Stocks gave up early gains and ended lower, extending their losses for the week.
Worries about economic fallout from the virus outbreak that originated in China has fueled a sharp sell-off that wiped out the market's gains for the year.
Energy stocks sank along with the price of oil. Cruise operators fell again, deepening a monthlong rout.
The bond market continued to flash warning signs as long-term yields fell further below short-term ones. The S&P 500 fell 11 points, or 0.4%, to 3,116. The Dow Jones Industrial Average fell 123 points, or 0.5%, to 26,957. The Nasdaq edged up 15 points, or 0.2%, to 8,980.