We analyzed reports for 59,073 contacts of 5,706 coronavirus disease (COVID-19) index patients reported in South Korea during January 20-March 27, 2020. Of 10,592 household contacts, 11.8% had COVID-19. Of 48,481 nonhousehold contacts, 1.9% had COVID-19. Use of personal protective measures and social distancing reduces the likelihood of transmission.
Keywords: 2019 novel coronavirus disease; COVID-19; SARS-CoV-2; South Korea; contact tracing; coronavirus disease; pneumonia; respiratory diseases; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.