1. Department of Internal Medicine, Division of Infectious Diseases, Mayo Clinic, Rochester, Minnesota.
2. Department of Internal Medicine, Section of Infectious Diseases, Rush University Medical Center, Chicago, Illinois.
3. Department of Orthopaedic Surgery, Rothman Institute at Thomas Jefferson University, Philadelphia, Pennsylvania.
4. Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia. (Currently Del Mar, California.)