Stocks fall as fears about deadly virus grow; Dow drops 170

Stocks are closing with broad losses as increased fears that an outbreak of a deadly virus could spread more widely rattles markets. The S&P 500 had its worst day since early October as health care stocks incurred steep losses. The sell-off followed news that a Chicago woman has become the second U.S. patient diagnosed with the new virus from China. The S&P 500 index fell 0.9%. The Dow Jones Industrial Average dropped 170 points, or 0.6%, to 28,989. The Nasdaq lost 0.9%. The yield on the 10-year Treasury fell to 1.69% from 1.74% Thursday.