Dr. Robert Redfield, the director of the C.D.C., confirmed in an interview with WABE in Atlanta, a National Public Radio member station, on Monday that the agency was reviewing its guidelines on who should wear masks. Citing new data that shows high rates of transmission from people who are infected but show no symptoms, he said the guidance on mask wearing was “being critically re-reviewed, to see if there’s potential additional value for individuals that are infected or individuals that may be asymptomatically infected.”