标题：上海市松江区方舱医院678例新型冠状病毒Omicron BA.2变异株感染病例的临床特征

      作者：沈华，刘依萌，盛阮妹，吴怡文，王学敏    南京医科大学上海松江临床医学院急诊危重病科，上海 201600

      卷次： 2023年34卷4期

      【摘要】 目的 分析感染新型冠状病毒(SARS-CoV-2) Omicron BA.2变异株病例的临床特征，为OmicronBA.2感染的防治提供参考依据。方法 回顾性分析 2022年 4月 3日至 4月 18日上海市松江区方舱医院收治的678例新型冠状病毒感染确诊患者的临床特征，同时根据临床分型分为无症状组 369例和轻型组 309例，比较两组患者的临床特征、疫苗接种及转阴时间。结果 患者平均年龄为(36.11±13.20)岁，呈低龄化趋势，主要集中在15~44岁组(73.9%)，其次为 45~59岁组(18.7%)，≥60岁组(4.7%)及 0~14岁组(2.7%)占比较少；患有慢性基础疾病者 19例(2.8%)，主要为高血压及糖尿病；总体疫苗接种率为 94.5%，15~44岁组(97.6%)及 45~59岁组(95.3%)接种率最高，≥60岁组(81.2%)次之，接种率最低为0~14岁组(27.8%)；轻症组患者平均核酸转阴时间为(11.44±2.36) d，明显长于无症状组的(10.80±2.22) d，差异具有统计学意义(P<0.05)；两组患者在性别、年龄、疫苗接种针数及完成疫苗接种至确诊感染的间隔天数方面比较差异均无统计学意义(P>0.05)；生存分析结果显示，无症状组患者的转阴风险较轻型组患者高28.1% (HR=1.281，95%CI：1.100~1.492，P=0.001)，但进一步亚组分析，在不同性别、年龄段及疫苗接种亚组中，两组患者预后比较差异均无统计学意义(P>0.05)；在轻型组患者中，临床症状以干咳(68.0%)、发热(29.1%)最为多见，COX单因素分析结果显示，是否出现相关临床症状并非影响轻型患者转阴预后的影响因素(P>0.05)。结论 SARS-CoV-2 Omicron BA.2在不同性别及年龄段人群中具有普遍易感性，感染呈现低龄化趋势，感染者以呼吸道症状与发热为主要表现，核酸转阴天数与原始毒株相似，无症状感染者较轻型患者可能具有更短的病程。
      【关键词】 新型冠状病毒肺炎；新型冠状病毒；OmicronBA.2变异株；临床特征；生存分析
      【中图分类号】 R511 【文献标识码】 A 【文章编号】 1003—6350（2023）04—0541—05

Clinical characteristics of 678 patients with SARS-CoV-2 Omicron BA.2 variant infection in Shanghai SongjiangDistrict Mobile Cabin Hospital.
SHEN Hua, LIU Yi-meng, SHENG Ruan-mei, WU Yi-wen, WANG Xue-min.Department of Emergency ＆ Critical Care, Shanghai Songjiang Clinical Medical College of Nanjing Medical University,Shanghai 201600, CHINA
【Abstract】 Objective To analyze the clinical characteristics of cases infected with the novel coronavirus(SARS-CoV-2) Omicron BA.2 variant and to provide a reference basis for the prevention and treatment of OmicronBA.2 infection cases. Methods This retrospective study included patients with SARS-CoV-2 infection in ShanghaiSongjiang District Mobile Cabin Hospital from April 3 to April 18 in 2022. Patients who met the diagnostic criteria forcommon COVID-19 were enrolled (678 cases) and were divided into the asymptomatic group (369 cases) and mildgroup (309 cases) according to their clinical symptoms. Clinical characteristics, vaccination status, and negative conver-sion time of SARS-CoV-2 RNA were evaluated in two groups. Results Mean age of the patients enrolled was (36.11±13.20) years, with the obvious trend of lower age. The patients mainly distributed in the 15-44 years group (73.9%), fol-lowed by the 45-59 years group (18.7%), with a smaller proportion in the ≥60 years group (4.7%) and the 0-14 yearsgroup (2.7%). There were 19 cases (2.8%) with chronic underlying diseases, mainly hypertension and diabetes. The over-all vaccination rate was 94.5% , with the highest rates in the 15-44 years group (97.6%) and the 45-59 years group(95.3%), followed by the ≥60 years group (81.2%), and the lowest rate in the 0-14 years group (27.8%). Mean negativeconversion time of SARS-CoV-2 RNA in mild group was longer than asymptomatic group (mild group vs asymptomaticgroup: (11.44±2.36) d vs (10.80±2.22) d, P<0.05. There were no statistically significant differences in gender, age, vacci-nation status, and number of days from the patient completing the vaccination to being infected between two groups (P>0.05). Survival analysis showed that the hazard ratio for nucleic acid test turns negative with the asymptomatic groupwas 1.281 (95% confidence interval [CI], 1.100 to 1.492, P=0.001). Subset analysis showed that there were no statistical-ly significant differences in gender, age, and vaccination status subsets (P>0.05). In the mild group, clinical symptomswere most frequent in cough (68.0%) and fever (29.1%). In Cox analyses, clinical symptoms were associated with virusnucleic acid turning negative. Conclusion SARS-CoV-2 Omicron BA.2 has universal susceptibility in different sexesand age groups, and the patients tend to be young, with respiratory symptoms and fever as the manifestations. Since theoutbreak of Omicron SARS-CoV-2 in Shanghai, the negative conversion time was similar to that of the original strain,and asymptomatic patients may have a shorter disease course than patients with mild symptoms.
      【Key words】 Coronavirus disease 2019; Novel coronavirus; OmicronBA.2 variant; Clinical characteristics; Sur-vival analysis