With equity markets already nervous about an uncertain presidential election in less than five weeks, analysts said the news had the potential to hurt Trump’s campaigning ability and jack up market volatility.

“If Trump’s symptoms are mild and he stages a quick recovery, his support could increase,” said Yako Sera, market strategist at Sumitomo Mitsui Trust Bank in Tokyo.

“However, this does damage Trump’s ability to campaign and time is running out before the election. Whether it’s Trump or Biden, the biggest problem is uncertainty. As long as we’re uncertain about who will win the election, it is difficult for markets to truly settle.”

Trading in US stocks was choppy in the previous session as investors juggled hopeful and pessimistic news on the progress of stimulus talks in Washington.

With a bipartisan deal continuing to elude House Speaker Nancy Pelosi and the White House, the US House of Representatives on Thursday approved a US$2.2 trillion Democratic plan on fiscal aid, but objections from top Republicans are likely to doom the plan in the Senate.

At 1:56am ET, Dow e-minis were down 432 points, or 1.56%, S&P 500 e-minis were down 52 points, or 1.54% and Nasdaq 100 e-minis were down 205.5 points, or 1.78%.