Beijing Key Laboratory of Pediatric Respiratory Infection diseases, Key Laboratory of Major Diseases in Children, Ministry of Education, National Clinical Research Center for Respiratory Diseases, Research Unit of Critical Infection in Children, Chinese Acadesmy of Medical Sciences, 2019RU016, Laboratory of Infection and Virology, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China; Department of Microbiology and Parasitology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China.
Department of Microbiology and Parasitology, School of Basic Medical Sciences, Capital Medical University, Beijing 100069, China.
Infect Genet Evol. 2020 Nov;85:104476. doi: 10.1016/j.meegid.2020.104476. Epub 2020 Jul 29.
Japanese encephalitis (JE), caused by infection with Japanese encephalitis virus (JEV), is the most important viral encephalitis in Asia. JE incidence has significantly decreased by immunization with live-attenuated vaccine SA14-14-2. However, the duration of immune response overtime after vaccination is inconclusive and may be associated with the risk of JE occurrence in adults. A cross-sectional study was conducted in 961 JE-vaccinated local residents aged 19-20 years in Beijing, China. 620 (65%) and 513 (53%) individuals were anti-JEV IgG antibody and neutralizing antibody (nAb) positive, respectively. The geometric mean titer (GMT) of nAb was 1:11, suggesting a seroprotection among the study population. As for IFN-γ production, peripheral blood mononuclear cell (PBMC) samples isolated from 60 subjects showed negative response following the stimulation with concentrated JEV particles. Overall, longer persistence of nAb response among vaccinees is observed than that of cellular immune response after 17-18 years of vaccination. Taken together, our results not only provide the data for evaluating herd immunity against JEV among vaccinated adults in Beijing but also offer useful information for JE prevention and control in endemic areas.
日本脑炎（JE）是由日本脑炎病毒（JEV）感染引起的，是亚洲最重要的病毒性脑炎。通过接种减毒活疫苗 SA14-14-2，JE 的发病率显著下降。然而，接种后免疫反应的持续时间尚不确定，并且可能与成年人发生 JE 的风险有关。在中国北京，对 961 名接种 JE 疫苗的 19-20 岁当地居民进行了一项横断面研究。分别有 620 名（65%）和 513 名（53%）个体的抗 JEV IgG 抗体和中和抗体（nAb）呈阳性。nAb 的几何平均滴度（GMT）为 1:11，表明研究人群中具有血清保护力。至于 IFN-γ 的产生，从 60 名受试者中分离的外周血单核细胞（PBMC）样本在受到浓缩 JEV 颗粒刺激后显示出阴性反应。总体而言，接种疫苗后 17-18 年后，nAb 反应的持续时间比细胞免疫反应更长。总之，我们的研究结果不仅为评估北京接种成年人对 JEV 的群体免疫力提供了数据，而且为流行地区的 JE 预防和控制提供了有用信息。
