Global markets dropped early Friday after President Trump said that he and the first lady had tested positive for the coronavirus.
Futures markets that track stocks in the United States signaled that Wall Street would open more than 1.5 percent lower.
European futures suggested markets there would open similarly lower. Yields on United States Treasury bonds fell too, as did futures tracking crude oil prices.
The news throws the political leadership of the world’s largest economy into doubt. It also raises questions about his campaign for re-election against former Vice President Joseph R. Biden Jr., his Democratic challenger. The election is set for Nov. 3, a little more than a month away.
In Japan, where the news broke late on the trading day, stocks were nearly 0.7 percent lower after spending most of the day in positive territory. Most other Asian markets were closed for autumn holidays.