Background:We aimed to identify the problems in response and to present the importance of infection control in nursing homes (NHs) through an epidemiological analysis of the first and second COVID-19 outbreaks in Gyeonggi province. Methods:We reviewed the NH's structural and operational data and in-depth epidemiologic reports for confirmed cases that were obtained as part of an emergency public health response.Results: Two COVID-19 outbreaks in NHs stemmed from infected nursing home workers (NHWs), and cohorting measures were implemented as a method of infection control. However, the outcome of cohorting was unfavorable due to the unexpected spread to NHWs wearing personal protective equipment (PPE) during work. As a result, the majority of confirmed cases was nursing home residents with a median age of 86, and they accounted for 72% and 60% of confirmed cases in NH A and NH B, respectively. Moreover, all cases of mortality were nursing home residents, and the case-fatality rates were 44.44% and 33.33%, respectively. Conclusion:We confirmed that NHs and NHWs were closely involved in the process and outcomes of outbreaks. Enhanced infection control techniques for NHs and NHWs should be mandatory to prevent further transmission in addition to external factors such as social measures and medical supplies.

(1) Background and Objectives: There were two distinct coronavirus disease 2019 (COVID-19) outbreaks in 2020 and 2022 at a long-term mental health facility (LTMHF) in Gyeonggi Province, Korea. We aimed to compare the two outbreaks and identify differences in epidemiological and clinical outcomes due to changes in epidemic timing and management methods. (2) Materials and Methods: The structural, operational, and case-specific LTMHF data of COVID-19-confirmed patients during these outbreaks in 2020 and 2022 were retrospectively analyzed. (3) Results: Forty individuals (37 residents) in 2020 and thirty-nine (32 residents) in 2022 were confirmed to have COVID-19, and ten were infected twice. Facility isolation was implemented as an infection control measure, and one COVID-19-related death occurred in 2020. All residents and staff were vaccinated at least twice in 2022; moreover, in 2022, 38 patients (97.4%) received a third vaccination less than months before infection. The average Ct value of the cases in 2022 was significantly higher than that in 2020; however, vaccine-breakthrough (V-BT) and reinfection after vaccination rates were similar. (4) Conclusions: COVID-19 vaccination could help lower the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was inversely correlated with Ct values, and ventilation system improvements in health facilities might reduce transmissibility.