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As news of a spreading COVID-19 variant of concern emerged Friday, the United States’ top infectious disease expert, Dr. Anthony Fauci, said the omicron strain could be a "red flag," but more research needs to be done — and fast.
On Friday, Fauci appeared on CNN and discussed what is being done so far to better understand the new, "highly transmissible" COVID-19 strain discovered by South African scientists.
"Well certainly there is a new variant that is now in South Africa in the Gauteng Province, that has some mutations that are raising some concern, particularly with regard to possibly transmissibility increase and possibly evasion of immune response. We don’t know that for sure right now, this is really something that’s in motion and we just arranged right now, a discussion between our scientists and the South African scientists a little bit later in the morning, to really get the facts because you’re hearing a lot of things back and forth. We want to find out scientist to scientist exactly what is going on," Fauci said.
An advisory panel of the World Health Organization on Friday classified the worrying new COVID-19 variant as a highly transmissible variant of concern, naming it "omicron" under its Greek letter system.
The U.N. health agency also said early evidence on the variant, until now known by the technical term B.1.1.529, has shown an increased risk of reinfection compared to other highly transmissible variants, indicating that people who contracted COVID-19 and recovered could be more subject to catching it again with omicron. The WHO suggested that the omicron variant could pose greater risks than the delta variant, which was first detected in India and has been ravaging countries worldwide.
FILE - National Institute of Allergy and Infectious Diseases Director Anthony Fauci testifies before the Senate Health, Education, Labor, and Pensions Committee about the ongoing response to the COVID-19 pandemic. (Chip Somodevilla/Getty Images)
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The WHO announcement marks the first time in months that it has classified a COVID-19 variant as the highly-transmissible "variant of concern." The classification also applies to delta, which has become the world’s most prevalent variant. It comes amid a surge in cases of delta in Europe in particular, and at a time when many countries had eased lockdown measures and travel restrictions.
The U.S. Centers for Disease Control and Prevention confirmed that as of Nov. 26, no cases of the omicron variant have been detected in the United States.
"CDC is following the details of this new variant, first reported to the WHO by South Africa. We are grateful to the South African government and its scientists who have openly communicated with the global scientific community and continue to share information about this variant with the U.S. Department of Health and Human Services and CDC. We are working with other U.S. and global public health and industry partners to learn more about this variant, as we continue to monitor its path," a CDC statement read.
Shortly after the WHO panel made its determination, the U.S. and Canada joined the European Union and several other countries in instituting travel restrictions on visitors from southern Africa, where the variant brought on a fresh surge of infections and is thought to have originated.
The White House said the U.S. will restrict travel from South Africa and seven other countries in the region beginning Monday. It did not give immediate details except to say the restrictions will not apply to returning U.S. citizens or permanent residents, who will continue to be required to test negative before travel.
Medical experts, including the WHO, warned against any overreaction before the variant was better understood. But a jittery world feared the worst nearly two years after COVID-19 emerged and triggered a pandemic that has killed more than 5 million people around the globe.
"We must move quickly and at the earliest possible moment," British Health Secretary Sajid Javid told lawmakers.
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Omicron has now been seen in travelers to Belgium, Hong Kong and Israel as well as in southern Africa.
After news of the burgeoning omicron variant triggered travel bans around the world Friday, Moderna announced that it is testing several current booster vaccine candidates against the variant and developing a booster dose meant to target omicron specifically.
"The Moderna COVID-19 vaccine is authorized as a booster for many populations at the 50 µg dose level. The Company is working rapidly to test the ability of the current vaccine dose to neutralize the Omicron variant and data is expected in the coming weeks," Moderna wrote in its announcement.
Additionally, Moderna said it will rapidly advance an omicron-specific booster candidate (mRNA-1273.529).
"From the beginning, we have said that as we seek to defeat the pandemic, it is imperative that we are proactive as the virus evolves. The mutations in the Omicron variant are concerning and for several days, we have been moving as fast as possible to execute our strategy to address this variant," said Stéphane Bancel, chief executive officer of Moderna.
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"We have three lines of defense that we are advancing in parallel: we have already evaluated a higher dose booster of mRNA-1273 (100 µg), second, we are already studying two multi-valent booster candidates in the clinic that were designed to anticipate mutations such as those that have emerged in the Omicron variant and data is expected in the coming weeks, and third, we are rapidly advancing a Omicron-specific booster candidate (mRNA-1273.529)," Bancel said.
Pfizer, meanwhile, said if a variant ever evades the protection offered by its FDA-approved COVID-19 vaccine Comirnaty, it expects to be able to produce a "tailor-made" vaccine against that variant in approximately 100 days, pending approval from federal regulators.
"Pfizer and BioNTech are remaining vigilant, and we are constantly conducting surveillance efforts focused on monitoring for emerging variants that potentially escape protection from our vaccine. As always, we will continue to follow the science as we examine the best approaches to protecting people against COVID-19.
U.S. health officials plan to share information between scientists and health experts in South Africa to better understand if the vaccines currently available will protect the public from the new omicron variant, Fauci said.
"That’s what we’re going to be finding out because when you look at a mutation, it can give you a hint or a prediction that it might evade the immune response. What you need to do is you need to get that particular sequence of the virus, put it in a form in the lab where you can actually test the different antibodies. So you can have a prediction that it might evade or you can actually prove it," Fauci said.
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RELATED: US, Canada, EU, Japan restrict South Africa travel over Omicron variant
"Right now we’re getting the material together with our South African colleagues to get a situation where you can actually directly test it. So right now you’re talking about sort of like a ‘red flag’ that this might be an issue but we don’t know. Once you test it, you’ll know for sure whether or not it does or does not evade the antibodies that we make, for example against the virus through a vaccine or following convalescence, after you get infected when you get antibodies, do those antibodies protect you against this new virus? The answer is, we don’t know right now but we’re going to find out for sure," Fauci continued.
As people return home from their Thanksgiving travels, Fauci said the most important line of protection will continue to be getting vaccinated or getting a booster dose, despite not knowing whether or not the vaccines will adequately protect against the new strain.
"I keep saying it over and over, the next couple of months are going to be up to us. I mean, we, right now, have a tool, a very effective tool. We have too many people, 60 million people or so, who are adults who are eligible for vaccination who are not vaccinated. We’ve got to get them vaccinated, there’s no reason whatsoever not to vaccinate them. We also know that the boosters, and this is really very, very clear, the boosters increase the level of protection dramatically," Fauci stressed.
"Particularly in those individuals who have waning protection and we do know it’s a fact that after several months, people, particularly the elderly, but across the board in the age group, you have the deminution in protection over several months, which is the reason why we’re recommending that everyone 18 years or older who has received the vaccine, get the booster. You get a booster now, you can get into the winter and have a higher degree of protection. That’s the reason why we’re pushing so hard for people to ‘A,’ get vaccinated in the first place if you’re not vaccinated and ‘B,’ if you have been vaccinated and you’re six months or more following the mRNA or two months or more following the J&J, go get your booster. It really is important as we enter into this colder winter season," Fauci said.
On Nov. 19, the U.S. opened COVID-19 booster shots to all adults and took the extra step of urging people 50 and older to seek one, aiming to ward off a winter surge as coronavirus cases rise even before millions of Americans travel for the holidays.
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Under the new rules, anyone 18 or older can choose either a Pfizer or Moderna booster six months after their last dose. For anyone who got the single-dose Johnson & Johnson vaccine, the wait already was just two months. And people can mix-and-match boosters from any company.
The Associated Press and Stephanie Weaver contributed to this report.