1. Department of Preventive Medicine, Dongguk University College of Medicine, Gyeongsangbuk-do, South Korea.
2. Division of Epidemic Intelligence Service, Korea Centers for Disease Control and Prevention, Chungcheongbuk-do, South Korea.
3. Division of Microbiology, Incheon Research Institute of Public Health and Environment, Incheon, South Korea.
4. Division of Enteric Bacterial Infections, Center for Infectious Diseases, Korea National Institute of Health, Chungcheongbuk-do, South Korea.
5. Korea Centers for Disease Control and Prevention, Chungcheongbuk-do, South Korea.