francisco Departments of Public Health have confirmed that a recent case of COVID-19 among an individual in California was caused by the Omicron variant (B.1.1.529)," the CDC wrote in a Wednesday statement.

The agency explained that the individual was a traveler who returned from South Africa on Nov. 22, 2021.

"The individual, who was fully vaccinated and had mild symptoms that are improving, is self-quarantining and has been since testing positive. All close contacts have been contacted and have tested negative," the CDC noted.

Genomic sequencing was conducted at the University of California, San Francisco and the sequence was confirmed at CDC as being consistent with the "variant of concern."

Dr. Anthony Fauci, White House chief medical adviser, told reporters in a news conference that the individual had tested positive on Nov. 29, 2021 and had not received a booster shot.

He said that officials "knew it was just a matter of time before the first case of omicron would be detected in the U.S."

"We know what we need to do to protect people. Get vaccinated, if you're not already vaccinated. Get boosted if you've been vaccinated for more than six months with an mRNA or two months with [Johnson & Johnson] and all the other things we've been talking about..." Fauci said, adding later that there are currently no other cases the CDC is investigating as omicron-linked.

"As the president said last Friday, it was only a matter of time before the first case of omicron was detected in the U.S.," the White House said in a statement later in the day. "We are prepared to meet this challenge with science and speed."

"The president's medical team continues to believe that existing vaccines will provide some level of protection against severe illness from omicron and individuals who have gotten boosters have even stronger protection," they continued. "As such, we urge all adults to get their booster shots and to get themselves and their kids vaccinated, if they haven't already."

The news comes as scientists continue to study the risks posed by the new strain of the virus.The Biden administration moved late last month to restrict travel from Southern Africa where the variant was first identified and had been widespread. Clusters of cases have also been identified in about two dozen other nations.

The CDC was moving to tighten U.S. testing rules for travelers from overseas, including requiring a test for all travelers within a day of boarding a flight to the U.S. regardless of vaccination status. It was also considering mandating post-arrival testing.Officials said those measures would only “buy time” for the country to learn more about the new variant and to take appropriate precautions, but that given its transmissibility its arrival in the U.S. was inevitable.

Fox News' Julia Musto and the Associated Press contributed to this report