目的 探讨儿童新冠病毒Omicron株感染临床特征及其相关影响因素。方法 收集94例Omicron株感染患儿的临床表现、实验室检查、肺部CT影像、核酸检测、临床分型、疫苗接种和诊治疗效等资料进行分析总结。结果 94例中男51例（54.3%）、女43例,年龄9天~14岁（平均4.5±3.3岁）,接种过疫苗33例。所有患儿均有与Omicron感染病例密切接触史。无症状与轻症占76.6%。肺炎组患儿外周血淋巴细胞绝对计数均值（2.66×10⁹/L）显著低于无症状/轻症组（4.18×10⁹/L）,P=0.024。疫苗接种与未接种患儿比较,无症状与轻症占比显著增高（90.9%对68.9%,P=0.013）,发热人数明显减少（42.4%对70.5%,P=0.008）,平均住院天数明显缩短（P=0.026）;ORF1ab与N基因C_t值均高于未接种者（P均<0.05）。以中药汤剂经典处方加减行个体化辨证施治,联合经验性抗生素（头孢菌素或大环内酯类）治疗后患儿均痊愈,平均住院（8.5±3.8） 天。1例重症患儿经积极抗继发感染、抗凝和短程糖皮质激素等综合治疗,病情得以及时控制。结论 儿童对于Omicron株普遍易感,疫苗接种有助于提高特异性免疫力,故加强隔离防护和疫苗接种,均为预防儿童Omicron感染的有效措施。

Objective To explore the clinical characteristics and related factors of SARS-CoV-2 Omicron variant infection in children. Methods The clinical manifestations, laboratory tests, pulmonary CT imaging, nucleic acid detection, clinical typing, vaccination and therapeutic efficacy of 94 children with Omicron infection were analyzed and summarized. Results A total of 94 children were enrolled, including 51 boys (54.3%) and 43 girls, aged from 9 days to 14 years (mean, 4.5±3.3 years), 33 of whom had been vaccinated. All children had a history of close contact with Omicron infected patients. Asymptomatic and mild cases accounted for 76.6%. The mean value of peripheral blood absolute lymphocyte count in pneumonia group was 2.66×10⁹/L, which was significantly lower than that (4.18×10⁹/L) in asymptomatic/mild group (P=0.024). Compared with non-vaccinated group, the proportion of asymptomatic and mild cases was significantly higher (90.9% vs 68.9%, P=0.013), the number of children with fever was lower (42.4% vs 70.5%, P=0.008), and the average length of hospital stay was significantly shorter (P=0.026) in vaccinated group. The C_t values of ORF1ab and N gene in vaccinated group were significantly higher than those in non-vaccinated group (P<0.05). Individualized syndrome differentiation and treatment was carried out by adding or subtracting classic prescription of traditional Chinese medicine decoction and empiric antibiotics (cephalosporins or macrolides) were administered in combination. All patients recovered, and the average hospital stay was (8.5±3.8) days. One severe case was controlled in time by comprehensive therapy including active anti-secondary infection, anticoagulant drugs and short course glucocorticoids. Conclusions Children are generally susceptible to the Omicron strains, and vaccination helps to improve specific immunity. Therefore, strengthening isolation and vaccination are effective measures to prevent Omicron infection in children.