To determine factors associated with delayed discharge of hospitalized patients with coronavirus disease (COVID-19). This retrospective cohort study included 47 patients with COVID-19 admitted to three hospitals in Quanzhou City, Fujian Province, China, between January 21, 2020 and March 6, 2020. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with delayed discharge. The median length of hospital stay was 22 days. Patients in the delayed discharge group (length of hospital stay ≥ 21 days, n = 27) were more likely to have diarrhea, anorexia, decreased white blood cell counts, increased complement C3 and C-reactive protein levels, air bronchograms, undergo thymalfasin treatment, and take significantly longer to convert to a severe acute respiratory syndrome coronavirus (SARS-CoV-2) RNA-negative status than those in the control group (length of hospital stay, < 21 days; n = 20). In multivariate logistic regression analysis, the time to SARS-CoV-2 RNA-negative conversion (odds ratio [OR]: 1.48, 95% confidence interval [CI] 1.09–2.04, P = 0.01) and complement C3 levels (OR 1.14 95% CI 1.02–1.27, P = 0.03) were the only risk factors independently associated with delayed discharge from the hospital. Dynamic monitoring of complement C3 and SARS-CoV-2 RNA levels is useful for predicting delayed discharge of patients.

This study aimed to investigate the clinical features of patients infected with novel coronavirus wild strains, Delta variant strains and Omicron variant strains to provide a reference for early clinical diagnosis and prognostic assessment. The demographic, clinical symptoms and ancillary examination data of 47 patients with novel coronavirus wild type strain infection, 18 with Delta variant infection and 20 with Omicron variant infection admitted to the First Hospital of Quanzhou affiliated with Fujian Medical University were collected and analyzed. The novel coronavirus wild strain and Delta strain were the predominant clinical types; patients infected with the Omicron strain were mainly asymptomatic. Fever and fatigue were the main clinical manifestations in the wild strain and Delta strain groups, whereas dry cough, nasal congestion, sore throat and fever were common clinical manifestations in the Omicron strain group. The Delta strain and Omicron variant groups had fewer comorbidities than the wild-type strain group, but no significant reduction was observed in the negative conversion time of nucleic acids. Significant differences were found in the neutrophil count/lymphocyte count ratio, lymphocyte count, eosinophil count, red blood cell count, hemoglobin level, erythrocyte sedimentation rate, C-reactive protein, prothrombin time, international normalized ratio and plasma D-dimer, PH, PaO 2 , lactic acid and albumin levels among the three groups. Patients infected with the Omicron strain in Quanzhou presented with mild symptoms of the upper respiratory tract as the primary clinical manifestation and had few comorbidities and a good prognosis; however, the negative conversion time of the new coronavirus nucleic acid was still considerably long.

HLA polymorphism is hypothesized to be associated with diverse immune responses towards infectious diseases. Herein, by comparing against multiple subpopulation groups as control, we confirmed that HLA-B*15:27 and HLA-DRB1*04:06 were associated with COVID-19 susceptibility in China. Both alleles were predicted to have weak binding affinities towards viral proteins.