上海市儿童和青少年甲型肝炎抗体水平与影响因素

Seroprevalence of total hepatitis A virus antibody in children and adolescents in Shanghai and its risk factors

目的了解上海市O～18岁儿童和青少年甲型肝炎疫苗的免疫状况和甲型肝炎抗体分布水平，分析儿童和青少年发生HAV自然感染的影响因素。方法用分层整群随机抽样的方法，以上海市0～18岁人群为研究对象，通过问卷调查收集研究对象的人口学和饮食行为等相关信息，从预防接种记录本摘录研究对象的免疫接种史。用ELISA方法定性和定量检测调查对象血清样本中的甲型肝炎抗体，分析影响未接种疫苗研究对象HAV自然感染的因素。结果共纳入调查对象2431名，HAVIgM抗体均为阴性，甲型肝炎总抗体阳性为1483名，阳性率为61％。调查对象随年龄增长，甲型肝炎总抗体阳性率有下降趋势，有甲型肝炎疫苗接种史的儿童和青少年的甲型肝炎抗体阳性率显著高于无接种记录的对象，经常食用凉拌菜、集体单位非分餐进食和内镜检查是发生HAV感染的危险因素。结论既往上海市的甲型肝炎疫苗接种策略显著提高了儿童和青少年部分年龄组人群的甲型肝炎抗体水平，未接种甲型肝炎疫苗的儿童和青少年仍存在自然感染HAV的可能，故加强甲型肝炎疫苗接种、开展甲型肝炎防治健康教育对上海市儿童和青少年的甲型肝炎防控非常重要。

Objective To investigate the immunity and seroprevalenee of hepatitis A and to identify the risk factors of hepatitis A infection in 0--18 year-old children and adolescents in Shanghai. Methods Subjects were enrolled by stratifying and clustering random sampling method. Questionnaire interview was applied to investigate the socio-demographic and behavioral factors related to hepatitis A virus （HAV）, and information on HAV immunization was abstracted from the immunization registration book of each subject. The enzyme-linked immunosorbent assay （ELISA） was used to qualitatively detect HAV IgM and quantitatively measure total HAV antibody in all subjects. Risk factors associated with HAV among the subjects without HAV vaccination were analyzed. Results A total of 2431 subjects were enrolled in the present study with negative HAV IgM antibody and total HAV antibody in 1483 subjects were sero-positive with positivity rate of 61~. Total HAV antibody positivity rates were declined with age increasing and were significantly higher in subjects with HAV vaccination than those without HAV vaccination records. Salad food, eating together without food separation in school and endoscopy inspection were risk factors for HAV infection. Conclusions HAV vaccination strategies remarkably improve the total HAV antibody seropositive rate in children and adolescents in Shanghai. The risk of HAV infection exists if HAV vaccination is not administrated comprehensively. Therefore, strengthening HAV vaccination and health education are important for children and adolescents to prevent and control of hepatitis A in Shanghai.