President Donald Trump surprised supporters who gathered outside the Walter Reed hospital on Sunday by passing by and greeting them in an unannounced move. The President wore a mask as he waved from the back seat of a black SUV, while supporters chanted: "USA! USA!"

It was the President's first appearance in public since he was evacuated to the hospital on Friday. Earlier on the day, he had said: "It's a very interesting journey. I learned a lot about COVID," according to Reuters. However, he was criticized for the impromptu ride-by.

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Democratic presidential challenger Joe Biden tested negative again for the disease that has killed more than 200,000 Americans, his campaign said on Sunday. The former vice president, who shared a debate stage with Trump last Tuesday, previously tested negative in two tests on Friday, the day Trump disclosed his coronavirus infection.

President Donald Trump
The White House released photos of President Donald Trump working from Walter Reed Military Medical Center in Maryland, where is receiving treatment for Covid-19, on Oct. 3, 2020. Official WH Photos by Joyce Boghosian

Doctors said the president was improving, although they were monitoring the condition of his lungs after he received supplemental oxygen. They said he could be sent back to the White House as soon as Monday.

But Dr. Sean P. Conley said the president's condition had been worse than he previously admitted. Conley said Trump's blood oxygen levels had dropped in prior days and that he had run a high fever on Friday morning.

Asked what tests had revealed about the condition of Trump's lungs, Conley replied: "There's some expected findings, but nothing of any major clinical concern."

Conley's response suggested the X-rays revealed some signs of pneumonia, said Dr. Amesh Adalja, an infectious disease specialist at Johns Hopkins University.

"The expected finding is that he has evidence of pneumonia in the X-ray. If it was normal they would just say it is normal," Adalja said.

Donald Trump
Donald Trump leaves for Walter Reed National Military Medical Center YouTube Grab

'Wants to Appear in Control'

Trump wanted to show that he is in 'control' but was visibly 'weaker' during his fight with the coronavirus or COVID-19, a body language expert has said. The president gave an update about his health after getting treatment at the Walter Reed National Medical Center. He was wearing a white shirt with a blue suit and was surrounded by national flags as he sat at a polished desk. The body language expert Judi James stated that he tried to project that he is in control.

"There are several moments when Trump's signature hyperbole suggests he's in superhero mode. He insists 'I have to get back to make America great again', letting the country know that 'I have to finish that job'. He uses the word 'miracles' three times, adding that his 'therapeutics' are 'coming down from God' to raise the superhero notion," she told Mirror Online. Judi added that the president is clearly batting the deadly disease.

Downplaying Risks

Trump spent much of the year downplaying the risks of the COVID-19 pandemic, which has infected 7.4 million Americans, killed more than 209,000, and caused an economic downturn that has thrown millions out of work.

He said he had been meeting soldiers and first responders at the hospital, raising new questions about whether he was now directly exposing others to the disease.

Critics said personnel who traveled in Trump's armored SUV during the afternoon motorcade would now have to self-quarantine for 14 days. "The irresponsibility is astounding," Dr. James Phillips, an attending physician at the hospital, said on Twitter.

The White House Correspondents Association objected that reporters had not been told about Trump's drive-by before it happened.

White House spokesman Judd Deere said the trip had been approved by medical staff and that appropriate precautions had been taken.

Health officials in New Jersey said they were trying to track down more than 200 people who attended a Trump fundraising event at his golf course there on Thursday. Trump traveled to the event after close adviser Hope Hicks had contracted the virus, and just hours before he announced that he had tested positive.

White House spokeswoman Kayleigh McEnany said on Fox News that Trump tested positive after that fundraiser, not beforehand.

Trump's illness has upended his re-election campaign as it seeks to fend off Biden in the final month of the race. Several members of his inner circle have also tested positive for the disease, as well as three Republican members of the U.S. Senate.

Two members of the White House residence staff tested positive for COVID-19 a few weeks ago, and Trump's "body man" aide, Nicholas Luna, has also tested positive, according to a source familiar with the situation.