Support WBURCDC Director: 'Very Aggressive' Contact Tracing Needed For U.S. To Return To NormalPlay04:27Download AudioSelena Simmons-DuffinRob SteinApril 10, 2020 ShareRobert Redfield, director of the Centers for Disease Control and Prevention, spoke with NPR on Thursday, saying that his agency is working on a plan to safely reopen the United States. (CQ-Roll Call Inc. via Getty Images)