1. College of Public Health, University of Iowa, Iowa City, Iowa, USA
2. Departments of Medicine and Pathology & Laboratory Medicine, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, USA
3. Division of Infectious Diseases, University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
4. Division of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, Massachusetts, USA