SARS-CoV-2 Breakthrough Infections after introduction of 4 COVID-19 Vaccines, South Korea, 2021.

We conducted a nationwide retrospective cohort study to estimate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) breakthrough infection among recipients of 4 different vaccines in South Korea. Age-adjusted breakthrough infection rate per month was highest for Janssen (42.6/100,000 population), followed by AstraZeneca (21.7/100,000 population), Pfizer-BioNTech (8.5/100,000 population), and Moderna (1.8/100,000 population).

Impact of COVID-19 on human immunodeficiency virus tests, new diagnoses, and healthcare visits in the Republic of Korea: a retrospective study from 2016 to 2021.

BACKGROUND: Public health workers have been at the forefront of treating patients with coronavirus disease 2019 (COVID-19) and managing the pandemic. The redeployment of this workforce has limited or interrupted other public health services, including testing for human immunodeficiency virus (HIV). This study aims to examine the impact of COVID-19 on HIV testing and diagnosis in the Republic of Korea from 2016 to 2021, comparing data before and after the onset of COVID-19. METHODS: Annual HIV testing data were collected from each institution through direct communication or from open-source databases. The annual number of new HIV cases was obtained from the official report of the Korea Disease Control and Prevention Agency. Data on healthcare visits for HIV diagnosis or treatment were extracted from the open-source database of the National Insurance Health Service of Korea. Interrupted time series regression was conducted, stratified by institution type. RESULTS: In 2020, HIV tests, diagnoses, and visits decreased. Notably, public health centers experienced a substantial reduction in 2020-2021 compared to previous years. The annual percentage change in HIV tests was -53.0%, while for HIV diagnoses, it was -31.6%. The decrease in visits for HIV was also most pronounced for public facilities: -33.3% in 2020 and -45.6% in 2021 relative to 2019. CONCLUSION: The numbers of tests, diagnoses, and healthcare visits for HIV at public health centers in the Republic of Korea substantially decreased in 2020 and 2021. The impacts of these changes on the early diagnosis and treatment of HIV necessitate further monitoring.

Tracing the Untraceables: A Joint Outbreak Investigation With Law Enforcement Using a Geographic Information System.

The application of geospatial data often allows the tracing of people who are involved in activities of an illegal nature. In June 2021, we estimated the true magnitude of the spread of COVID-19 within the networks of escort-karaoke bars in Seoul, Republic of Korea, using geographic information system (GIS)-based contact tracing that was applied to our epidemiological investigation. Our joint rapid response team, composed of epidemic investigation officers and police personnel, identified 19 paper-traced cases and 158 GIS-traced cases from 5,692 confirmed cases in Seoul during the study period (June to July 2021). Our findings suggest that collaboration with law enforcement agencies and the use of overlaid satellite imagery in outbreak investigations enhances high vigilance and reduces the risk of potential breaches of human rights in the process.

Detecting mpox infection in the early epidemic: an epidemiologic investigation of the third and fourth cases in Korea.

OBJECTIVES: As few mpox cases have been reported in Korea, we aimed to identify the characteristics of mpox infection by describing our epidemiologic investigation of a woman patient (index patient, the third case in Korea) and a physician who was infected by a needlestick injury (the fourth case). METHODS: We conducted contact tracing and exposure risk evaluation through interviews with these 2 patients and their physicians and contacts, as well as field investigations at each facility visited by the patients during their symptomatic periods. We then classified contacts into 3 levels according to their exposure risk and managed them to minimize further transmission by recommending quarantine and vaccination for post-exposure prophylaxis and monitoring their symptoms. RESULTS: The index patient had sexual contact with a man foreigner during a trip to Dubai, which was considered the probable route of transmission. In total, 27 healthcare-associated contacts across 7 healthcare facilities and 9 community contacts were identified. These contacts were classified into high (7 contacts), medium (9 contacts), and low (20 contacts) exposure risk groups. One high-risk contact was identified as a secondary patient: a physician who was injured while collecting specimens from the index patient. CONCLUSIONS: The index patient visited several medical facilities due to progressive symptoms prior to isolation. Although the 2022 mpox epidemic mainly affected young men, especially men who have sex with men, physicians should also consider mpox transmission in the general population for the timely detection of mpox-infected patients.

COVID-19 outbreak and risk factors for infection in a taekwondo gym in the Republic of Korea.

OBJECTIVES: Relatively few studies have assessed risk factors for coronavirus disease 2019 (COVID-19) in public facilities used by children and adolescents. This study presents an analysis of a COVID-19 outbreak that occurred in a taekwondo gym in Korea, predominantly among children and adolescents, with the aim of providing insights on managing COVID-19 outbreaks in similar facilities. METHODS: All 108 taekwondo gym students and staff received COVID-19 tests. A survey and closed-circuit television analyses were used to identify risk factors. A univariate analysis was conducted, followed by multivariate logistic regression analysis with backward elimination for variables with a significance level <0.10 in the univariate analysis. RESULTS: COVID-19 was confirmed in 30 of 108 subjects at the taekwondo gym (attack rate, 27.8%). The outbreak started in an adult class student. This student transmitted the virus to the staff, who consequently transmitted the virus to adolescent students. In the univariate analysis, the relative risk for younger age (≤9 years) was 2.14 (95% confidence interval [CI], 1.01-4.54; p=0.054), and that for food consumption inside the gym was 2.12 (95% CI, 1.04-4.30; p=0.048). In the multivariate logistic regression analysis, the odds ratio for younger age was 2.96 (95% CI, 1.07-8.20; p=0.036), and that for food consumption inside the gym was 3.00 (95% CI, 1.10-8.17; p=0.032). CONCLUSION: Food consumption inside the facility and young age were significant risk factors for COVID-19 transmission in this taekwondo gym. Food consumption should be prohibited in sports facilities, and infection prevention education for young students is also required.