Dr. Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, told viewers on Weekend TODAY Saturday not to let their guard down as the omicron variant, a new strain of COVID-19 spreads internationally.
He also told co-anchors Kristen Welker and Peter Alexander that it was possible the omicron variant is already in the United States.
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"I would not be surprised if it is. We have not detected it yet, but when you have a virus that is showing this degree of transmissibility and you're already having travel-related cases that they've noted in Israel and Belgium and other places, when you have a virus like this, it almost invariably is ultimately going to go essentially all over," Fauci said.
The White House has since announced restrictions for travelers from eight African countries that are scheduled to begin Monday.
Experts are concerned the omicron variant might be more transmissible or may lead to more severe illness, and its high number of mutations have some concerned it could evade vaccines, but Fauci emphasized that more information is necessary.
So far, omicron has been found in multiple countries, including Israel and Belgium, after it was initially discovered in South Africa. Fauci said that because the variant is so transmissible, the travel restrictions on African nations are a way of buying time.
"The issue of blocking travel from a given country is to just give us time to assess it better," Fauci said. "That's the reason for doing that, not any reason to panic, but we want to give us some time to really fill in the blanks of what we don't know right now," the chief medical advisor to President Biden said.
Fauci added that public health experts are trying to find answers to questions such as whether the omicron variant causes more severe illness and whether it can evade protection from vaccines or treatments.
"It also has a bunch of mutations that would suggest it could evade the protection, for example, of monoclonal antibodies and perhaps even convalescent plasma for people who have been infected and recovered, and possibly vaccine. These are all maybes, but the suggestion is enough," Fauci said.
The quick spread of the variant is also concerning, Fauci said.
"It seems to have really spread rather rapidly in South Africa, even though the numbers are relatively small, its ability to infect people who have recovered from infection and even people who have been vaccinated make us say, 'This is something you've got to pay really close attention to, and be prepared for something that's serious,'" Fauci explained. "It may not turn out that way, but you really want to be ahead of it, and that's the reason why we're doing what we're doing."
Fauci emphasized that people shouldn't panic about the new COVID-19 variant, but should continue to take precautions like wearing masks, social distance and avoid large, indoor gatherings. He said that the threat of this variant, or any other variant, should also encourage people to get vaccinated.
"It is absolutely essential that unvaccinated people get vaccinated and that vaccinated people get boosters," Fauci said. "We know now clearly that when you get a booster shot ... you dramatically increase that level of protection."
Fauci added, "The vaccines that we use may very well be able to contain this, and then (omicron) won't be as serious as some people are surmising it might be. A lot of unknowns, which is the reason why we're all over this. And as they say, you assume something that might be worse than it is, but better that than underestimating. You don't want people to panic, but you want to know that we're doing everything we can to stay ahead of this."
This story first appeared on TODAY.com. More from TODAY: