1. Department of Virology III
2. Laboratory of Molecular Growth Regulation, Genomics of Differentiation Program, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892-2753
3. Department of Bacterial Pathogenesis and Infection Control, National Institute of Infectious Diseases, Tokyo 208-0011, Japan
4. Integrated Research Facility, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
5. Population and Public Health Branch, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Manitoba R3E 3R2, Canada