NEW YORK (Reuters) – World stock markets gave up early gains as a continued flight from healthcare shares dragged on Wall Street, overshadowing upbeat economic data from China.

The S&P 500 dipped as the healthcare index dived 3.4% to erase its year-to-date gains on continued fallout from concerns about potential changes to U.S. policy, including a “Medicare for All” proposal by Senator Bernie Sanders.

“With a Democrat-controlled Congress, there is definitely more talk on regulating the sector and drug prices, which has negative headline risks,” said Matthew Granfki, director of strategy at Los Angeles-based Miracle Mile Advisors.

Mixed corporate results, including a revenue miss from International Business Machines Corp, also contributed to Wall Street’s stall, said Stephen Massocca, senior vice president at Wedbush Securities in