OBJECTIVE  To analyze the epidemiological subtyping of the novel coronavirus Omicron variant and its clinical characteristics in patients from a hospital in Xinjiang, providing references for precise prevention and clinical intervention.

METHODS  Whole-genome sequencing data and clinical records of 581 novel coronavirus-infected patients admitted to the First Affiliated Hospital of Xinjiang Medical University from Jan. 2024 to Dec. 2024 were collected. Strain subtyping was performed with the Pangolin and Nextclade databases, and logistic regression models were employed to assess risk factors for severe disease.

RESULTS  The Omicron variant was predominantly composed of JN.1 (63.34%), XDV.1 (15.83%) and KP1.1 (5.51%), with a phased shift in epidemiological trends: BA.2.86 and its sublineages dominated from Jan. to Aug. (accounting for 62.07%−97.96%), while the XDV.1 sublineages became predominant from Sep. to Dec. (accounting for 50.00%−76.92%). The BA.2.86 group exhibited significantly higher rates of cough with sputum (43.10%, P＜0.001), fever (41.90%, P＜0.001) and ICU admission (33.81%) than other groups. Multivariate analysis identified BA.2.86 strain (OR=3.320, 95%CI: 1.577−6.989, P=0.002), BB strain typing (OR=2.332, 95%CI: 1.030−5.279, P=0.043), age (OR=1.116, 95%CI: 1.013−1.333, P=0.032), cough and expectoration (OR=2.117, 95%CI: 1.403−3.195, P＜0.001), fever (OR=1.857, 95%CI: 1.282−2.690, P=0.001), diabetes (OR=1.651, 95%CI: 1.052−2.592, P=0.029) and cardiovascular and cerebrovascular diseases (OR=1.974, 95%CI: 1.208−3.224, P=0.006) as risk factors for severe novel coronavirus Omicron infection.

CONCLUSIONS  The prevalence of Omicron sublineages demonstrates dynamic evolution. The BA.2.86 strain is associated with higher respiratory symptoms and severe disease risk, while advanced age and underlying conditions significantly worsen clinical outcomes. Monitoring and treatment strategies should be optimized for high-risk strains and patients with complications.