目的 通过免疫荧光抗原检测技术动态监测流感患儿流感病毒抗原，观察患儿抗原转阴时间和临床症状消失时间，以及两者之间的关系。方法 对2016年3~4月就诊于湖南省人民医院的1 063例疑似流感患儿运用甲乙型流感病毒抗原检测试剂盒（免疫荧光法）行流感病毒抗原检测，阳性者予以奥司他韦抗病毒治疗；并嘱咐患者起病后5 d内、5~7 d及7 d后3个时间段复查流感病毒抗原。结果 1 063例疑似流感病例中，流感病毒检出560例（52.68%）。对215例流感病毒阳性患儿进行随访，起病5 d内流感病毒抗原转阴率为9.8%（21例），5~7 d内累积转阴率为32.1%（69例），7~10 d累积转阴率为98.1%（211例）；起病3 d内临床症状改善率为2.8%（6例），3~5 d临床症状改善累积率为84.7%（182例），5 d后所有患儿临床症状均得到改善。结论 流感患儿经治疗临床症状改善时间早于抗原消失时间；起病7~10 d后流感病毒抗原近100%转阴，推测患儿在起病7~10 d、临床症状消失后返校是相对安全的。

Objective To investigate the antigen clearance time, time to symptom disappearance, and the association between them using immunofluorescence assay for dynamic monitoring of influenza virus antigen in children with influenza. Methods A total of 1 063 children suspected of influenza who visited the Hunan People's Hospital from March to April, 2016 were enrolled. The influenza A/B virus antigen detection kit (immunofluorescence assay) was used for influenza virus antigen detection. The children with positive results were given oseltamivir as the antiviral therapy and were asked to re-examine influenza virus antigen at 5, 5-7, and 7 days after onset. Results Of all children suspected of influenza, 560 (52.68%) had an influenza virus infection. A total of 215 children with influenza virus infection were followed up. The clearance rate of influenza virus antigen was 9.8% (21 cases) within 5 days after onset. The cumulative clearance rate of influenza virus antigen was 32.1% (69 cases) within 5-7 days, and 98.1% (211 cases) within 7-10 days after onset. Among these children, 6 children (2.8%) achieved the improvement in clinical symptoms within 3 days after onset. The cumulative rate of symptom improvement was 84.7% (182 cases) within 3-5 days after onset, and 100% achieved the improvement after 5 days of onset. Conclusions The time to improvement in symptoms after treatment is earlier than antigen clearance time. Almost all of the children achieve influenza virus antigen clearance 7-10 days after onset. Therefore, it is relatively safe for children to go back to school within 7-10 days after onset when symptoms disappear.