Since the first case of coronavirus disease19 (COVID-19) was reported in Wuhan, China, as of March 2, 2020, the total number of confirmed cases of COVID-19 was 89,069 cases in 67 countries and regions. As of 0 am, March 2, 2020, the Republic of Korea had the second-largest number of confirmed cases (n = 4,212) after China (n = 80,026). This report summarizes the epidemiologic features and the snapshots of the outbreak in the Republic of Korea from January 19 and March 2, 2020.

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Report on the Epidemiological Features of Coronavirus Disease 2019 (COVID-19) Outbreak in the Republic of Korea from January 19 to March 2, 2020

Go to: TIMELINE OF COVID-19 OUTBREAK IN KOREA Fig. 1A shows the timeline of significant events in Korea since January 19, 2020, when the first confirmed case with Chinese nationality entered Korea from Wuhan, China.1, 2 Since the first case, the sources of infection could be traced by contact investigation until the patient 29. The patient 29 was the first patient identified in Seoul and did not have an epidemiological link or travel history to China. From this patient, the possibility of community transmission was raised. The first pediatric case (patient 32) was diagnosed on February 18, 2020.3 The first fatal case occurred on February 20, 2020. As the numbers of confirmed cases were rapidly increasing, the Korean government raised the alert level from orange to red on February 23 and the Ministry of Education delayed the new school year opening by one week on February 23, 2020 and currently ordered all school closures. As of February 29, 76 countries banned Koreans from entering their countries.4

Fig. 1

Timeline of COVID-19. (A) Whole country of Republic of Korea. (B) Religious group in Daegu and Gyeongsangbuk-do. (C) Hospital exposure in Eunpyeong St. Mary's Hospital and the Korea University Anam Hospital emergency room in Seoul.

Patient 31 was the first case related to the religious group. Daenam Hospital has a mental ward where many casualties occurred. ROK = Republic of Korea, Pt = patient, COVID-19 = Coronavirus disease-19, KCDC = Korea Centers for Disease Control and Prevention, WHO = World Health Organization, PHEIC = Public Health Emergency of International Concern, PCR = polymerase chain reaction, ER = emergency room, sx = symptom. Click for larger image Download as PowerPoint slide

Laboratory test for COVID-19 was initially performed at the Korea Centers for Disease Control and Prevention (KCDC) and the test became available at 17 regional laboratories (Public Health and Environment Research Institute) on January 24 throughout the nation.5 Since February 7, the test facilities were expanded to 46 laboratories including tertiary hospitals6 and more test centers were added later. Fig. 1B shows the timeline of the events related to a religious group called Shincheonji that contributed to the explosive outbreak in the city of Daegu and Gyeongsangbuk-do (North Gyeongsang Province). On January 27, 2020, a brother of the leader of this religious group was hospitalized in Daenam Hospital in Cheongdo, a town which is 27 km from Daegu. His brother died on January 31, and they had a funeral ceremony for two nights and three days from January 31 to February 2 in a hospital funeral home located in Daenam Hospital. Because this was the funeral service of the leader's family, many members (about 170) of the religious group visited the hospital funeral home for 3 days. A 61-year-old woman from this religious group who visited the funeral was later confirmed with COVID-9 on February 23. Of note, she lived in Daegu and occasionally commuted to Seoul. Tracing her movements, KCDC found that she attended two worship services at the Shincheonji Church in Daegu with at least 1,000 other members of her religious group. Fig. 1C shows the timeline of the confirmed case in a patient transporter who worked at the Eunpyeong St. Mary's Hospital with over 800 beds located in northern Seoul. A 35-year-old man developed symptoms of COVID-19 on February 2 and transported several patients from February 2 to February 17 before he quit his job at the hospital. A total of 302 were identified as his contacts and out of 262 patients he transported, 187 patients have already discharged from the hospital and 75 patients were still in the hospital.7 As a result, the hospital has been closed and 14 additional patients were confirmed from this hospital as of March 2, 2020.

Go to: PEDIATRIC POPULATION The proportion of children (≤ 19 years) is 18% of the total population of Korea.12 Therefore, COVID-19 in this age group also needs attention. Since the diagnosis of the first pediatric case on February 19, 2020,3 the number of pediatric cases (≤ 19 years) gradually increased and 201 children were confirmed with COVID-19 as of March 2, 2020. The first pediatric case in Korea was a 10-year old girl who was exposed sequentially to the confirmed family members (a relative and her mother). Fig. 3 shows the cumulative pediatric cases from February 10 to March 2, 2020. The proportion of pediatric cases (≤ 19 years) was 4.8% of total confirmed cases (32 children in 0–9 years old age group, 169 children in 10–19 years old age group).8 Among all pediatric cases (≤ 19 years), the proportion of younger children (0–9 years old) was 15.9%. Of note, there was a 4-year old boy who attended the daycare center before the confirmation. Identifying the transmission pattern in young children requires more data.13 As of March 2, the youngest pediatric case with COVID-19 in Korea was a 45-day old male baby who was infected by his father, a member of the religious group. Most pediatric patients are in mild clinical conditions.

Fig. 3

Cumulative pediatric cases in the Republic of Korea as of March 2, 2020.

aThe child was presumed to have been infected by a familial exposure. He attended the daycare center one day before the symptom onset; bThe youngest pediatric case as of March 2, 2020. Click for larger image Download as PowerPoint slide

More detailed data are required on the clinical manifestation of the children and the roles of infected children on the epidemiology of COVID-19 in the community.