B. Frank Polk was appointed to revive the Division of Infectious Disease in the Department of Epidemiology. Polk becomes a leader in AIDS research, evaluating and improving the sensitivity of HIV blood tests, essential for controlling the AIDS epidemic. Under Polk, JHSPH is selected as one of five sites in the Multicenter AIDS Cohort Study (MACS), which becomes the longest-running AIDS research study in history. This research has contributed significantly to treatment and prevention. Pictured, John Bartlett examining AIDS patient at Johns Hopkins Hospital, Moore Clinic.