Background: This study evaluated the safety and effectiveness of the cytomegalovirus (CMV) Specific Antigen Induced Interferon-Gamma ELISPOT (enzyme-linked immunosorbent spot)/ELISA (enzyme-linked immunosorbent assay) procedure in predicting the risk of CMV infection/disease in immunocompromised patients through a systematic literature review. Methods: The searched electronic databases included MEDLINE, EMBASE and the Cochrane Library. A total of 884 non-duplicate citations were retrieved and a total of 25 studies (15 cohort studies, 10 cross-sectional studies) were included in this review. Study subjects were selected among patients with solid organ, hematopoietic stem cell transplantation, or those who were on hemodialysis. Data extraction and literature quality assessment were carried out independently by two researchers. Results: Most of the studies were conducted on patients with solid organ transplants. As it is conducted outside the body, CMV Specific Antigen Induced Interferon-Gamma ELISPOT/ELISA assay was safe. Regarding its effectiveness, most studies on risk analysis based on prognosisrelated outcomes reported that the inactive group showed a significantly higher hazard ratio or odds ratio than the active group. Results of Kaplan-Meier survival analysis also showed that the inactive group had a significantly higher incidence of CMV event (CMV infection, CMV disease, other events) than the active group. However, various thresholds for CMV cell immune response were reported, as was a broad range of predictive diagnostic accuracies. Conclusion CMV Specific Antigen Induced Interferon-Gamma ELISPOT/ELISA assay has potential to stratify the risk of CMV infection/disease among solid organ transplant patients and to determine a policy for a prophylaxis/preemptive. However, additional literature evidence is needed to establish thresholds for CMV cell immune response and standardized tests.

Background: This study evaluated the safety and effectiveness of the cytomegalovirus (CMV) Specific Antigen Induced Interferon-Gamma ELISPOT (enzyme-linked immunosorbent spot)/ELISA (enzyme-linked immunosorbent assay) procedure in predicting the risk of CMV infection/disease in immunocompromised patients through a systematic literature review. Methods: The searched electronic databases included MEDLINE, EMBASE and the Cochrane Library. A total of 884 non-duplicate citations were retrieved and a total of 25 studies (15 cohort studies, 10 cross-sectional studies) were included in this review. Study subjects were selected among patients with solid organ, hematopoietic stem cell transplantation, or those who were on hemodialysis. Data extraction and literature quality assessment were carried out independently by two researchers. Results: Most of the studies were conducted on patients with solid organ transplants. As it is conducted outside the body, CMV Specific Antigen Induced Interferon-Gamma ELISPOT/ELISA assay was safe. Regarding its effectiveness, most studies on risk analysis based on prognosisrelated outcomes reported that the inactive group showed a significantly higher hazard ratio or odds ratio than the active group. Results of Kaplan-Meier survival analysis also showed that the inactive group had a significantly higher incidence of CMV event (CMV infection, CMV disease, other events) than the active group. However, various thresholds for CMV cell immune response were reported, as was a broad range of predictive diagnostic accuracies. Conclusion CMV Specific Antigen Induced Interferon-Gamma ELISPOT/ELISA assay has potential to stratify the risk of CMV infection/disease among solid organ transplant patients and to determine a policy for a prophylaxis/preemptive. However, additional literature evidence is needed to establish thresholds for CMV cell immune response and standardized tests.

In 2017, the Korean government launched an unprecedentedly large-scaled latent tuberculosis infection (LTBI) screening project which covered more than a million individuals in congregate settings. A total of 1,047,689 participants of source population (n = 2,336,157) underwent LTBI testing from 2017 to 2018. The overall LTBI test uptake rate during this project was 44.8%. Workers in daycare centers (83.5%) and kindergartens (78.9%) showed high participation rate. A total of 1,012,206 individuals with valid results of interferongamma release assay (IGRA) were selected to constitute the IGRA cohort. Most of the enrolled participants in the IGRA cohort were in their working age. Approximately, threequarters of total enrolled population were female. Investigating the LTBI prevalence, stages of LTBI care cascade, natural history of LTBI, efficacy of LTBI treatment and cost-effectiveness of LTBI screening are feasible within this IGRA cohort.

In 2017, the Korean government launched an unprecedentedly large-scaled latent tuberculosis infection (LTBI) screening project which covered more than a million individuals in congregate settings. A total of 1,047,689 participants of source population (n = 2,336,157) underwent LTBI testing from 2017 to 2018. The overall LTBI test uptake rate during this project was 44.8%. Workers in daycare centers (83.5%) and kindergartens (78.9%) showed high participation rate. A total of 1,012,206 individuals with valid results of interferongamma release assay (IGRA) were selected to constitute the IGRA cohort. Most of the enrolled participants in the IGRA cohort were in their working age. Approximately, threequarters of total enrolled population were female. Investigating the LTBI prevalence, stages of LTBI care cascade, natural history of LTBI, efficacy of LTBI treatment and cost-effectiveness of LTBI screening are feasible within this IGRA cohort.

Background: In February 2020, a coronavirus disease 2019 (COVID-19) outbreak was reported in fitness centers in Cheonan, Korea. Methods: From February 24 to March 13, an epidemiological investigation was conducted on the fitness center outbreak. All those who were screened were tested for severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) using real-time reverse transcriptase polymerase chain reaction. Contacts were traced and self-isolated for 14 days. We determined the epidemiological characteristics of confirmed cases of SARS-CoV-2 infection, and estimated the time-dependent reproduction number to assess the transmission dynamics of the infection. Results: A total of 116 cases were confirmed, and 1,687 contacts were traced. The source cases were 8 Zumba instructors who led aerobics classes in 10 fitness centers, and had the largest average number of contacts. A total of 57 Zumba class participants, 37 of their family members, and 14 other contacts were confirmed as cases. The attack rate was 7.3%. The contacts at Zumba classes and homes had a higher attack rate than other contacts. The mean serial interval (± standard deviation) were estimated to be 5.2 (± 3.8) days. The time-dependent reproduction number was estimated to be 6.1 at the beginning of the outbreak, but it dropped to less than 1, 2 days after the epidemiological investigation was launched. Conclusion The results suggest that the COVID-19 outbreak was effectively contained with rigorous contact tracing, isolating, and testing in combination with social distancing without a lock-down.