1. Department of Molecular Biomedical Sciences; North Carolina State University; Raleigh NC 27606
2. Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health; Bethesda MD 20892
3. Departments of Pediatrics and Microbiology and Immunology and Elizabeth B. Lamb Center for Pediatric Research; Vanderbilt University School of Medicine; Nashville TN 37232