陕西省铜川市健康人群流行性乙型脑炎中和抗体水平监测结果分析

Surveillance of neutralization antibody to Japanese encephalitis virus in healthy population in Tongchuan city,Shaanxi province

目的了解陕西省铜川市健康人群流行性乙型脑炎（乙脑）抗体水平，为有效防控乙脑提供参考依据。方法采用整群随机抽样的方法，选择铜川市宜君县≤2岁、3～5岁、6～10岁、11～15岁、16～45岁、46～60岁和〉60岁组共216人，用微量中和试验检测乙脑病毒中和抗体。结果铜川市健康人群乙脑中和抗体阳性率为24．07％，抗体几何平均滴度（GMT）为1：3．04；≤2岁组人群抗体阳性率及GMT均最高，为63．33％和1：11．06，其他年龄组的抗体阳性率为6．45％～31．03％，抗体GMT为1：1．78—1：3．95。各年龄组抗体阳性率及GMT差异有统计学意义。结论铜川市缝康人群乙脑抗体阳性率及GMT均较低，具有引发乙脑流行的风险，应加强乙脑疫苗免疫接种工作，提高人群免疫覆盖率。

Objective To understand Japanese encephalitis virus （JEV） antibody level in the healthy population in Tongchuan, and provide scientific evidence for the prevention and control of Japanese encephalitis. Methods Totally 216 healthy people in 7 age groups （ ≤2, 3 -5, 6 - 10, 11 - 15, 16 -45,46 -60 and 〉60 years old） were sampled by cluster random sampling in Yijun county of Tongchuan, and blood samples were taken from them to detect neutralization antibody （NA） to JEV by micro neutralization test. Results The positive rate of JEV NA （GMT） was 24.07% （1：3.04） in the healthy population in Tongchuan. The positive rate （GMT） in age group ≤2 years old was highest （63.33%, 1：11.06）, the positive rates and GMT in other age groups ranged from 6. 45% to 31.03% and from 1：1.78 to 1：3.95 respectively. The differences on antibody levels between different age groups were statistical significant. Conclusion The JEV antibody positive rate and GMT were relatively low in the healthy population in Tongchuan, which might facilitate the epidemic of Japanese encephalitis. It is necessary to strengthen the Japanese encephalitis vaccination to increase the vaccination coverage.