1. Department of Medicine, School of Medicine and
2. State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Health, National Centre for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong Province, China;
3. Department of Molecular Microbiology and Immunology, Brown University, Providence, Rhode Island;
4. College of Science, University of Notre Dame, South Bend, Indiana;
5. Department of Medicine-M.D. Program, San Juan Bautista School of Medicine, Caguas, Puerto Rico;
6. Department of Pathology, Children's Hospital Colorado, Aurora, Colorado;
7. Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania; and
8. Department of Pediatrics, University of Colorado Anschutz Medical Center, Aurora, Colorado;
9. Department of Epidemiology, Colorado School of Public Health, Aurora, Colorado