1. Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
2. School of MedicineNational Yang-Ming University, Taipei 112, Taiwan
3. Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan 736, Taiwan
4. College of MedicineFu Jen Catholic University, New Taipei City 242, Taiwan
5. Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Medical University HospitalKaohsiung Medical University, Kaohsiung 807, Taiwan
6. Section of Infectious Diseases, Department of Internal Medicine, Changhua Christian Hospital, Changhua 500, Taiwan
7. Institute of Emergency and Critical Care MedicineNational Yang-Ming University, Taipei 112, Taiwan
8. Division of Infectious Diseases, Department of Internal Medicine, China Medical University HospitalChina Medical University, Taichung 404, Taiwan
9. Department of Biological Science and Technology, College of Biological Science and TechnologyNational Chiao Tung University, HsinChu 300, Taiwan