Jimmy Fallon is recovering after contracting COVID-19.

On Monday, the host of “The Tonight Show” shared in an Instagram post that he tested positive for COVID-19 during the show’s break over the Christmas holidays.

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“Hey guys, on the first day of our holiday break I tested positive for COVID,” Fallon wrote. “I was vaccinated and boostered which made me lucky enough to only have mild symptoms.”

The late-night host continued, “Thank you to the doctors and nurses who work so hard around the clock to get everyone vaxxed. Thank you to NBC for taking the testing protocols so seriously and doing a great job – and also thanks for putting me in the ‘What ‘chu talkin’ about Willis?’ isolation room when they told me the news.”

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In the comments, Reese Witherspoon wrote, “Hope you had a speedy recovery!”

Fallon has evidently recovered well, as he hosted “The Tonight Show” Monday, with guests Anthony Anderson, Adam Devine and Carly Pearce.

He explained on the show how his wife Nancy and daughters Frances, 7, and Winnie, 8, had driven upstate while he quarantined in New York City.

However, his girls ended up testing positive as well, which meant they could be together for the holidays in the end.

“They’re fine,” Fallon assured the audience. “Everyone is fine, they had the sniffles. Frannie had sniffles for, like, two days. Winnie had no symptoms at all.

“But that meant I could go home and spend the holidays with the kids, so I did. It was a Christmas miracle.”