The president’s physician, Dr. Sean Conley, said in a memo to reporters that he received confirmation of the positive tests on Thursday evening US time. Conley said Trump and Melanie are both well at this stage, and that they will stay in the White House during their quarantine. Trump will continue carrying out duties while recovering “without disruption,” according to the memo.

Vice president Mike Pence sent his wishes for a speedy recovery to the president and first lady, but didn’t say if he had been tested or what the results were. Pence is next in line to run the administration if Trump were unable to do so.

Even before the news, investors expected a contested election, but also that the uncertainty would be wrapped up by the January 2021 inauguration. On Friday, global stocks fell and the VIX Index, also known as the fear gauge, rose about 8%.

Hicks, who is one of the president’s closest advisers, was confirmed to have the virus on Thursday evening. She has traveled with the president multiple times recently, including to the first US presidential election debate in Cleveland, Ohio, on Tuesday. Several other close aides of Trump and at least one relative, son-in-law Jared Kushner, have also traveled with Hicks this week.

The news casts even more uncertainty over the upcoming presidential election in November. Both 74-year-old Trump and his rival, 77-year-old Democratic nominee Joe Biden, who was in the same room with him for the debate, fall in the high-risk category for a severe case of the infection. For starters, voters will likely pay far closer attention to the vice-presidential debate between Mike Pence and Democrat Kamala Harris next week.

A lot will depend on what happens with the president’s health between now and the election. Congress does have the power to delay the election if it deems it necessary—say for example in the case of the grave illness of a president who’s also a candidate. But it would be unprecedented: Even during the Civil War America voted as scheduled.

Trump is not the only leader to have contracted Covid-19. UK prime minister Boris Johnson had it earlier this year and spent three nights in intensive care, while Brazil’s Jair Bolsonaro contracted it in July.

During the pandemic, the US president has often downplayed the severity of the epidemic or the need for social restrictions or the need to use masks, including this week when he mocked Biden for his frequent mask use. A Cornell study of coronavirus misinformation released yesterday (Oct. 1) said that Trump was a surprisingly strong driver of falsehoods about the illness, including touting unverified cures.

The US handling of the pandemic has drawn consternation globally as it became the country most affected by the disease. More than 7 million Americans have contracted the coronavirus, and more than 200,000 have died of it.

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