1Division of Epidemiological Investigation Analysis, Bureau of Public Health Emergency Preparedness Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
2Team of Epidemiological Investigation, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
3Department of Infectious Disease Control, Bureau of Health & Sports, Incheon Metropolitan Government, Incheon, Republic of Korea
4Division of Emerging Infectious Diseases, Bureau of Infectious Disease Diagnosis Control, Korea Disease Control and Prevention Agency, Cheongju, Republic of Korea
5Department of Building Research, Korea Institute of Civil Engineering and Building Technology, Goyang, Republic of Korea
© 2024 Korea Disease Control and Prevention Agency.
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Ethics Approval
This study was reviewed and approved by the Institutional Review Board of the KDCA (No: KDCA-2023-05-04-PE-01) and was performed in accordance with the principles of the Declaration of Helsinki. Due to the retrospective nature of the study, the requirement for informed consent was waived.
Conflicts of Interest
The authors have no conflicts of interest to declare.
Funding
This investigation was conducted as part of a primary initiative of the Center for Epidemiological Investigation and Analysis at the KDCA. The name of this initiative is “Reinforcement of epidemiological investigation capacity and establishment of a research base” (grant No: 6231-3335-210-01).
Availability of Data
The SARS-CoV-2 whole-genome sequences have been submitted to the Global Initiative on Sharing All Influenza Data (GISAID) EpiCoV database (http://gisaid.org). The GISAID accession IDs for these sequences can be found in Supplementary Material 1.
Authors’ Contributions
Conceptualization: HYL, YJP, SEL; Data curation: HNY, IHK, JSN; Formal analysis: HYL, YJP; Funding acquisition: MY, SEL; Investigation: HNY, HYL, YJP, JY, SB, IHK, JSN, MY; Methodology: HYL, YJP, SEL, JY, SB, IHK, EJK; Project administration: YJP, SEL; Resources: YJP, SEL, EJK; Software: HYL, IHK, JSN; Supervision: YJP, SEL, EJK; Visualization: HYL, IHK, JSN; Writing–original draft: HYL, YJP; Writing–review & editing: all authors. All authors read and approved the final manuscript.
Acknowledgements
The authors thank the movie theater for its cooperation in field epidemiological investigations and the evaluation of ventilation conditions. In addition, we would like to thank the COVID-19 managers at the local public health clinics in Incheon Metropolitan City for their efforts to respond to COVID-19.
Characteristic | Confirmed case |
---|---|
Total | 48 (100.0) |
Sex | |
Male | 30 (62.5) |
Female | 18 (37.5) |
Age (y) | |
≤19 | 10 (20.8) |
20–29 | 21 (43.8) |
30–39 | 3 (6.3) |
40–49 | 6 (12.5) |
50–59 | 1 (2.1) |
60–69 | 4 (8.3) |
≥70 | 3 (6.3) |
Classification | |
Third screening audience | 28 (58.3) |
Fourth screening audience | 7 (14.6) |
Fifth screening audience | 0 (0.0) |
Theater staff | 1 (2.1) |
Family member | 10 (20.8) |
Friend | 2 (4.2) |
Symptoms | |
Asymptomatic | 10 (20.8) |
Symptomatic | 38 (79.2) |
Vaccination status | |
Unvaccinated or first vaccination | 13 (27.1) |
Second vaccination | 35 (72.9) |
Place of exposure | |
Movie theater | 36 (75.0) |
House | 10 (20.8) |
Elementary school | 1 (2.1) |
Othera) | 1 (2.1) |
Characteristic | Total | Confirmed cases | Attack rate | Crude risk ratioa) | Adjusted risk ratiob) |
---|---|---|---|---|---|
Total | 80 (100.0)c) | 35 (100.0) | 43.8 (33.4–54.7) | ||
Sex | |||||
Male | 51 (63.8) | 22 (62.9) | 43.1 (30.5–56.7) | Ref. | Ref. |
Female | 29 (36.3) | 13 (37.1) | 44.8 (28.4–62.5) | 1.1 (0.42–2.69) | 1.7 (0.54–5.60) |
Age (y) | |||||
≤18 | 15 (18.8) | 8 (22.9) | 53.3 (30.1–75.2) | Ref. | Ref. |
>19 | 65 (81.3) | 27 (77.1) | 41.5 (30.4–53.7) | 0.6 (0.20–1.93) | 1.0 (0.17–7.13) |
Screening attended | |||||
Third | 33 (41.3) | 28 (80.0) | 84.8 (69.1–93.3) | 24.0 (7.4–93.8) | NA |
Fourth | 37 (46.3) | 7 (20.0) | 18.9 (9.5–34.2) | Ref. | Ref. |
Fifth | 10 (12.5) | 0 (0.0) | 0.0 (0.0–27.8) | NA | NA |
Food consumption | |||||
No | 74 (92.5) | 29 (82.9) | 39.2 (28.9–50.6) | Ref. | Ref. |
Yes | 6 (7.5) | 6 (17.1) | 100.0 (61.0–100.0) | NA | NA |
Vaccination status | |||||
Unvaccinated or first vaccination | 10 (12.5) | 7 (20.0) | 70.0 (39.7–89.2) | Ref. | Ref. |
Second vaccination | 70 (87.5) | 28 (80.0) | 40.0 (29.3–51.7) | 0.4 (0.09–1.42) | 0.2 (0.02–1.26) |
Proximity of exposure | |||||
Casual contact | 61 (76.3) | 19 (54.3) | 31.1 (20.9–43.6) | Ref. | Ref. |
Close contact | 19 (23.8) | 16 (45.7) | 84.2 (62.4–94.5) | 11.8 (3.44–55.17) | 15.9 (4.37–78.39) |
Data are presented as n (%) or % (95% confidence interval).
Ref., reference; NA, not available.
a)The univariable model was adjusted for matching factors, including sex, age, screening attended, food consumption, vaccination status, and proximity of exposure.
b)The multivariable model was adjusted for all variables incorporated within it, with the exceptions of screening attended and food consumption.
c)A total of 12 people were excluded from the study: 1 individual in the 3rd screening, 5 in the 4th screening, and 6 in the 5th screening.
Characteristic | Confirmed case |
---|---|
Total | 48 (100.0) |
Sex | |
Male | 30 (62.5) |
Female | 18 (37.5) |
Age (y) | |
≤19 | 10 (20.8) |
20–29 | 21 (43.8) |
30–39 | 3 (6.3) |
40–49 | 6 (12.5) |
50–59 | 1 (2.1) |
60–69 | 4 (8.3) |
≥70 | 3 (6.3) |
Classification | |
Third screening audience | 28 (58.3) |
Fourth screening audience | 7 (14.6) |
Fifth screening audience | 0 (0.0) |
Theater staff | 1 (2.1) |
Family member | 10 (20.8) |
Friend | 2 (4.2) |
Symptoms | |
Asymptomatic | 10 (20.8) |
Symptomatic | 38 (79.2) |
Vaccination status | |
Unvaccinated or first vaccination | 13 (27.1) |
Second vaccination | 35 (72.9) |
Place of exposure | |
Movie theater | 36 (75.0) |
House | 10 (20.8) |
Elementary school | 1 (2.1) |
Other |
1 (2.1) |
Characteristic | Total | Confirmed cases | Attack rate | Crude risk ratio |
Adjusted risk ratio |
---|---|---|---|---|---|
Total | 80 (100.0) |
35 (100.0) | 43.8 (33.4–54.7) | ||
Sex | |||||
Male | 51 (63.8) | 22 (62.9) | 43.1 (30.5–56.7) | Ref. | Ref. |
Female | 29 (36.3) | 13 (37.1) | 44.8 (28.4–62.5) | 1.1 (0.42–2.69) | 1.7 (0.54–5.60) |
Age (y) | |||||
≤18 | 15 (18.8) | 8 (22.9) | 53.3 (30.1–75.2) | Ref. | Ref. |
>19 | 65 (81.3) | 27 (77.1) | 41.5 (30.4–53.7) | 0.6 (0.20–1.93) | 1.0 (0.17–7.13) |
Screening attended | |||||
Third | 33 (41.3) | 28 (80.0) | 84.8 (69.1–93.3) | 24.0 (7.4–93.8) | NA |
Fourth | 37 (46.3) | 7 (20.0) | 18.9 (9.5–34.2) | Ref. | Ref. |
Fifth | 10 (12.5) | 0 (0.0) | 0.0 (0.0–27.8) | NA | NA |
Food consumption | |||||
No | 74 (92.5) | 29 (82.9) | 39.2 (28.9–50.6) | Ref. | Ref. |
Yes | 6 (7.5) | 6 (17.1) | 100.0 (61.0–100.0) | NA | NA |
Vaccination status | |||||
Unvaccinated or first vaccination | 10 (12.5) | 7 (20.0) | 70.0 (39.7–89.2) | Ref. | Ref. |
Second vaccination | 70 (87.5) | 28 (80.0) | 40.0 (29.3–51.7) | 0.4 (0.09–1.42) | 0.2 (0.02–1.26) |
Proximity of exposure | |||||
Casual contact | 61 (76.3) | 19 (54.3) | 31.1 (20.9–43.6) | Ref. | Ref. |
Close contact | 19 (23.8) | 16 (45.7) | 84.2 (62.4–94.5) | 11.8 (3.44–55.17) | 15.9 (4.37–78.39) |
Data are presented as Department store.
Data are presented as Ref., reference; NA, not available. The univariable model was adjusted for matching factors, including sex, age, screening attended, food consumption, vaccination status, and proximity of exposure. The multivariable model was adjusted for all variables incorporated within it, with the exceptions of screening attended and food consumption. A total of 12 people were excluded from the study: 1 individual in the 3rd screening, 5 in the 4th screening, and 6 in the 5th screening.