US President Donald Trump, who is in the hospital with Covid-19 infection, received supplemental oxygen on Sunday and is now being treated with a potent steroid amid indications that his lungs may have suffered some damage, the White House physician said.

Iran PressAmerica: At a briefing in front of Walter Reed National Military Medical Centre outside Washington, doctors treating Trump continued to be upbeat about his condition. One of his physicians said the president could be discharged as soon as Tuesday, but another conceded they had not been entirely forthcoming in their initial medical briefing.

Significantly, Conley said the president had been given dexamethasone, a steroid.

The disclosure that Trump is receiving dexamethasone is a clear signal that his illness is a serious one, said Ashish Jha, dean of the Brown University School of Public Health. In an interview, Jha said he would watch for the use of dexamethasone, which would be an "apparent signal that he has a more severe disease."

Meanwhile, President Donald Trump on Sunday briefly left his hospital room at Walter Reed National Military Medical Center, where he is being treated for Covid-19, to drive past a group of supporters, a move medical experts and Democrats swiftly criticized as "insanity."

The unannounced trip sparked a backlash from several prominent Democratic lawmakers and some doctors not involved in his care, who accused Trump of unnecessarily putting Secret Service agents at risk.

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