Funding for this research was provided by:
Received: 5 September 2018
Accepted: 13 February 2019
First Online: 5 March 2019
: JW Park is a medical doctor at Asan Medical Center, Department of Infectious Disease, and worked with epidemic investigation officer in KCDC.LH is medical doctor majored in preventive medicine and the government officer in division of Healthcare Associated Infection Control, KCDC.
: The study protocol was approved by the institutional review board of the KCDC (2018-04-01-PE-A), and the requirement for written informed consent from patients was waived.
: Not applicable.
: I declare that I have no significant competing financial, professional, or personal interests that might have influenced the performance or presentation of the work described in this manuscript.
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