Received: 7 May 2020
Accepted: 16 August 2020
First Online: 24 August 2020
Ethics approval and consent to participate
: The Korea Centers for Disease Control and Prevention (KCDC) has the authority to hold and analyze surveillance data for public health and research purposes. KCDC approved the data use and provided data without personal identification information.
: Not applicable.
: All authors declare that they have no competing interest.