The Omicron COVID-19 variant could already be in the United States, according to Dr. Anthony Fauci.
"I would not be surprised if it is," Fauci, 80, told Peter Alexander and Kristen Welker Saturday on Weekend Today.
Fauci said the strain — currently known as B.1.1.529 — "has a large number of mutations" particularly affecting the virus' ability to bind to cells in the nose and lung.
"We have not detected it yet [in the U.S.]," he added, "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 in other places — when you have a virus like this, it almost invariably is ultimately going to go essentially all over."
Based on mutations identified by researchers, Fauci said the strain "likely will be more transmissible" than others, including the highly transmissible Delta variant. "We don't know that yet," he noted in the interview, "but you have to assume that would be the case."
Fauci also raised concern over whether the new variant "could evade the protection" of key treatments such as monoclonal antibodies and convalescent plasma for those who have contracted and recovered from COVID-19 — "and possibly vaccine(s)."
"These are all maybes, but the suggestion is enough," Fauci shared.
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The Omicron variant has spread rapidly through South Africa after it was first discovered in Botswana. The strain, which has now made its way to Europe, prompted a World Health Organization panel meeting on Friday, where the variant received its name and was classified as a highly transmissible "variant of concern."
On Weekend Today, Fauci emphasized the importance of getting ahead of the virus while possible, which he said is why the country is already taking precautions.
"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,'" the nation's leading infectious disease expert explained.
Blocking travel from countries with reported cases, Fauci added, allows experts more time to assess the situation. "The issue of blocking travel from a given country is to just give us time to assess it better," he noted.
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In the meantime, the chief medical advisor to President Biden urged Americans to get vaccinated against the deadly virus and not let their guard down in "congregate settings" where the virus can be increasingly transmissible.
According to Weekend Today, cases of COVID-19 are up at least 10% over the last two weeks in at least 15 states, largely in the Eastern portion of the country. More than 100,000 cases are being reported each day.
Fauci also said the country's fate "is in our own hands," adding that the Omicron variant "is yet again another reason" for Americans to protect themselves against COVID-19.
"It is absolutely essential that unvaccinated people get vaccinated and the vaccinated people get boosters," urged Fauci. "We know now clearly that when you get a booster shot ... you dramatically increase the level of protection [you have]."
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