1. Infection Control Department, Dankook University Hospital, Cheonan, Korea
2. Infection Control Office, Korea University Guro Hospital, Seoul, Korea
3. Department of Nursing Science, Sun Moon University, Asan, Korea
4. Infection Control Office, Ewha Womans University Mokdong Hospital, Seoul, Korea
5. Infection Control Office, Seoul National University Bundang Hospital, Seongnam, Korea
6. Center for Infection Prevention and Control, Samsung Medical Center, Seoul, Korea
7. Infection Control Team, Chungang University Hospital, Seoul, Korea