1. Division of Infectious Diseases; Department of Internal Medicine; Korea University College of Medicine; Seoul Korea
2. Department of Biostatistics; Korea University College of Medicine; Seoul Korea
3. Division of Infectious Diseases; Department of Internal Medicine; Hallym University College of Medicine; Chuncheon Korea
4. Division of Infectious Diseases; Department of Internal Medicine; College of Medicine, The Catholic University of Korea; Seoul Korea
5. Division of Infectious Diseases and Infection Control Unit; Department of Internal Medicine; Inha University School of Medicine; Incheon Korea