By Jeff Mason WASHINGTON (Reuters) -President Joe Biden intends to nominate Surgeon General Vivek Murthy to be the U.S. representative on the World Health Organization’s executive board, administration officials told Reuters on Tuesday. Murthy has served as the top U.S. doctor under Biden and under former President Barack Obama. He will continue in that role while taking on the WHO position, if confirmed by the U.S. Senate. “With his experience and expertise, the president is confident that Dr. Murthy will build on his commitment to an era of relentless diplomacy by representing our nation on …