US president Donald Trump and first lady Melania have tested positive for coronavirus and will go into quarantine, the US president tweeted late on Thursday evening hours after one of his most senior advisers, Hope Hicks, was reported to have contracted the infection. Hicks had travelled with the president on multiple trips this week including abroad Marine One, the presidential helicopter, and Air Force One. It isn’t immediately clear how Trump contracted the virus that has infected over 7 million Americans and killed more than 200,000.

Trump announced his health status on Twitter, saying they will “begin our quarantine and recovery process immediately. We will get through this TOGETHER!,” he said.

Within minutes of Trump’s announcement, Bloomberg reported U.S. stock futures fell more than 1 per cent and 0il prices extended losses to drop around 2 per cent early Friday. 

New agency Reuters said Trump had kept up a rigorous travel schedule across the country in recent weeks, holding rallies with thousands of people in the run-up to the Nov. 3 election, despite warnings from public health professionals against having events with large crowds.

Trump had a packed schedule for Friday too including a private fund-raiser at the Trump International Hotel in Washington, a campaign rally in Florida and a call with “vulnerable seniors” about the disease, the New York Times reported.

The infection would impact Trump’s ability to campaign in person for the presidential elections. There is no clarity from his office if he will continue to address events over video but his new schedule just lists a midday phone call on “Covid-19 support to vulnerable seniors.”

Watch: Donald Trump, Melania start ‘quarantine process’ after aide tests Covid positive

The president’s physician Sean Conley said Donald Trump and Melania “are both well at this time, and they plan to remain at home within the White House during their convalescence”.

“Rest assured, I expect the President to continue carrying out his duties without disruption while recovering,” Dr Conley said in a statement.

White House spokesman Judd Deere said contact tracing for Trump and Melania Trump was being carried out. Bloomberg said the 74-year-old president’s positive result was likely to sharpen an already intense public attention on his handling of the pandemic as he campaigns for re-election against Democrat Joe Biden, who leads in national polls.