The president had already tested positive Thursday when he appeared on Fox News.
President Donald Trump's condition is continuing to improve as he fights a coronavirus infection, doctors say, and he may be able to leave Walter Reed Medical Center as early as Monday -- even as details emerge that the president allegedly initially tested positive for COVID-19 earlier than he acknowledged.
Doctors also reported that Trump, over the course of exhibiting coronavirus symptoms, had earlier experienced two episodes of "transient drops" in his oxygen saturation.
Yet the president was feeling well enough Sunday evening to briefly leave Walter Reed for a surprise drive-by, waving to supporters outside the hospital.
Meanwhile, numerous questions remain about how many people at the highest levels of government had been exposed to the virus after a week of events involving the president where social distancing and mask-wearing were lax in the White House and elsewhere.
President Donald Trump posted on Twitter Sunday afternoon that he appreciates "all of the fans and supporters outside of the hospital."
The medical team treating the president is hopeful that he will be discharged from Walter Reed Medical Center on Monday.
The New Jersey Health Department tweeted out an update Sunday about the people who attended an event with President Trump at the Trump National Golf Course in Bedminster, New Jersey, last week, shortly before the president and other administration officials tested positive for COVID-19.
It was initially reported that about 100 guests attended the event, but the list the White House sent to the Health Department included the names of 206 people who attended events with those later determined to be infected with the coronavirus.
"DOH has reached out to these individuals to make them aware of possible exposure and recommend that they self-monitor for symptoms and quarantine if they were in close contact with the President and his staff," the health department tweeted.
Health officials are currently interviewing the club’s staff members, all of whom live in Somerset County, and providing health recommendations. The Health Department has begun contract tracing for those guests, and urging any concerned members to quarantine for 14 days.
"Attendees that are seeking a test should consider waiting at least 5-7 days from the event. While the risk is low, a negative test earlier than that time cannot definitively rule out that COVID-19 will not develop," the agency tweeted.
A spokeswoman for the Department of Justice told reporters on Sunday that Attorney General Bill Barr took "two rapid tests and one pcr test since Friday morning." All of the tests came back negative, according to DOJ spokeswoman Kerri Kupec.
"Out of an abundance of caution, he went to the department for only one meeting on Friday, stayed home this weekend other than getting tested, and will stay home tomorrow," she said.
A DOJ official also told ABC News that Barr is postponing a planned trip to St. Louis this week, which was supposed to be a part of the department’s “Operation Legend” initiative.
Barr attended the Sept. 26 event at the White House where President Trump announced Judge Amy Coney Barrett as his Supreme Court Justice nominee.
Several Trump administration officials who contracted the virus last week, including Kellyanne Conway and former Gov. Chris Christie, attended the event and were not wearing masks during the outdoor ceremony.
Barr was photographed talking with Conway and not wearing a mask during the event.
-ABC News' Alexander Mallin
ABC News spoke to one registered independent about his reaction to Trump testing positive and his activities leading up to the positive test result.
Rob Gorski, a former EMT and single father of three sons with autism in Akron, Ohio, said he was "very angry" that Trump "so willingly put so many people in harms way after knowing he'd been directly exposed to COVID-19."
"Trump and the others in the White House may do just fine, and I hope they do recover because no one deserves to die like that. But what about everyone else who they infected? They may not recover and they may have been doing everything right. They don't deserve that," he said.
ABC News Live Prime spoke with Gorski and three other families of special needs kids about how they are surviving the pandemic and back-to-school season.
-ABC News' Devin Dwyer
