From May to July 2015, the Republic of Korea experienced the largest outbreak of MERS outside the Arabian Peninsula. As of September 30, 2015, 16,693 individuals had been quarantined, 186 individuals were confirmed to be infected with MERS-CoV, and re...
From May to July 2015, the Republic of Korea experienced the largest outbreak of MERS outside the Arabian Peninsula. As of September 30, 2015, 16,693 individuals had been quarantined, 186 individuals were confirmed to be infected with MERS-CoV, and related deaths totaled 36. We aimed to determine the clinical features and outcomes of Korean patients confirmed to be infected with MERS-CoV, and the risk factors contributing to mortality. We performed a retrospective observational study focusing on the clinical characteristics and outcomes of confirmed cases of MERS-CoV infection in Korea. Patient information was collected using a standardized case-report form. The median age of the patients was 55 years (range, 16 to 86). A total of 55.4% of the patients had one or more coexisting medical conditions. Hypertension (31.7%), diabetes (18.8%), and solid organ malignancy (13.4%) were most common. The most common symptom was fever (95.2%). At admission, leukopenia (42.6%), thrombocytopenia (46.6%), and elevation of aspartate aminotransferase (42.7%) were observed relatively often. Abnormalities in chest radiography were detected in 68.3% of patients at admission. Antiviral agents were used for 74.5% of patients. Mechanical ventilation, extracorporeal membrane oxygenation (ECMO), and convalescent serum were employed for 24.5%, 7.1%, and 3.8% of patients, respectively. Thirty-six patients (19.4%) died in hospital. Older age, symptom of dyspnea, presence of coexisting medical conditions including diabetes or chronic lung disease, hypotension, leukocytosis, and the use of mechanical ventilation were revealed to be independent predictors of death. Among severe patients with mechanical ventilation, the non-survivors were older, had chronic lung disease or solid organ malignancy more frequently, had elevated serum creatinine more frequently, and received ECMO or convalescent serum less frequently. The clinical features of MERS-CoV infection in the Republic of Korea were similar to those of previous outbreaks in the Middle East. However, the overall mortality rate was lower than in previous reports. Enhanced surveillance and active management of patients during the outbreak may have resulted in improved outcomes.