1. Group Health Research Institute, Seattle, Washington
2. Division of Infectious Disease and Tropical Pediatrics, Department of Pediatrics, Center for Vaccine Development, University of Maryland School of Medicine, Baltimore
3. Division of Infectious Diseases, Allergy, and Immunology, Saint Louis University School of Medicine, St Louis, Missouri
4. Vanderbilt Vaccine Research Program, Vanderbilt University Medical Center, Nashville, Tennessee
5. Departments of Molecular Virology and Microbiology and Medicine, Baylor College of Medicine, Houston, Texas
6. The EMMES Corporation, Rockville, Maryland
7. Southern Research Institute, Birmingham, Alabama