The president, who has been staying on the island with his family this Thanksgiving weekend, was seen inside Murray's Toggery Shop with his mask encompassing his neck and not covering his mouth. A large "Face Covering Required" sign could be seen on the front door of the shop.
The island re-established its indoor mask mandates earlier this month at a town conference on November 18. They decided to return to indoor masking because scientists discovered a predominance of the virus in island sewage.
Nantucket has a relatively low number of cases and one of the highest vaccination rates in the nation, though the sewage showing a prevalence of the virus instantly provoked the return of indoor mask mandates for at least two weeks.
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Biden, who is vaccinated, has repeatedly told Americans to wear masks indoors.
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The president spent much of his Saturday shopping in Nantucket, joined by his son Hunter and three of his grandchildren, including Hunter's infant son Beau, named for the president's late eldest son.
President Biden and one of his granddaughters, Finnegan, were later greeted by Father John Murray for mass at St. Mary Our Lady of the Isle Catholic Church.
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The White House announced that Biden has been "fully briefed" on Omicron as concerns grow over the new super mutant variant - and the president's top health specialist, Dr. Anthony Fauci, announced he "wouldn't be surprised" if the strain was already in the U.S.
The Dutch health ministry announced Saturday that no less than 61 new cases of Covid entered the Netherlands from South Africa, leading Dr. Anthony Fauci to sound the alarm regarding the dangers Omicron poses to Covid-weary US residents.
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When asked if he believes Omicron is already in the U.S. while on the Today Show Saturday morning, Fauci said: "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...it almost invariably is ultimately going to go all over."
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"You have to be careful and assume that that's the case," he continued, remarking that Omicron could possibly "evade" vaccinations.
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He further showed concerns regarding "transmissibility" as Biden says U.S. citizens and green card holders from other regions of Africa will still be permitted to travel to the U.S.
Meanwhile, Israel on Saturday announced it would ban the entry of all foreigners into the nation and reintroduce counter-terrorism phone-tracking technology in order to contain the spread of a new and possibly more contagious coronavirus variant first detected in South Africa.
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