1. From the Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore (M.E.D., K.M.N.), the Center for Infectious Diseases Research, Walter Reed Army Institute of Research, Silver Spring (N.L.M.), and the Henry Jackson Foundation, Bethesda (M.R.) — all in Maryland; and the Institute for Global Health and Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill (M.S.C.).