President Donald Trump tested positive for the coronavirus days before he shared the debate stage with then-Democratic presidential nominee Joe Biden in September 2020, a according to his former chief of staff and two others familiar with the former president’s test.

Trump’s positive test for the virus was on Sept. 26, 2020, according to an account by former White House chief of staff Mark Meadows in a new book obtained by The Guardian. The Meadows account was confirmed Wednesday by two people who requested anonymity to discuss their knowledge of the former president’s health.

The timing means Trump would have had reason to believe he may have been infected with coronavirus three days before the Sept. 29 presidential debate and six days before he was hospitalized for COVID-19 at Walter Reed National Medical Center.

The White House did not reveal the positive test publicly or to debate organizers at the time, Meadows wrote in his book, which is due to be published in coming days, that Trump received a negative result from a different test shortly after his positive one. It is unclear if Trump provided a separate sample for another test on Sept. 26 that yielded a negative result, or if the sample from his positive test was simply retested through other means.

In a statement Wednesday morning, Trump denied Meadows’s account of events.

“The story of me having COVID prior to, or during, the first debate is Fake News,” Trump said. “In fact, a test revealed that I did not have COVID prior to the debate.”

Although both Trump and Meadows have a track record as unreliable narrators who do not always convey the truth, the two other officials familiar with the episode said Meadow’s account was accurate.

The revelation provides new evidence of Trump’s often reckless and cavalier approach to his own health and the health of those around him as he struggled through a chaotic response to the pandemic. In addition to potentially endangering Biden, his chief political rival, he also may have put moderator Chris Wallace and dozens of staff at risk during the 90-minute debate. The president also risked transmitting virus to others during as series of other close interactions he had during the time between the Sept. 26 test and his Oct. 2 hospitalization.

At least six of Trump’s aides who had close interactions with him starting on or after Sept. 26 later tested positive for COVID, including former first lady Melania Trump, senior adviser Hope Hicks, policy advisor Stephen Miller and press secretary Kayleigh McEnany, according to a Washington Post tally.

Trump on Wednesday was furious that Meadows revealed the anecdote in his forthcoming book and that it was published via the liberal-leaning Guardian website, according to a person familiar with the former president’s reaction, who requested anonymity to reveal a private conversation.

Meadows through an emissary has offered to put out a statement “clarifying things,” but that offer was rejected, the person said.

A spokesman for Meadows did not respond to a request for comment.

Biden was asked about the reports Wednesday after he delivered a speech on the nation’s clogged supply chains. “I don’t think about the former president,” Biden said.

During the White House briefing Wednesday, Anthony Fauci, a top infectious-diseases expert under both presidents, said he did not know about Trump’s test. “I certainly was not aware of his test positivity or negativity,” Fauci said.

“I’m not going to specifically talk about who put who at risk,” Fauci added. “If you test positive you should be prudent and self-quarantine yourself.”

According to The Guardian account of his book, Meadows writes that “nothing was going to stop [Trump] from going out there” at the first presidential debate in Cleveland. The debate rules required candidates to have tested negative for the virus 72 hours ahead of the start time; it is not clear when the negative test was administered.

In addition to attending the debate, Trump participated in a number of other events after his positive diagnosis – including a campaign rally in Pennsylvania, an indoor news conference at the White House and a close-quarters exchange with reporters aboard Air Force One – potentially putting dozens of other people at risk.

“Hours after he received the call from Meadows informing him of a positive test, Trump came to the back of AF1 without a mask and talked with reporters for about 10 minutes,” New York Times White House reporter Michael Shear wrote in a tweet Wednesday morning. “I was wearing a mask, but still got COVID, testing positive several days later.”

Meadows writes that Trump acted as though he had “full permission to press on as if nothing had happened” upon receiving the negative test after his initial positive test Sept. 26. But Meadows writes that he “instructed everyone in his immediate circle to treat him as if he was positive,” according to the excerpts.

“I didn’t want to take any unnecessary risks, but I also didn’t want to alarm the public if there was nothing to worry about – which according to the new, much more accurate test, there was not,” Meadows writes, according to the newspaper.

It was not until 1 a.m. on Oct. 2 that Trump revealed that he and his wife had tested positive for the virus. Trump was taken to Walter Reed National Military Medical Center for treatment later that day. By that point, a host of White House officials had also tested positive for the coronavirus.