Abstract:Objective To analyze the clinical characteristics and treatment of 330 patients with novel coronavirus disease 2019(COVID-19) in Yuncheng City to provide some reference for clinical decision-making. Methods A retrospective analysis was performed on the the data of 330 patients with COVID-19 treated in Yuncheng designated hospitals from October 7 to November 10, 2022.There were 157 cases of asymptomatic infections, 145 cases of mild infections, 17 cases of common infections and 11 cases of severe infections. The general information, clinical characteristics and treatment of patients were observed and compared. Results Compared with the patients with asymptomatic infections, mild infections and common infections, the patients with severe infection were older, with 100% of them having underlying diseases and a higher proportion of malignant tumors, with the statistical differences in them(P＜0.05）.The vaccination rates were respectively 36.4% in severe patients, 77.1% in asymptomatic patients, 81.4% in mild patients and 88.2% in common patients, and there were the significant differences in it among the different types of patients(P＜0.05). In severe patients, the lymphocyte count and the absolute CD4+T lymphocyte counts significantly decreased, and the levels of C-reactive protein and D-dimer increased significantly compared with those in other types of patients(P＜0.05). The proportion of severe patients without medication was the lowest, and the proportion of application of thymalfasin and nimatevir/ritonavir and convalescent plasma were the highest during rehabilitation. Conclusion The persons without underlying diseases are more likely to be infected with mild and asymptomatic infection of COVID-19. Older age and malignant tumors are the high risk factors of severe COVID-19, which needs to be treated with antiviral drugs combined with Chinese medicine and immuno-enhancing drugs. Lymphocyte level, CD4+T lymphocyte absolute count, CRP and D-dimer may be related to the severity of COVID-19 infection. Vaccination can produce protective antibody IgG and is an effective measure to reduce the severe infection of COVID-19.