1. Division of Clinical Research, National Health Research Institute, Taipei 11529, Taiwan.
2. Division of Infectious Disease and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
3. Sections of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital and National Yang-Ming University, Taipei, Taiwan.
4. Department of Internal Medicine, Kaohsiung Medical University Hospital Taiwan, Taipei, Taiwan.