1. Department of Preventive Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Epidemiology & Case Management Team, COVID-19 National Emergency Response Center, Korea Centers for Disease Control and Prevention, Cheongju, Korea.
3. Chungnam Center for Infectious Diseases Control and Prevention, Hongseong, Korea.
4. Seosan Public Health Center, Seosan, Korea.
5. Department of Preventive Medicine, College of Medicine, Dankook University, Cheonan, Korea.