1. Infectious Disease Clinical Research Program, Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland.
2. The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, Maryland.
3. Walter Reed National Military Medical Center, Bethesda, Maryland.
4. San Antonio Military Medical Center, JBSA Fort Sam Houston, Texas.
5. Westat, Rockville, Maryland.
6. Landstuhl Regional Medical Center, Landstuhl, Germany.