儿童新型冠状病毒疫苗突破性感染的临床特点

Clinical characteristics of severe acute respiratory syndrome coronavirus 2 vaccine breakthrough infections in children

目的:分析儿童新型冠状病毒疫苗突破性感染的临床特点,为指导儿童接种新型冠状病毒疫苗提供参考依据。方法:纳入2021年12月27日至2022年2月7日西安市人民医院(西安市第四医院)收治的97例3~14岁新型冠状病毒感染(COVID-19)患儿,根据是否接种新型冠状病毒疫苗,分成未接种组、部分接种组和完全接种组,比较3组的临床资料。统计学方法采用χ^(2)检验、两独立样本t检验和Kruskal-Wallis H检验。结果:97例COVID-19患儿中,男49例,女48例;轻型87例(89.7%),普通型10例(10.3%),无重型及危重型。学龄前儿童(3~6岁)未接种、部分接种和完全接种的比例分别为56.5%(13/23)、30.8%(12/39)和17.1%(6/35),进度缓于学龄儿童(7~14岁)的43.5%(10/23)、69.2%(27/39)和82.9%(29/35),差异有统计学意义(χ^(2)=9.94,P=0.007)。完全接种疫苗患儿发热的比例为17.1%(6/35),低于未接种疫苗患儿的43.5%(10/23),差异有统计学意义(χ^(2)=4.82,P=0.028)。未接种、部分接种和完全接种疫苗组入院时核酸检测结果显示,新型冠状病毒开放阅读框(ORF)1 ab基因循环阈值(Ct值)分别为33.77(26.87,36.58)、35.23(33.45,38.57)和37.12(34.91,39.39),差异有统计学意义(H=7.76,P=0.021);核衣壳蛋白(N)基因Ct值分别为32.26(25.85,36.18)、35.12(33.18,37.96)和37.26(34.27,39.24),差异有统计学意义(H=7.84,P=0.020)。完全接种组核酸检测ORF1 ab基因及N基因Ct值均高于未接种组,差异均有统计学意义(Z=-2.69,P=0.007;Z=-2.39,P=0.017)。完全接种组的病毒转阴时间为(9.9±4.1)d,短于未接种组的(12.8±3.7)d,差异有统计学意义(t=2.72,P=0.009)。结论:新型冠状病毒疫苗突破性感染患儿以轻症为主,接种疫苗可缩短病毒转阴时间。与未接种疫苗患儿相比,完全接种疫苗患儿的临床症状较轻,病毒载量较低。

Objective To analyze the clinical characteristics of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)vaccine breakthrough infections in children,and to provide reference basis for the SARS-CoV-2 vaccination in children.Methods A total of 97 children aged 3 to 14 years and diagnosed with coronavirus disease 2019(COVID-19)admitted to Xi′an People′s Hospital(Xi′an Fourth Hospital)from December 27,2021 to February 7,2022 were included.According to the COVID-19 vaccination status,the enrolled children were divided into unvaccinated group,partially vaccinated group and fully vaccinated group,and the clinical data of the children in the three groups were collected and compared.Chi-square test,two independent sample t-test and Kruskal-Wallis H test were used for statistical analysis.Results Totally 97 children including 49 males and 48 females were enrolled,with 87(89.7%)children of mild type,10(10.3%)children of common type,and no severe or critical case.The proportions of unvaccinated,partially vaccinated and fully vaccinated preschool-aged children(3 to 6 years old)were 56.5%(13/23),30.8%(12/39)and 17.1%(6/35),respectively,while those of school-aged children(7 to 14 years old)were 43.5%(10/23),69.2%(27/39)and 82.9%(29/35),respectively.The vaccination proportion in preschool-aged children was significantly lower than that in school-age children(χ^(2)=9.94,P=0.007).The proportion of the children with fever in fully vaccinated group was 17.1%(6/35),which was lower than that in unvaccinated group(43.5%,10/23),and the difference was statistically significant(χ^(2)=4.82,P=0.028).The cycle threshold(Ct)values of the open reading frame(ORF)1ab gene in the unvaccinated,partially vaccinated and fully vaccinated groups were 33.77(26.87,36.58),35.23(33.45,38.57)and 37.12(34.91,39.39),respectively,and there was a statistically significant difference among the groups(H=7.76,P=0.021).The Ct values of the nucleocapsid protein(N)gene in the three groups were 32.26(25.85,36.18),35.12(33.18,37.96)and 37.26(34.27,39.24),respectively,and the difference among the groups was statistically significant(H=7.84,P=0.020).The Ct values of ORF1ab gene and N gene in fully vaccinated group were higher than those in unvaccinated group,and the differences were statistically significant(Z=-2.69,P=0.007 and Z=-2.39,P=0.017,respectively).The duration of viral shedding in fully vaccinated children was(9.9±4.1)d,which was shorter than that in unvaccinated children((12.8±3.7)d),and the difference was statistically significant(t=2.72,P=0.009).Conclusions The majority of children with breakthrough infections with SARS-CoV-2 are mild.Vaccination may effectively shorten the duration of viral shedding.And fully vaccination is associated with mild clinical symptoms and lower serum viral load compared to unvaccinated children.