On Tuesday, two weeks following his last public appearance in late June, Fauci appeared on MSNBC and joined a White House press briefing by video conference to caution regarding the spread of the BA.5 variant, a subvariant of the Omicron strain.
He called on Americans to get vaccine booster shots and announced that health officials are now "recommending" people return to wearing masks in indoor group settings.
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Fauci, 81, had been lying low for several weeks after a prolonged bout with COVID last month, yet seems to have completely recovered.
He first tested positive for the virus on June 14 and initially appeared to recover after taking the antiviral pill Paxlovid.
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Then on June 28, while speaking remotely at the Foreign Policy Global Health Forum, he revealed that his symptoms had returned. It marked his last public appearance until this week.
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The CDC has cautioned that Paxlovid may be associated with "rebound" cases of COVID, in which symptoms return after an initial negative test, yet states that rebound cases are generally mild.
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In his public appearances on Tuesday, Fauci urged Americans to get a second booster shot to combat the spread of the BA.5 variant, an Omicron subvariant that seems to resist immunity from prior infections.
"Well, it's something we absolutely need to take seriously. It has a transmission advantage over the prior variants that were dominant," he announced on MSNBC.
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Fauci continued that it "has a transmission advantage which is one of the reasons why we're seeing throughout several regions of the country, including, in particular, the New York area, you're starting to see cases go up."
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He stated vaccines and boosters were the key weapons in fighting increasing infections and downplayed the notion that new restrictions or mandates would be imposed on Americans if cases soar once again.
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"We're not talking mandating anything, but we're saying recommending people when in indoor congregate settings to wear a mask," he stated.
"Those are simple, doable things that can help prevent us from having even more of a problem than we're having right now."
Fauci further joined a White House briefing alerting Americans to take precautions in indoor settings and prepare for the surging BA.5 variant – even if they have already recovered from a recent case of COVID.
"Immunity wanes, so it is critical to stay up to date with COVID 19 vaccines as primary vaccines and as boosters were appropriate," he stated on a White House call with reporters Tuesday.