Objective: Early identification of COVID-19 in patients is important to prevent significant worsening of the disease. This study was undertaken to verify whether MEWS (Modified Early Warning Score), NEWS(National Early Warning Score), ROX index, and CURB-65, which are early diagnostic tools for severe respiratory diseases, could be applied to patients visiting the emergency room for COVID-19. Methods: This retrospective observational study included patients who visited an emergency medical center from September 1 to October 31, 2020, and from January 1 to February 28, 2021. Based on the vital signs and blood tests during the emergency room visit, severity evaluation tools and early diagnostic tools for severe cases were used and compared according to their area under the curve (AUC) values. The primary outcome was in-hospital mortality, while the secondary outcomes were intensive care unit admission rate and the need for mechanical ventilation based on these four tools (MEWS, NEWS, ROX index, and CURB-65). Results: A total of 667 patients were analyzed. No significant difference was determined between the non-survivor group and survivor group in the MEWS values (P=0.13), but statistically significant differences were observed for NEWS (5 vs. 1, P<0.05), CURB-65 (2 vs. 1, P<0.05), and ROX index (16.61 vs. 23.1, P<0.01). The AUC value of NEWS for death prediction indicated a good predictive power at 0.80, while that of MEWS showed a low predictive power at 0.57, which was statistically significant. Moreover, the AUC values of CURB-65 and ROX index did not differ significantly from values obtained for NEWS. Conclusion As early diagnostic tools for predicting death in COVID-19 patients, NEWS, ROX index, and CURB-65 showed excellent discrimination ability, whereas MEWS showed statistically and significantly lower discrimination ability.

Objective: This study examined the characteristics of patients visiting the emergency department (ED) with fever after the chronification of the coronavirus disease 2019 (COVID-19) pandemic. Methods: This retrospective observational study analyzed the medical records of patients who visited the ED with fever from May 1 to October 31, 2021, and the corresponding period in 2019. This study was conducted at a single center in Seoul, Korea. Results: There was no statistical difference in the comorbidities of the patients of the two groups: the AC (after the COVID-19 pandemic) group and the BC (before the COVID-19 pandemic) group. As for the level of consciousness at the time of ED arrival, there was a significantly larger decrease in consciousness (verbal response or less) in the AC group than in the BC group (P=0.002). In the case of the National Early Warning Score (NEWS), the proportion was higher in the AC group in the moderate-risk and high-risk groups (P=0.003). The median time from symptom onset to ED arrival was 15.7 hours in the BC group and 13.8 hours in the AC group, and there was no significant difference (P=0.137). When leaving the ED, the AC group had a higher admission rate to the ward and intensive care unit than the BC group. There was no statistical difference in the in-hospital mortality between the two groups (2.9% and 2.4%, respectively; P=0.62). Conclusion Patients who visited the emergency room with fever after one year of the COVID-19 pandemic showed a similar time from symptom onset to ED arrival compared to patients who visited before the COVID-19 pandemic. In addition, there was no difference in in-hospital mortality among these patients compared to those with fever before the COVID-19 pandemic.