Table 3.
Number of COVID-19 clusters (with case numbers range) by type from January to September 2020 in the Seoul metropolitan area. Types of clusters: type I – small size <30 cases, short duration <2 weeks; type II – small size <30 cases, long duration ≥ 2 weeks; type III – medium size 30–99 cases, long duration ≥2 weeks; and type IV – large size ≥100 cases, long duration ≥2 weeks.
| Type I | Type II | Type III | Type IV | |
|---|---|---|---|---|
| Church | 15 (5–17) | 14 (5–30) | 7 (34–51) | 2 (205–1010) |
| Workplace | 21 (5–20) | 10 (8–31) | 4 (36–87) | 1 (163) |
| Protest | NA | NA | NA | 1 (249) |
| Night clubs | NA | NA | NA | 1 (177) |
| Network marketing services | 2 (10–12) | NA | NA | 1 (163) |
| Family/friends | 13 (5–16) | 4 (6–21) | 1 (29) | NA |
| Health training center | 3 (8–16) | 1 (12) | 1 (49) | NA |
| Apartment | 1 (6) | 2 (13–19) | 1 (36) | NA |
| Restaurant | 2 (8–9) | NA | 2 (30–58) | NA |
| Shop | 1 (6) | NA | 1 (75) | NA |
| Club activities | NA | 3 (15–26) | NA | NA |
| School | 1 (5) | 2 (15–32) | NA | NA |
| Public/private academy | 1 (10) | 2 (22–35) | NA | NA |
| Meeting | 1 (8) | 2 (23–25) | NA | NA |
| Hair salon | NA | 1 (11) | NA | NA |
| Buddhist conference | 1 (22) | NA | NA | NA |
| Guest house | 1 (6) | NA | NA | NA |
| Military unit | 1 (16) | NA | NA | NA |
| Nursery center | 4 (6–17) | NA | NA | NA |
| Police station | 1 (7) | NA | NA | NA |
| Sauna | 1 (19) | NA | NA | NA |