1. Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
2. Division of Infectious Diseases, Dong-A University Hospital, Busan, Korea.
3. Division of Infectious Diseases, Konkuk University Medical Center, Seoul, Korea.
4. Division of Infectious Diseases, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea.