That backdrop has raised the stakes for a vice presidential debate that in most election years would be considered a forgettable political event. The meeting was historic because Ms. Harris is the first Black woman and person of Indian descent to be a major party's vice presidential nominee.

Although two more debates between Mr. Trump and Mr. Biden are scheduled, it remains unclear if they will take place. The president said Tuesday he wants to participate in a second debate against Mr. Biden scheduled for Oct. 15, which would be two weeks after the president first tested positive.

Ahead of a debate in which the vice president was set to step into the spotlight, Mr. Trump continued to dominate headlines, releasing a video on Twitter in which said, "This was a blessing from God that I caught it." He also left the White House residence, where he was isolating, to hold a meeting in the Oval Office.

The Centers for Disease Control and Prevention's guidelines say people who have contracted the virus can stop isolating after 10 days have passed since the onset of symptoms, as long as they haven't had a fever in 24 hours and their other symptoms are improving.

Mr. Biden told reporters Tuesday he was looking forward to debating the president, but he said the debate should not take place if Mr. Trump still has Covid-19. "I just hope all the protocols are followed," he said.

Write to Tarini Parti at Tarini.Parti@wsj.com and Andrew Restuccia at Andrew.Restuccia@wsj.com

(END) Dow Jones Newswires

10-07-20 2338ET