Staff at the Centers for Disease Control and Prevention tell ABC News the agency has descended into turmoil as senior officials offer their resignations over the Trump administration's effort to oust the agency's new director. A dozen CDC staffers, speaking on the condition of anonymity, described the mood inside the agency to ABC News, including some who said Thursday that the last 24 hours have left them questioning how much longer they should remain in their roles amid fears that the agency is, in the words of one staffer, "changing from a trusted scientific organization to a personal dictatorship" run...