WASHINGTON  — President Joe Biden received a negative coronavirus test result on Wednesday, days after he was exposed to a staffer who later test positive for the virus.

Biden met with “mid-level staffers” Friday and received positive results on Monday. While on Air Force One, the senior aide was able to spend about thirty minutes next to the president as he traveled from South Carolina and Philadelphia. White House press secretary Jen Psaki said on Monday.

Psaki stated that the person was vaccinated, boosted and had previously tested negative for Covid before travel on Air Force One. He did not feel any symptoms until Sunday.

Sources tell NBC that Biden was hiding behind a mask throughout his interaction with the staff member who tested positive.

President is fully vaccinated.

Biden’s tests come at a time when the Omicron variant sweeps America, and becomes the dominant strain for U.S. Covid-19 patients.

Last week, Dr. Anthony Fauci, Biden’s top medical advisor, urged people to get vaccines and booster shots to fight off the new variant.

It is the most transmittable virus in Covid we have dealt with. It is expected to quickly take over here. “That’s the one thing that we know,” Fauci said to a virtual audience of U.S. Chamber of Commerce Foundation members.

Mike Calia of CNBC contributed from New York to this report.

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