Photo: AP Photo/Ted S. Warren, File.
FILE - In this March 16, 2020, file photo, Neal Browning receives a shot in the first-stage safety study clinical trial of a potential vaccine for COVID-19, the disease caused by the new coronavirus, at the Kaiser Permanente Washington Health Research Institute in Seattle. The vaccine by Cambridge, Massachusetts-based Moderna Inc., generated antibodies similar to those seen in people who have recovered from COVID-19 in a study of volunteers who were given either a low or medium dose.