Abstract: Objective    To investigate the clinical value of respiratory syncytial virus （RSV） viral load in children with acute lower respiratory tract infection （ALRTI） and analyze its correlation with severe infection. Methods    The clinical data of 123 children with RSV nucleic acid or antigen positive ALRTI admitted to our hospital from July 2020 to December 2021 were collected，viral load detection and immune response characteristics were analyzed，and they were divided into mild infection group，moderate infection group and severe infection group. The clinical data of the three groups were compared. The correlation of viral load in ALRTI disease grading was analyzed. Results    A total of 123 cases were included，including 78 males （63.4%） and 45 females （36.6%），with a male to female ratio of 1.73∶1.00. There were 45 cases （36.6%） in the mild infection group，33 cases （26.8%） in the moderate infection group，and 45 cases （36.6%） in the severe infection group. Statistical analysis of data: RSV viral load was statistically significant between ALRTI severe infection group and moderate infection group，and between severe infection group and mild infection group （P<0.001）；CD4+ T cells increased in severe and moderate infection groups compared with mild infection group （P<0.05），and CD8+ T cells decreased compared with mild infection group （P<0.05）. Gender，age of onset and CD3+ T cells were not statistically significant in groups （P>0.05）. Conclusion    High viral load can easily cause severe RSV infection，and severe infection may occur in different ages and genders. Viral load detection and lymphocyte subsets analysis at the early stage of RSV infection can predict the severity of the disease to a certain extent，which is conducive to taking effective measures in time.

Key words: respiratory syncytial virus, child, lower respiratory tract infection, virus loading

摘要： 目的    探讨呼吸道合胞病毒（RSV）病毒载量在儿童急性下呼吸道感染（ALRTI）诊断治疗中的临床价值。方法    收集2020年7月至2021年12月广西壮族自治区妇幼保健院收治的123例RSV核酸或抗原阳性的儿童ALRTI临床资料，进行病毒载量检测并分析免疫反应特点，分为轻症状组、中症状组和重症状组，将3组临床资料进行比较，分析病毒载量在ALRTI病情分度的相关性。结果    共计纳入123例，其中男78例（63.4%），女45例（36.6%），男女比例1.73∶1；轻症状组45例（36.6%），中症状组33例（26.8%），重症状组45例（36.6%），不以特定发病月份收集。在ALRTI重症状组与中症状组、轻症状组RSV病毒载量组间比较，差异有统计学意义（P<0.001）；中症状组CD4+T较轻症状组高（P<0.05），CD8+T则较轻症状组低（P<0.05），性别、发病年龄段、CD3+T、白细胞在分组中差异无统计学意义（P>0.05）。结论    高病毒载量易引起重症RSV感染，不同年龄及性别上，均可出现重症感染可能，RSV感染早期进行病毒载量检测及淋巴细胞亚群的分析可在一定程度上预测疾病严重程度，有利于及时采取有效措施。

关键词: 呼吸道合胞病毒, 儿童, 下呼吸道感染, 病毒载量