(NEW YORK) — 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.

Here is how the news developed on Sunday. All times Eastern:

Oct 04, 11:23 pm
President wants to leave hospital as soon as possible

Sources tell ABC News that President Trump was in good spirits Sunday, and was insisting that he wants to leave Walter Reed Medical Center as soon as possible.

Aides are pushing Trump to relax, sources say.

A timetable on Trump’s release was still not finalized as of Sunday night, sources said. Doctors said earlier Sunday that Trump could leave the hospital as early as Monday.

Oct 04, 9:08 pm
White House says ‘appropriate precautions’ taken for Trump’s ride

The White House says President Trump’s drive-by outside Walter Reed hospital Sunday evening was “safe to do,” even as he fights the coronavirus.

Trump spokesman Judd Deere said “appropriate precautions” were taken for the short ride, giving little details other than PPE was used.

“The movement was cleared by the medical team as safe to do,” Deere said in a statement.

However, infectious disease experts tell ABC News that the president is likely still infectious.

Dr. William Schaffner,  a professor of preventive medicine at Vanderbilt University, said, “You have to have been a certain number of days symptom-free, and 10 days from the onset of your illness — or the date of positivity of your test.”

“He’s done something that no one would recommend,” he told ABC News, saying that he may have put the Secret Service members who rode with him at risk.

“This did not appear to be an essential trip,” Schaffner said.

Oct 04, 8:04 pm
Biden tests negative

Vice President Joe Biden’s campaign said he underwent PCR testing today and the results came back negative.

The campaign wouldn’t provide more details about the test.

Oct 04, 7:59 pm
Barr is in self-quarantine, gets third negative test result

Department of Justice spokeswoman Kerri Kupec told reporters that Attorney General Bill Barr is self-quarantining at home, but has so far tested negative for the virus.

The spokeswoman would not provide more details about Barr’s self-quarantine.

This is the third time he has tested negative for COVID-19 since last Tuesday’s debate. 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 while not wearing a mask during the event.

Oct 04, 6:23 pm
Trump did not disclose first positive test

Before making an appearance on Sean Hannity’s show on Fox News Thursday evening, President Trump had already tested positive that evening for COVID-19 from a rapid test, multiple sources familiar with the matter told ABC News.

The president did not reveal the results of his first positive test as he awaited results from the more accurate PCR test. However he confirmed to Hannity that top aide Hope Hicks had tested positive.

“She did test positive. I just heard about this. She tested positive,” Trump said.

“And I just went out with a test, I’ll see — you know, ‘cause we spend a lot of time — and the first lady just went out with a test also,” he said.

Oct 04, 5:43 pm
Trump leaves Walter Reed briefly for drive-by appearance

With little warning, President Donald Trump left Walter Reed Hospital for a few minutes in his motorcade Sunday evening to greet supporters who were outside.

Trump, appearing with a mask from the window of his vehicle, was seen waving to a crowd.

The president tweeted a video before the drive-by appearance thanking his supporters and saying he was going to “make a little surprise visit.”

— Donald J. Trump (@realDonaldTrump) October 4, 2020

Trump also said in the video that he visited soldiers and first responders at the hospital.

It was not immediately known if there was anyone else in the car aside from the driver. A Secret Service spokesperson declined to comment on the impact of Trump’s trip on the health and safety of their agents, saying they “do not comment on presidential protection.”

A senior administration official told ABC News afterward that Trump had returned to the hospital and that he had not been discharged.

Administration member Judd Deere subsequently put out a statement saying that, “President Trump took a short, last-minute motorcade ride to wave to his supporters outside and has now returned to the Presidential Suite inside Walter Reed.”

There have been no updates on Trump’s condition from his physicians since earlier in the day, when they told reporters he could be released as early as Monday.

Oct 04, 4:16 pm
Trump tweets appreciation for supporters outside hospital

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.

I really appreciate all of the fans and supporters outside of the hospital. The fact is, they really love our Country and are seeing how we are MAKING IT GREATER THAN EVER BEFORE!

— Donald J. Trump (@realDonaldTrump) October 4, 2020

Oct 04, 4:09 pm
White House identifies over 200 Bedminster guests to health officials

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.

Oct 04, 3:46 pm
AG Bill Barr tests negative, cancels some in person events

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.

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.

Oct 04, 2:44 pm

Independent voter reacts to Trump diagnosis, activities

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 Dwye

Oct 04, 2:27 pm

More on steroid treatment given to Trump

Doctors treating President Trump announced that he has been given the steroid Dexamethasone to combat symptoms of the coronavirus.

Dexamethasone, a steroid treatment, is seeing positive results in some patients.

A study in the United kingdom in June found that dexamethasone increased survival in severely ill COVID-19 patients who needed help breathing.

Trump’s condition is improving, doctors say, but he did have two episodes where his oxygen levels dropped.

Prescribing dexamethasone for President Trump may be appropriate considering he received oxygen at some point during his illness.

“It’s a borderline indication within the physicians prerogative,” said Dr. William Schaffner, professor of preventative medicine in the Department of Health Policy as well as professor of medicine in the Division of Infectious Diseases at Vanderbilt University School of Medicine in Nashville, Tennessee.

Although the U.K. study appeared promising, dexamethasone only was demonstrated to help patients who have severe COVID-19 and need help breathing, through ventilation or oxygen assistance. The steroid treatment has not been proven to help people with a more mild COVID-19 illness, which accounts for most cases.

In fact, it may not be safe to use in patients with mild illness. In the U.K. study, dexamethasone “non-significantly increases death if used in milder patients with COVID-19,” said Dr. Todd Ellerin, director of Infectious Diseases at South Shore Health. He warned that for patients with milder COVID-19 illness “the risks of the medication likely outweigh the benefits.”

– ABC News’ Sony Salzman contributed to this report

Oct 04, 1:50 pm

Masks mandatory at White House for NSC staff

White House national security adviser Robert O’Brien while speaking to reporters at the White House on Sunday announced that mask wearing is now mandatory for National Security Council staff.

“We made mask wearing mandatory for National Security Council staff,” O’Brien said.

Mask wearing was previously voluntary.

– ABC News’ Elizabeth K. Thomas

Oct 04, 1:40 pm

Pence, wife negative for COVID-19

Vice President Mike Pence and second lady Karen Pence again have been tested Sunday for the coronavirus and received negative test results, a White House official told ABC News.

This is the third day since President Donald Trump’s coronavirus diagnosis that they have received a negative test result.

– ABC News’ Elizabeth K. Thomas

Oct 04, 1:33 pm

Pelosi has not been updated on Trump’s condition

House Speaker Nancy Pelosi, D-Calif., in an appearance on CBS’s “Face the Nation” on Sunday, said she still hasn’t heard from the president’s team regarding his condition or any continuity of government matters.

“We’re getting our information the way everyone else is: in the media. But in terms of the succession, that’s an ongoing process. Sadly, at this time, it comes to the forefront,” she said.

Amid calls to improve the testing system available to lawmakers and Capitol Hill denizens after this week, Pelosi said she has confidence in the recommendations of the Office of the Attending Physician of Congress — noting that the sheer number of people working on the Hill (approximately 20,000 employees of all kinds) would pose a challenge for testing.

“There could be some sampling. Let’s depend on science on how deal with it,” she said.

– ABC News’ Benjamin Siegel

Oct 04, 12:23 pm

Trump was given supplemental oxygen, doctors confirmed

The medical team refused on Saturday to confirm that President Trump was given supplemental oxygen as part of his treatment for the coronavirus, but on Sunday Dr. Sean Conley said the president had been in fact given supplemental oxygen at least once.

Sources close to Trump told ABC News the president was having trouble breathing and received supplemental oxygen on Friday at the White House after his oxygen levels dropped. This in part prompted the president to be transferred to Walter Reed Hospital late Friday afternoon.

When asked why that information was not disclosed until Sunday, Conley said he was “trying to reflect the — the upbeat attitude that the team, the president, that this course of illness has had.”

“I didn’t want to give any information that might steer the course of illness in another direction. And in doing so, you know, it came off that we were trying to hide something which wasn’t necessarily true.”

Conley was asked if Trump had been given a second round of supplmental oxygen on Saturday and he said he’d “have to check with the nursing staff” but if additional oxygen was administered, it would have been “very, very limited.”

Oct 04, 12:13 pm

Doctors asked about Trump not wearing a mask in videos

Dr. Sean Conley and the medical team were asked about videos that showed President Trump not wearing a mask while updating the public on his current condition.

Conley told reporters on Sunday that the president “wears a mask anytime he’s around us” and that all hospital officials are wearing their N95 masks and full personal protective equipment.

Oct 04, 12:05 pm

Doctors hope to discharge Trump as early as Monday

Dr. Garibaldi, part of the medical team treating President Trump, said if the president continues to look and feel as well as he does Sunday, the hope is he can be discharged as early as Monday to return to the White House where he can continue his treatment.

Oct 04, 12:05 pm

Trump has had no fever since Friday morning

Trump’s medical team said the president has remained without a fever since Friday morning and his vital signs are stable. He is not complaining of any shortness of breath or other significant respiratory symptoms.

Trump is walking around the White House medical unit at Walter Reed without any limitation or disability.

Doctors continue to monitor cardiac, liver and kidney function, which continue to show normal findings.

Oct 04, 11:53 am

Trump’s oxygen levels have dropped twice since onset of symptoms

Dr. Conley said over the course of exhibiting coronavirus symptoms, President Trump has experienced two episodes of “transient drops” in his oxygen saturation.

The medical team decided to administer the steroid dexamethasone based on the timeline from the initial diagnosis and concerns over “possible rapid progression of the illness.”

“Thursday night into Friday morning when I left the bedside the president was doing well, with only mild symptoms and his oxygen was in the high 90s,” Conley said. “Late Friday morning, when I returned to the bedside, the president had a high fever and his oxygen saturation was transiently dipping below 94%. Given these two developments, I was concerned for possible rapid progression of the illness.”

Oct 04, 11:47 am

Trump continues to improve, doctors say

President Trump’s condition has continued to improve, physician to the president Dr. Sean Conley told reporters on Sunday. He has not had a fever since Friday morning and is not complaining of shortness of breath.

Oct 04, 8:06 am

Rudy Giuliani says Trump ‘felt pretty bad the first day’

Rudy Giuliani said on Fox News on Sunday morning that he held about a 35 to 40 minute phone conversation with Trump on Saturday where they went over his health and the campaign.

“I had to kind of get him off the phone so he went back and rested,” Guiliani said in the interview.

Giuliani says the president told him that he “felt pretty bad the first day”, but, as of 3 p.m. on Saturday that he “felt perfectly fine”, had no fever and was a little tired.

Giuliani also commented on his own personal health and said he got tested two days ago and will be tested again “probably tomorrow.”

Giuliani said he tested negative and currently has no symptoms of COVID-19.

ABC News’ Ahmad Hemingway contributed to this report.

Oct 04, 4:43 am

Bodyman for Trump tests positive

Nick Luna, the current director of Oval Office Operations and bodyman to President Trump has tested positive for the coronavirus, sources familiar with the matter confirmed to ABC News tonight.

Luna travels with the president pretty much wherever he goes and sources with direct knowledge tell ABC News that Luna was with Trump on most of his travels this week, including most recently a trip with the president and Hope Hicks, who later tested positive for COVID, on Wednesday. He did not travel to Trump’s fundraiser in Bedminster, New Jersey, on Thursday.

Luna’s positive test could have other implications: He is married to another White House aide who happens to be an assistant to Jared Kushner, the president’s senior advisor and son-in-law.

ABC News’ John Santucci contributed to this report.

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