Donald Trump is back at the White House, dramatically returning from the military hospital where he was receiving an unprecedented level of care for Covid-19, igniting a new controversy by declaring that despite his illness the nation should not fear the virus that has killed more than 210,000 Americans — and then entering the executive mansion without a protective mask.

The president’s message alarmed infectious disease experts and suggested his own illness had not caused him to rethink his often-cavalier attitude towards the disease, which has also infected the first lady and several White House aides.

Landing on Monday night at the White House on Marine One, Mr Trump gingerly climbed the South Portico steps, removed his mask and declared: “I feel good.”

He gave a double thumbs-up to the departing helicopter from the portico terrace, where aides had arranged American flags for the occasion. He entered the White House, where aides were visible milling about in the Blue Room, without wearing a face covering.

The president left Walter Reed National Military Medical Centre, where his doctor, Navy Commander Sean Conley, said the president remained contagious and would not be fully “out of the woods” for another week, but that Mr Trump had met or exceeded standards for discharge from the hospital.

The president is expected to continue his recovery at the White House, where the reach of the outbreak that has infected the highest levels of the US government is still being uncovered.

A month before the election and anxious to project strength, Mr Trump tweeted on Tuesday morning that he was planning to attend next week’s debate with Democrat Joe Biden in Miami. “It will be great!” he said.

He also rushed out a new video from the White House, saying: “Don’t be afraid of it. You’re going to beat it. We have the best medical equipment, we have the best medicines.”

On Tuesday, he went a step further, repeating his previous comparisons between Covid-19 and the seasonal flu.

“Many people every year, sometimes over 100,000, and despite the Vaccine, die from the Flu,” he tweeted. “Are we going to close down our Country? No, we have learned to live with it, just like we are learning to live with Covid, in most populations far less lethal!!!”

Covid-19 has already proven to be a more potent killer, particularly among older populations, than seasonal flu, and has shown indications of having long-term impacts on the health of even younger people it infects.

Mr Trump’s nonchalant message came as his own administration encouraged Americans to be careful and take precautions to avoid contracting and spreading the disease as cases continue to spike across the country. For more than eight months, his efforts to play down the threat of the virus in hopes of propping up the economy ahead of the election have drawn bipartisan criticism.

President Donald Trump removes his mask as he stands on the balcony outside of the Blue Room as returns to the White House
President Donald Trump removes his mask as he stands on the balcony outside of the Blue Room as returns to the White House (Alex Brandon/AP)

“We have to be realistic in this: Covid is a complete threat to the American population,” said David Nace of the University of Pittsburgh Medical Centre.

“Most of the people aren’t so lucky as the president,” with an in-house medical unit and access to experimental treatments, added Dr Nace, an expert on infections in older adults.

“It’s an unconscionable message,” agreed Sadiya Khan of Northwestern University Feinberg School of Medicine. “I would go so far as to say that it may precipitate or worsen spread.”

Mr Biden, who spent more than 90 minutes on the debate stage with Mr Trump last week, said on Monday night that he was glad the president seemed to be recovering well, “but there’s a lot to be concerned about – 210,000 people have died. I hope no one walks away with the message that it’s not a problem”.

Mr Biden said he would “listen to the science” ahead of the upcoming debates, adding that the campaigns and the commission should be “very cautious” in making plans.

“If scientists say that it’s safe, that distances are safe, then I think that’s fine,” he said. “I’ll do whatever the experts say.”

Mr Trump’s arrival back at the White House raised new questions about how the administration was going to protect other officials from a disease that remains rampant in the president’s body.

Press secretary Kayleigh McEnany announced she had tested positive for the virus on Monday morning and was entering quarantine.

There were also lingering questions about potential long-term effects to the president — and even when he first came down with the virus.