President Donald Trump’s decision to greet supporters in a drive-past outside the hospital where he is being treated for Covid-19 has been widely questioned by medical experts.

There are concerns the president, who wore a mask, may have endangered Secret Service staff inside the car.

However, White House spokesperson Judd Deere said the trip on October 4 had been “cleared by the medical team as safe”.

Questions remain over the seriousness of President Trump’s illness after conflicting statements over the weekend.

Donald Trump has been in hospital since October 2, after he announced hours earlier he had tested positive for the virus.

Covid-19 has infected n

Nearly 7.4 million have been infected in the US and nearly 210,000 people died across the country, according to Johns Hopkins University.

President Trump’s diagnosis has upended his election campaign, as he faces Democratic challenger Joe Biden on November 3.

A growing number of people around the president, including First Lady Melania Trump, senior aides and Republican senators, have tested positive with the virus.

President Trump waved to well-wishers from behind the glass of a sealed car after tweeting that he would leave Walter Reed hospital, near Washington, to pay a “surprise visit” to “patriots” outside. Inside the car, at least two people could be seen wearing protective gear in the front seats, with President Trump sat in the back.

Experts say Donald Trump’s short car trip broke public health advice to quarantine when seeking treatment for the virus, and may have put Secret Service agents inside the vehicle at risk of infection.

“That Presidential SUV is not only bulletproof, but hermetically sealed against chemical attack. The risk of Covid-19 transmission inside is as high as it gets outside of medical procedures,” tweeted Dr James Philips, a doctor at the same hospital where the president is being treated.

Those inside the president’s car would now need to quarantine for 14 days, he said.

President Trump Flown to Walter Reed Army Medical Center

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Democrats have also criticized the trip, with House of Representatives Hakeem Jeffries tweeting: “We need leadership. Not photo ops.”

However, the White House’s Judd Deere defended the move, saying “appropriate precautions were taken in the execution of this movement to protect the president and all those supporting it, including PPE [personal protective equipment]”. Meanwhile, NBC News reports that the first lady, who has remained at the White House with mild symptoms, decided against visiting her husband in hospital because of the risks to staff.

“She has Covid,” an unnamed official told NBC on October 3.

“That would expose the agents who would drive her there and the medical staff who would walk her up to him.”

Over the weekend it emerged President Trump’s condition was more serious than previously reported when he went to hospital on October 2.

The White House had said the president was experiencing “mild symptoms” of Covid-19, but then it was confirmed that he had received extra oxygen after his levels dipped twice in two days.

He was also given the steroid dexamethasone, which is normally reserved for serious cases, according to experts.

On October 4, White House Physician Dr. Sean Conley addressed widespread confusion over the state of President Trump’s health, after conflicting accounts from him and the president’s chief of staff, Mark Meadows.

Dr. Sean Conley had offered an upbeat prognosis on October 3, which was later contradicted by Mark Meadows who said the president’s vital signs the previous 24 hours had been “very concerning”.

Dr. Conley told reporters on October 4: “I was trying to reflect an upbeat attitude of the team and the president about the course his illness has had.

“I didn’t want to give any information that might steer the course of illness in another direction.”

There is skepticism over the prospect – raised by doctors earlier – that President Trump could leave hospital as early as October 5.