1. Division of Clinical Microbiology, Mayo Clinic, Rochester, MN, USA
2. Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
3. Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
4. Department of Infectious Diseases, University Hospital Heidelberg, Heidelberg, Germany
5. Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA