1. Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
2. Division of Clinical Microbiology, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
3. Division of Infectious Disease and International Medicine, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
4. Division of Infectious Disease, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA