Stocks, oil prices, and government bond yields all fell after South Africa issued a warning about a rapidly spreading strain of the coronavirus, raising fears that travel restrictions and other restrictions will stymie the global economy’s recovery.

Futures indicate that the S&P 500 will lose about 1.6 percent and the Dow Jones Industrial Average will lose about 2.2 percent when the U.S. stock market opens for a holiday-shortened trading session on Friday. Brent crude fell 5.3 percent to less than $77 a barrel, putting the global energy benchmark on track for its biggest one-day loss since July, as traders worried that movement restrictions would reduce demand for transportation fuels. Bitcoin fell 8.9 percent to less than $54,000.

Investors sought safe-haven assets, pushing 10-year Treasury note yields down to 1.537 percent from 1.644 percent before the Thanksgiving holiday. Yields, which move in the opposite direction of prices, had previously fallen to 1.505 percent, putting them on track for their biggest daily drop since the March 2020 market panic. Gold, another perceived store of value when riskier assets fall, increased more than 1% to $1,809 per troy ounce.

The sell-off caused a jolt in markets that had been anchored by concerns about the coronavirus to a large extent. Instead, investors have been preoccupied with the possibility that an overheating economy will cause runaway inflation, forcing the Federal Reserve and other central banks to raise interest rates.

Fears of a Coronavirus resurfaced in the market on Friday. Investors warned that the variant, dubbed B. 1.1.529, could jeopardize months of efforts to resurrect the global economy and save lives. According to scientists, the strain has a high number of mutations that may make it more transmissible and allow it to evade some of the immune responses triggered by previous infection or vaccination.

Investors bought shares in companies that stand to benefit from restrictions and sold shares in companies that stand to lose the most. Delta Air Lines, United Airlines, and American Airlines Group all fell 7% or more ahead of the opening bell after the United Kingdom, Israel, and Singapore restricted travel from southern Africa. The European Union has stated that it will propose a ban on air travel from the region. Royal Caribbean Group and other cruise companies were battered, while oil companies Exxon Mobil and Chevron both fell more than 4%.

Vaccine makers Moderna and Pfizer were among the winners in premarket trading, rising 8.3 percent and 5.6 percent, respectively. Netflix and DoorDash, which previously benefited from stay-at-home orders, rose 2.3 percent and 3.2 percent, respectively.

Traders braced for more volatility, though some speculated that Friday’s moves were exacerbated by low volumes following Thanksgiving. The Cboe Volatility Index, which measures expected swings in the S&P 500, was set to close at its highest level since September. Federal-fund futures showed traders cutting their bets on an interest-rate hike by the Fed’s June meeting to 64%, down from 82 percent on Wednesday.

Oil prices experienced some of the steepest drops. Traders said money managers were scrambling to unwind bets that a mismatch between tight supplies and rising demand would drive crude prices to $100 per barrel. The slump may persuade the Organization of Petroleum Exporting Countries and a group of Russia-led allies to postpone plans to increase oil production when they meet next week.

Money managers, according to oil traders, are rushing to unwind bets that a mismatch between tight supplies and rising demand would push crude prices above $100 per barrel. Traders said the price drop made it more likely that the Organization of Petroleum Exporting Countries and a group of Russia-led allies would put a halt to efforts to pump more oil when they met next week.

Money managers said that even if the variant proves to be more resistant to vaccines than previous strains, there are reasons to believe that the economic damage can be limited. mRNA vaccines, such as those produced by Pfizer and Moderna, can be rapidly updated, and businesses have adapted to containment measures, reducing the impact of each lockdown.

Friday saw a drop in international stock markets. Losses in travel, leisure, banking, and energy stocks, which all suffered during previous periods of economic turmoil during the pandemic, caused the Stoxx Europe 600 to fall 2.7 percent.