Coronavirus Disease Outbreak in Call Center, South Korea - Volume 26, Number 8—August 2020 - Emerging Infectious Diseases journal - CDC

Coronavirus Disease Outbreak in Call Center, South Korea - Volume 26, Number 8—August 2020 - Emerging Infectious Diseases journal - CDC

Volume 26, Number 8—August 2020

Synopsis

Coronavirus Disease Outbreak in Call Center, South Korea

Shin Young Park, Young-Man Kim, Seonju Yi, Sangeun Lee, Baeg-Ju Na, Chang Bo Kim, Jung-il Kim, Hea Sook Kim, Young Bok Kim, Yoojin Park, In Sil Huh, Hye Kyung Kim, Hyung Jun Yoon, Hanaram Jang, Kyungnam Kim, Yeonhwa Chang, Inhye Kim, Hyeyoung Lee, Jin Gwack, Seong Sun Kim, Miyoung Kim, Sanghui Kweon, Young June Choe, Ok Park, Young Joon Park, and Eun Kyeong Jeong 

Author affiliations: Korea Centers for Disease Control and Prevention, Cheongju, South Korea (S.Y. Park, Y.-M. Kim, S. Yi, S. Lee, H. Lee, J. Gwack, S.S. Kim, M. Kim, S. Kweon, O. Park, Y.J. Park, E.K. Jeong); Seoul Metropolitan Government, Seoul, South Korea (B.-J. Na, J.-i. Kim, H.S. Kim, Y.B. Kim); Seoul Health Foundation, Seoul (C.B. Kim); Seoul Center for Infectious Disease Control and Prevention, Seoul (Y. Park, I.S. Huh); Incheon Metropolitan City, Incheon, South Korea (H.K. Kim, H.J. Yoon, H. Jang); Gyeonggi Provincial Office, Suwon, South Korea (K. Kim, Y. Chang, I. Kim); Hallym University College of Medicine, Chuncheon, South Korea (Y.J. Choe)

Cite This Article

Abstract

We describe the epidemiology of a coronavirus disease (COVID-19) outbreak in a call center in South Korea. We obtained information on demographic characteristics by using standardized epidemiologic investigation forms. We performed descriptive analyses and reported the results as frequencies and proportions for categoric variables. Of 1,143 persons who were tested for COVID-19, a total of 97 (8.5%, 95% CI 7.0%–10.3%) had confirmed cases. Of these, 94 were working in an 11th-floor call center with 216 employees, translating to an attack rate of 43.5% (95% CI 36.9%–50.4%). The household secondary attack rate among symptomatic case-patients was 16.2% (95% CI 11.6%– 22.0%). Of the 97 persons with confirmed COVID-19, only 4 (1.9%) remained asymptomatic within 14 days of quarantine, and none of their household contacts acquired secondary infections. Extensive contact tracing, testing all contacts, and early quarantine blocked further transmission and might be effective for containing rapid outbreaks in crowded work settings.

Since the first imported case of coronavirus disease (COVID-19) was confirmed in South Korea on January 20, 2020, a sharp increase in the number of COVID-19 cases has been observed, with most infections being reported from specific clusters (1). Outbreaks of COVID-19 related to mass gathering, religious activities, workplaces, and hospitals have accounted for the largest portion cases in the national outbreak (1).

In March 2020, the Korea Centers for Disease Control and Prevention (KCDC), South Korea’s national-level public health authority, was informed about a cluster of cases of COVID-19 in a call center located in a commercial–residential mixed-use building (building X) in the capital city of Seoul. We describe the epidemiology of this COVID-19 outbreak and detail the containment efforts to limit the spread of the disease.