1. Infectious Control Office, Tao-Yuan General Hospital, Ministry of Health and Welfare, Taoyuan, Taiwan.
2. Department of Laboratory Medicine, Tao-Yuan General Hospital, Ministry of Health and Welfare, Taoyuan, Taiwan.
3. Department of Laboratory Medicine, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.
4. Department of Medical Laboratory, Chang Gung Memorial Hospital, Linkou, Taoyuan, Taiwan.
5. Department of Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan.