UnitedHealth Group, the worst-performing stock in the Dow Jones Industrial Average so far this year, got a major boost last week from billionaire investor Warren Buffett. Berkshire Hathaway Buffett’s investment group, disclosed it had bought 5 million shares of the healthcare company earlier in the year. Investors eager to follow in the Sage of Omaha’s footsteps need to be wary of a few risks, according to Bank of America analyst Kevin Fishbeck.
