Dr. Anthony Fauci said fully vaccinated people may “want to consider” wearing masks indoors to help protect against the Delta coronavirus variant.

Dr. Fauci, President Joe Biden’s chief medical advisor, told CNBC on Wednesday that “if you want to go the extra mile of safety even though you’re vaccinated when you’re indoors, particularly in crowded places, you might want to consider wearing a mask.”

Fauci explained that wearing a mask indoors was “suggested” when a virus was spreading fast in a community. 

“This virus is clearly different than the viruses and the variants that we’ve had experience with before. It has an extraordinary capability of transmitting from person to person,” Fauci said.

The Centers for Disease for Disease Control and Prevention (CDC) recommends that fully-vaccinated people don’t need to wear masks, except in certain situations, for example during flights.

More than 161 million Americans are fully-vaccinated, or 48% of the population, according to the Centers for Disease for Disease Control and Prevention.

Some states have already urged fully-vaccinated citizens to put their masks back on.

The Los Angeles County Department of Public Health said June 28 that it “strongly recommends everyone, regardless of vaccination status, wear masks indoors in public places as a precautionary measure,” citing the more-infectious Delta variant.

Clark County, Nevada, home to Las Vegas, re-introduced mask mandates indoors for all workers on Wednesday.

Despite his views on masks, Fauci said that “the easiest and best and most effective way that we can prevent the emergence of a new variant and crush the already existing Delta variant is to get everyone vaccinated.”

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