“Did Trump try infecting Biden with COVID at debate?”

The former president, Trump, first received a positive coronavirus test days ahead of his first debate with Biden.

President Donald J. Trump tested positive for coronavirus three days before his first debate with Joseph R. Biden Jr. in 2020, two former administration officials said Wednesday.

The White House did not announce the positive test at the time, and the president received a negative result shortly afterward and carried on with a campaign rally and the debate, the officials said. The account was first reported by The Guardian, which cited a forthcoming book by Mr. Trump’s chief of staff, Mark Meadows.

The two former officials, who spoke on condition of anonymity because they were not authorized to discuss the matter publicly, confirmed the timeline on Mr. Trump’s test results contained in “The Chief’s Chief,” by Mr. Meadows, Mr. Trump’s fourth and final White House chief of staff.

Mr. Trump’s positive result was revealed only after a top adviser, Hope Hicks, was reported to be sick with Covid-19. At the time, Mr. Trump intimated in an interview with Fox News that Ms. Hicks might have given him the virus.

But Mr. Meadows wrote in his book that three days earlier, on Sept. 26, Mr. Trump received a positive test shortly before departing the White House for Air Force One to travel to Pennsylvania for a rally.

According to The Guardian, Mr. Meadows wrote that the positive test was taken with an older testing kit, and that the new one was the “Binax system, and that we were hoping the first test was a false positive.” Mr. Trump took the second result as “full permission to press on as if nothing had happened,” Mr. Meadows wrote, according to The Guardian. Mr. Meadows asserted in the book that he “instructed everyone in his immediate circle to treat him as if he was positive” during that trip.

The two former officials who confirmed the positive test did not recall Mr. Meadows giving such a directive. And a few hours after the positive test was received, Mr. Trump walked to the back of Air Force One and chatted with reporters, not wearing a mask. One of the reporters, who works for The New York Times, later tested positive for the virus.

The day after the positive result, Mr. Trump attended an event for military families.

Mr. Meadows wrote in his book that Mr. Trump appeared physically off around the time of that test, although by the time of the first debate against Mr. Biden, he seemed a little better.

“His face, for the most part at least, had regained its usual light bronze hue, and the gravel in his voice was gone,” Mr. Meadows wrote, according to The Guardian. “But the dark circles under his eyes had deepened. As we walked into the venue around five o’clock in the evening, I could tell that he was moving more slowly than usual. He walked like he was carrying a little extra weight on his back.”

In a statement released by his office, Mr. Trump replied, “The story of me having Covid prior to, or during, the first debate is Fake News. In fact, a test revealed that I did not have Covid prior to the debate.”

On Twitter, CNN correspondent John Harwood said, “does anyone that Trump, suspecting he had covid, would have WANTED to infect Biden?”