WASHINGTON (AP) — Stricken by COVID-19, a feverish and fatigued President Donald Trump was flown to a military hospital Friday night after being injected with an experimental drug combination in treatment at the White House.

In a day of whipsaw events, the president who has spent months downplaying the threat of the virus was forced to cancel all campaign events a month before the election as he fought a virus that has killed more than 205,000 Americans and is hitting others in his orbit as well.

The White House said Trump’s expected stay of “a few days” at Walter Reed National Military Medical Center was precautionary and that he would continue to work from the hospital’s presidential suite, which is equipped to allow him to keep up his official duties.

Trump walked out of the White House Friday evening wearing a mask and gave a thumbs-up to reporters but did not speak before boarding Marine One. Members of the aircrew, Secret Service agents and White House staff wore face coverings to protect themselves from the president on board the helicopter.

In a videotaped before leaving for Walter Reed, Trump said, “I think I’m doing very well, but we’re going to make sure that things work out.” He remained fully president, all authority intact.

Just a month before the presidential election, Trump’s revelation that he was positive for the virus came by tweet about 1 a.m. Friday after he had returned from a Thursday afternoon political fundraiser. He had gone ahead to the event, saying nothing to the crowd though knowing he had been exposed to an aide with the disease that has infected millions in America and killed more than a million worldwide.

First lady Melania Trump also tested positive, the president said, and several others in the White House have, too, prompting concern that the White House or even Trump himself might have spread the virus further. He said in his video that his wife was doing very well.

Several administration officials pointed to the Saturday Rose Garden announcement of Trump’s nomination of Judge Amy Coney Barrett to the Supreme Court as the possible connection between cases that spanned Washington Friday. Former White House counselor Kellyanne Conway, the president of the University of Notre Dame, and at least two Republican lawmakers who were also present at the event — Utah Sen. Mike Lee and North Carolina Sen. Thom Tillis — announced Friday they had tested positive and were isolating.

Trump’s diagnosis came during an already turbulent period in Washington and around the world, with the U.S. gripped in a heated presidential election amid the human and economic toll of the virus. Trump’s immediate campaign events were all canceled, and his next debate with Democrat Joe Biden, scheduled for Oct. 15, is now in question.

Trump has been trying all year — and as recently as Wednesday — to convince the American public that the worst of the pandemic is past, and he has consistently played down concerns about being personally vulnerable. He has mostly refused to abide by basic public health guidelines — including those issued by his own administration — such as wearing face coverings in public and practicing social distancing. Until he tested positive, he continued to hold campaign rallies that drew thousands of often maskless supporters.

“I felt no vulnerability whatsoever,” he told reporters back in May. With the election coming up in about a month, he is urging states and cities to “reopen” and reduce or eliminate shutdown rules despite continuing virus outbreaks.

The White House tried to maintain an atmosphere of business-as-usual on Friday.

“President Trump remains in good spirts, has mild symptoms, and has been working throughout the day,” said press secretary Kayleigh McEnany. “Out of an abundance of caution, and at the recommendation of his physician and medical experts, the president will be working from the presidential offices at Walter Reed for the next few days.”