"That's a very good question, an important question and we did struggle with that, but we wanted to see if we could buy time temporarily," Fauci announced. "So I do hope that this gets sorted out and lifted before it has any significant impact."
Fauci was prodded by a journalist from Ethiopia regarding why President Joe Biden's travel ban - which blocks entry for most non-citizens from eight African nations - includes some places where no cases of the Omicron variant had been found.
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The countries included South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique, and Malawi, with South Africa accounting for the majority of the cases.
In the meantime, the U.S. reported its first case of the COVID-19 Omicron variant in California earlier Wednesday - with Fauci reading a remark about it at the top of his appearance.
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Biden's top medical specialist then fielded questions from reporters for roughly 20 minutes.
Fauci was asked if the narrowed testing window for travelers coming into the U.S. - with tests expected to be required now within 24 hours before an individual's flight - should apply to everyone.
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"The answer is yes," Fauci stated.
He was then asked by Fox News' Peter Doocy how that would apply to migrants coming over the U.S.-Mexico border.
"That's a different issue," Fauci demurred.
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He continued, "We still have Title 42 with regard to protection at the border, so there are protections at the border."
Title 42 has enabled the U.S. to dismiss migrants throughout the coronavirus pandemic, citing a public health risk.
"There is testing at the border under certain circumstances as you know," Fauci further offered.
Throughout the briefing, Fauci - who worked under former President Donald Trump as well - was asked regarding the revelation in Mark Meadows' forthcoming book that Trump had got the positive result in one COVID test three days before participating in the presidential debate.
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Three days after that, he declared he had COVID.
"Well, I certainly was not aware of his test positivity or negativity," Fauci announced.
Meadows wrote that White House physician Sean Conley was aware of the test and tried to prevent Trump from going to a Pennsylvania rally after he tested positive.
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When a second test came back negative, Trump proceeded as planned.
"If you test positive you should be quarantined," Fauci announced would have been his medical advice.
"I would recommend to anyone, whether it's the president or any of my patients, or any of the people I deal with, that if you test positive you should be prudent and quarantine yourself," Fauci said.