1. Division of Infectious Diseases, Departments of Microbiology and Immunology and Medicine, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
2. Departments of Pediatrics and of Pathology, Microbiology, and Immunology and Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
3. Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
4. Department of Microbiology and Molecular Genetics, University of California Irvine, California, USA
5. Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA