目的对某小学水痘暴发疫情进行流行病学调查,并对水痘疫苗应急接种效果进行血清学评价,为学校水痘暴发控制提供参考。方法收集病例病史资料及病例所在年级学生疫苗接种史和既往水痘病史,对应急接种对象分别于接种前、接种后2周、4周采集手指末梢血,用定量酶联免疫吸附试验(Enzyme-linked Immunosorbent Assay,ELISA)检测水痘IgG。结果本次暴发共发生水痘13例,病例所在的年级罹患率为9.29%,有接种史的罹患率为7.58%,无接种史的罹患率为33.33%,无接种史的罹患率显著高于有接种史者,疫苗保护率(Vaccine Efficacy,VE)为77.26%。应急接种前接种对象抗体阳性率为72.73%,免后2周、4周抗体阳性率均为100%。免后抗体浓度明显高于免前抗体浓度,且免后2周抗体浓度明显高于免后4周抗体浓度。结论水痘疫苗能有效预防水痘,建议对接种1剂水痘疫苗的儿童间隔满3年后再推荐加强接种1剂。水痘疫苗的应急接种能迅速提高易感者体内的抗体水平,有助于水痘暴发的控制。 Objective To investigate the epidemiology of chickenpox outbreak in a primary school and to evaluate the effect of vaccination against chickenpox vaccine in order to provide reference for the control of school chicken pox outbreak. Methods The data of medical history and past history of vaccination of varicella patients were collected. The emergency vaccination subjects were collected before and 2 weeks and 4 weeks after inoculation respectively. The peripheral blood of finger was collected and quantified by enzyme-linked immunosorbent assay Immunosorbent Assay, ELISA) for the detection of varicella IgG. Results Thirteen outbreaks of chickenpox occurred in this outbreak. The attack rate was 9.29% in the grade of the case. The attack rate was 7.58% in the history of vaccination and 33.33% in the history without vaccination. The attack rate in non-vaccination history was significantly higher than that in the non- Vaccination history, vaccine protection rate (Vaccine Efficacy, VE) was 77.26%. The positive rate of antibody inoculated before emergency inoculation was 72.73%, and the positive rate of antibody in two weeks and 4 weeks after immunization was 100%. The post-immunization antibody concentration was significantly higher than that of pre-free antibody, and the antibody concentration was significantly higher at 2 weeks after immunization than at 4 weeks after immunization. Conclusions The chickenpox vaccine is effective in preventing chickenpox. It is recommended that one dose of the vaccine be recommended for children vaccinated with one dose of varicella vaccine after 3 years of interval. Vaccination of chickenpox vaccines can rapidly increase the level of antibodies in susceptible individuals and contribute to the control of varicella outbreaks.