流行性乙型脑炎减毒活疫苗的血清学观察

我国目前生产供应的乙型脑炎疫苗有两种:一是地鼠肾细胞灭活疫苗,一是地鼠肾细胞减毒活疫苗.由于后者针次少、反应率及反应强度较小且安全,近年来得到推广使用.为了解该疫苗在人群中的血清学免疫效果及反应情况,我们对所在门诊74例1～2岁幼儿进行了观察.现将结果报告如下.     

流行性乙型脑炎减毒活疫苗免疫效果观察

目的评价流行性乙型脑炎减毒活疫苗的免疫效果。方法在北京市东城和昌平2个区随机选择满1周岁未接种过乙型脑炎疫苗的儿童99名，采集乙脑疫苗免疫前、免疫后1-2个月和2周岁加强免疫后1～2个月的外周静脉血各1份，分离血清检测血清乙型脑炎中和抗体。结果乙型脑炎减毒活疫苗的初次免疫成功率86．87％，95％CI（80．22％～93．52％），GMT1：17．86；加强免疫成功率97．33％，95％CI（93．68％～99．98％），GMT1：97．82。结论乙型脑炎减毒活疫苗具有较好的免疫原性，且该疫苗为单人份包装，更利于安全接种，适合基层推广。     

麻疹减毒活疫苗效力的Meta分析

目的了解麻疹减毒活疫苗(MV)效力。方法对国内1998年3月~2007年3月公开发表的符合入选标准的有关MV效力的研究文献,根据各研究结果的一致性,利用随机效应模型或固定效应模型进行Meta分析。结果有7篇文献符合入选标准,均为MV效力的病例对照研究。结果发现MV效力为82.9%[95%可信区间(CI)66.5%~91.7%],低年龄儿童MV效力为85.2%(95%CI:65.2%~93.7%),高年龄儿童MV效力为65.7%(95%CI:42.3%~79.6%)。结论MV效力低于理论的95%,提示为预防和控制麻疹爆发、流行,应提高和维持高水平的MV初免和复种接种率。     

流行性乙型脑炎减毒活疫苗血清学效果观察

为进一步考核用ＳＡ１４－１４－２株生产的流行性乙型脑炎（乙脑）减毒活疫苗接种儿童后的血清学效果，在湖北省乙脑流行区，对某山区小学从未接种过乙脑疫苗的９７名７～１３岁健康小学生接种该疫苗。免疫前和免疫后１个月采血检测乙脑中和抗体，结果：免前中和抗体阳性者８６人（８８．６６％），中和指数ＧＭＴ为１：６９５．３２，免疫１针后１个月，抗体阳性率达到１００％，中和指数ＧＭＴ为１：２７７８．２７；免疫前抗体阴性的１１名儿童，免疫后１个月全部阳转；免疫前中和指数≥１１０００者５４人（占５５．６７％），免疫后１个月增至８１人（８３．５１％）；６０．８２％的儿童免疫后１个月中和抗体滴度较免疫前增长≥２倍。这证明该疫苗免疫效果良好     

流行性乙型脑炎减毒活疫苗免疫学效果观察

1998年5月,我们在江苏省新沂市选择1～1．5岁健康儿童进行流行性乙型脑炎（乙脑）减毒活疫苗免疫学效果观察．免疫前和免疫后1个月各采血检测乙脑反向被动血凝（RPHI）抗体．检测到合格双份血清87人,抗体测定免疫前阴性44人．其免疫后抗体阳转率为93．18％,免疫前阳性43人,其免疫后抗体≥4倍增长率为34．88％,表明乙脑减毒活疫苗的免疫成功率是较高的．     

流行性乙型脑炎减毒活疫苗免疫接种安全性观察

免疫接种流行性乙型脑炎(乙脑)灭活疫苗对降低人群的乙脑发病率,已收到了显著的效果.但同时存在"接种针次多、剂量大、接种反应较多",甚至"危及生命"等[1,2]问题,为此我们于1999年1～2月在江山市对3259名健康儿童进行了乙脑减毒活疫苗的免疫接种安全性观察,现报告如下.     

流行性乙型脑炎减毒活疫苗与灭活疫苗免疫效果观察

我国是流行性乙型脑炎(乙脑)流行区,预防和控制乙脑发病的主要手段是接种乙脑疫苗。20世纪70年代开始使用乙脑灭活疫苗,初免接种两针,间隔时间7~10 d。80年代乙脑减毒活疫苗研制成功,初免仅需接种1针。减毒活疫苗从2004年5月在山东省威海地区开始使用。为比较两种疫苗免疫效果,     

四川省地震灾区甲型肝炎疫苗和流行性乙型脑炎减毒活疫苗群体性预防接种分析

目的 评价四川省地震灾区甲型肝炎(甲肝)疫苗(Hepatitis A Vaccine,HepA)、流行性乙型脑炎(乙脑)减毒活疫苗(Japanese Encephalitis Vaccine,LivedEV-1)群体性预防接种.方法 对报告和现场调查的HepA、JEV-1接种数据进行分析.结果 四川省地震灾区6个市(州)21个县(区、市),截止到2008年6月10日,共报告接种HepA399 075人,接种JEV-1 137 543人,估算接种率分别为91.96％、88.85％.现场快速调查HepA应种1825人,实种1783人,接种率97.70％;JEV-1应种912人,实种869人,接种率95.29％.结论 四川省地震灾区HepA、JEV-1群体性预防接种达到了预期结果.     

流行性乙型脑炎减毒活疫苗的发展和应用

<正>我国的流行性乙型脑炎(乙脑)减毒活疫苗自1989年获新药证书以来,生产量不断增多,至今疫苗产量已达3亿人份,实际应用人数已超过2亿,大量人群应用后表明,疫苗十分安全, 未发现与疫苗相关的脑炎病例,经国内外不同乙脑流行区使用证明,预防效果显著。现将该疫苗的发展和应用概况介绍如下。     

流行性乙型脑炎减毒活疫苗效果的病例对照研究

为了解流行性乙型脑炎 (乙脑 )减毒活疫苗在乙脑流行时的保护效果 ,对 2 0 0 0年发生乙脑流行的重庆市万州区 1～ 6岁临床诊断病例 4 7例 ,按照 1∶2配对进行乙脑减毒活疫苗免疫接种史调查。结果显示 :乙脑病例和对照中 ,有免疫接种史的分别占 2 13% (1/47)和 35 11% (33/94 )。乙脑减毒活疫苗对 1～ 6岁儿童的保护率为95 98% ,95 %可信限为 72 0 3%～ 99 4 2 % ,即最低的保护率为 72 0 3%。接种乙脑减毒活疫苗可提高人群免疫力 ,在乙脑流行时有较好的保护效果。     

流行性乙型脑炎灭活疫苗与减毒活疫苗相结合的免疫策略研究

目的　为合理利用流行性乙型脑炎 (乙脑 )灭活疫苗和减毒活疫苗各自的优点 ,降低预防接种反应的发生率 ,提高免疫学效果 ,开展了乙脑灭活疫苗与减毒活疫苗相结合的免疫策略研究。方法　观察比较两种疫苗单一使用与联合使用的免疫学效果及安全性。结果　联合使用组在疫苗接种后 2 4h的全身中强以上发热反应发生率为 0 .73 % ,局部红晕反应为 1 .46 % ,而单一使用灭活疫苗组的发热反应发生率为 2 .8%。不同观察组疫苗接种后中和抗体几何平均滴度由免疫前的 1∶1 .0 5～1∶3 .35上升至 1∶47.34～ 1∶1 0 1 .30 ,联合使用组的中和抗体阳转率为 97.67% ,明显高于单一使用灭活疫苗组 86 .2 7%的阳转率 (χ2 =3 .89,P <0 .0 5) ,但与单一使用减毒活疫苗组 93 .75 %的阳转率差异无显著性 (χ2 =0 .74,P >0 .0 5)。结论　研究表明对婴幼儿使用乙脑灭活疫苗基础免疫、减毒活疫苗加强免疫有很好的免疫学效果及安全性 ,也是切实可行和比较理想的免疫策略     

2009-2018年宁夏回族自治区乙脑减毒活疫苗疑似预防接种异常反应分析

目的 分析宁夏回族自治区2009-2018年乙脑减毒活疫苗(Japanese Encephalitis Vaccine,Live,JEV-L)接种后疑似预防接种异常反应(adverse events following immunization,AEFI)的发生特征,评价JEV-L预防接种安全性。方法 采用描述流行病学方法对2009-2018年宁夏回族自治区AEFI信息管理系统中报告的接种JEV-L后AEFI个案进行分析。结果 2009-2018年宁夏回族自治区共报告接种JEV-L后AEFI 1510例,报告发生率73.4 /10万;50%发生在5-8月;男女性别比1.1〖DK〗∶1;91.52%为8-23月儿童;一般反应1484例,报告发生率72.1/10万,异常反应20例,报告发生率1.0/10万;一般反应以发热为主,报告发生率67.3/10万,异常反应以过敏性皮疹为主,报告发生率0.8/10万;98.5%发生在接种后1d内;99.7%治愈,0.3%好转。结论 宁夏回族自治区AEFI监测敏感性高,JEV-L预防接种安全性较好,需重点关注接种后24小时内发热和过敏性皮疹的发生。     

Immunogenicity and safety of the third booster dose of the inactivated Japanese encephalitis vaccine in Korean children: A prospective multicenter study

The immunization schedule for the inactivated Japanese encephalitis (JE) vaccine in Korea is a two-dose primary series at 12–24 months of age and three booster doses at 12 months after primary schedule and at 6 and 12 years of age. The aim of this study was to investigate immunogenicity and safety of the third booster dose of the inactivated JE vaccine, as well as the long-term immunogenicity of the second booster dose in Korean children. Healthy children aged 11–13 years, primed and given four doses of inactivated JE vaccines were included. All subjects received the third booster dose of the JE vaccine. Neutralizing antibody (NTAb) titers were assessed before and 4–6 weeks after vaccination using plaque reduction neutralization test (PRNT), and were considered to be protective at ≥ 1:10. Local and systemic adverse events were monitored for 4 weeks after vaccination. Before and after booster vaccination, all seroprotection rates were 100%. Geometric mean titer (GMT) showed a 6.05–fold increase, from 139.11 (95% CI: 110.76, 174.71) to 841.53 (95% CI, 714.25, 991.50). The local tolerability and systemic safety profiles were favorable, with no serious adverse events. In conclusion, the third booster dose of the inactivated JE vaccine was demonstrated to be safe and immunogenic in Korean children when administered according to the current immunization schedule.     

水痘减毒活疫苗现场流行病学保护效力的Meta分析

目的 评价水痘减毒活疫苗现场流行病学保护效力,为优化水痘减毒活疫苗免疫程序提供依据.方法 电子检索《中国期刊全文数据库》和《美国国家医学图书馆数据库》,采用Meta分析对2000年以来发表的水痘减毒活疫苗保护效力病例对照研究的文献进行汇总、归纳和统计分析.使用RevMan5.1软件进行统计分析.结果 共纳入24篇文献.水痘减毒活疫苗总保护效力为69％ (95 ％CI:60％～75％),对幼儿(＜7岁)保护效力为86％ (95％CI:75％～92％),对小学生(≥7岁)的保护效力为67％(95％CI:50％～79％).结论 水痘减毒活疫苗具有一定的保护效力,但随着时间的推移保护效果降低.     

流感减毒活疫苗预防儿童季节性流感保护效果的Meta分析

目的评价流感减毒活疫苗(LAIV)预防2~17岁儿童季节性流感的保护效果。方法通过Web of Science、PubMed和ScienceDirect数据库,检索2003年1月至2018年11月期间发表的、研究设计为病例对照的、关于研究LAIV预防儿童季节性流感保护效果的相关文献,采用Stata 13.1软件对纳入文献进行Meta分析。结果共纳入文献14篇,均为检测阴性设计(Test-negative design,TND)研究。结果显示LAIV预防儿童季节性流感的保护效果为49%(95%CI:40%~57%)。亚组分析发现:LAIV预防A(H1N1)pdm09型、A(H3N2)型和B型流感的保护效果分别为35%(95%CI:5%~56%)、35%(95%CI:21%~46%)和71%(95%CI:55%~82%);三价LAIV和四价LAIV在儿童中的保护效果分别为56%(95%CI:48%~63%)和44%(95%CI:27%~57%);LAIV在欧洲地区和北美洲地区的保护效果分别为65%(95%CI:47%~77%)和46%(95%CI:36%~55%)。结论LAIV对2~17岁儿童季节性流感具有一定的预防作用。     

2011—2018年郴州市乙型脑炎减毒活疫苗预防接种不良反应监测分析

目的 分析2011—2018年郴州市乙型脑炎减毒活疫苗(Japanese encephalitis attenuated live vaccine, JEV-L)预防接种不良反应的发生特征和预防接种安全性。 方法 通过国家疑似预防接种异常反应(adverse events following immunization, AEFI)信息管理系统收集郴州市2011—2018年报告的JEV-L预防接种不良反应个案数据,采用描述流行病学方法进行分析。 结果 2011—2018年郴州市共报告JEV-L预防接种不良反应421例,年平均报告发生率为43.55/10万剂。其中一般反应404例(95.96%,41.79/10万剂);异常反应17例(4.04%,1.76/10万剂);男女性别比为1.38∶1;<3岁的儿童占92.16%;个案报告主要集中在第二季度,占42.99%;第1剂次不良反应发生率高于第2剂次,差异有统计学意义(χ²=37.22,P<0.01);98.81%的不良反应发生在接种后24 h之内。 结论 JEV-L具有较好的安全性,仍需加强JEV-L不良反应监测工作。     

Immunogenicity of one dose of Vero cell culture-derived Japanese encephalitis (JE) vaccine in adults previously vaccinated with mouse brain-derived JE vaccine

Background

There are no data on the use of inactivated Vero cell culture-derived Japanese encephalitis (JE) vaccine (JE-VC) as a booster among individuals who previously received inactivated mouse brain-derived JE vaccine (JE-MB).

Methods

Military personnel who received ≥3 doses of JE-MB or were JE vaccine-naïve were vaccinated with 2 doses of JE-VC on days 0 and 28. Serum neutralizing antibodies were measured pre-vaccination and 28 days after each dose. Non-inferiority was evaluated for seroprotection rate and geometric mean titer (GMT) between previously vaccinated participants post-dose 1 and vaccine-naïve participants post-dose 2.

Results

Fifty-three previously vaccinated and 70 JE vaccine-naïve participants were enrolled. Previously vaccinated participants had significantly higher GMTs pre-vaccination, post-dose 1, and post-dose 2. Seroprotection rates among previously vaccinated participants post-dose 1 (44/44, 100%) were noninferior to those achieved in previously naïve participants post-dose 2 (53/57, 93%). The GMT was significantly higher in previously vaccinated participants post-dose 1 (GMT 315; 95% CI 191–520) compared to previously naïve participants post-dose 2 (GMT 79; 95% CI 54–114).

Conclusions

Among military personnel previously vaccinated with ≥3 doses of JE-MB, a single dose of JE-VC adequately boosts neutralizing antibody levels and provides at least short-term protection. Additional studies are needed to confirm these findings in other populations and determine the duration of protection following a single dose of JE-VC in prior recipients of JE-MB.     

Modelling the long-term persistence of neutralizing antibody in adults after one dose of live attenuated Japanese encephalitis chimeric virus vaccine

In a study conducted in a non-endemic area, a live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) was found to provide 97% seroprotection at 6 months in JE-naive adults after 1 dose, and 87% of those protected at 6 months were still protected at 5 years. Because long-term seroprotection data are essential for decision-making on the need and timing of boosters, we applied statistical models to this dataset to predict individuals' neutralizing antibody titres and seroprotection up to 25 years post-vaccination. Three types of statistical model (linear, piecewise linear and exponential-type) with fixed and random effects were constructed to model antibody decline from the observed peak in antibody levels measured 28 days after vaccination. Individual seroprotection was based on the accepted threshold of 1:10 dilution units (antibody titre ≥10). The piecewise linear mixed model provided best fit amongst all tested models and identified 2 periods of antibody decline: an initial period of rapid decline followed by a period of much slower decline (50 times) starting on average 3.2 months (5th to 95th percentile range: 1.4-7.3) after vaccination. Predicted median antibody titres at 10 years were 38 (<10-174) and the corresponding seroprotection rate was 85.5% (72.7-94.9). The estimated median duration of seroprotection was 21.4 years (5th to 95th percentile range: 7.3-34.0). This analysis suggests that one dose of JE-CV confers to most adults a high level of protection against Japanese encephalitis for at least 10 years.     

甲型肝炎减毒活疫苗加强免疫效果的初步研究

目的　观察甲型肝炎 (甲肝 )减毒活疫菌 (10 7.0 TCID50 )加强免疫效果 ,并同活疫苗一针法结果进行比较。方法　在河北省正定县选择 42名经事先检测甲肝抗体阴性的易感儿童 ,分别于0、2和 6个月各接种一剂甲肝减毒活疫苗 ,并于接种后 1、2、6、7、9和 12个月采集血清标本 ,观察免后抗体动态变化。结果　第 1剂接种后 1个月抗体阳转率达 81.4% ,第 2剂免后抗体阳转率达 10 0 % ,抗体水平于第 3剂免后 1个月达高峰 ,为 2 739mIU/ml,以后呈下降趋势 ,免后 12个月抗体阳转率仍为 10 0 % ,抗体水平下降至 979mIU/ml。结论　甲型肝炎减毒活疫苗加强免疫能诱导良好的免疫回忆反应 ,其免疫学效果同史克灭活疫苗相当 ,而明显高于活疫苗一针法。活疫苗加强免疫中 ,初免是基础。活疫苗加强免疫会提高疫苗保护效果 ,并延长疫苗的免疫持久性     

Long-term follow-up of Japanese encephalitis chimeric virus vaccine: Immune responses in children

BackgroundA single dose of live attenuated Japanese encephalitis chimeric virus vaccine (JE-CV) was shown to be immunogenic and well tolerated when given either as a booster to formalin-inactivated Japanese encephalitis (JE)-vaccine (mouse brain-derived vaccine [MBDV])-primed 2–5-year-olds, or as a primary vaccination to JE-vaccine-naïve 12–24-month-old toddlers in Thailand. A 5-year follow-up assessment of immune response persistence over time was conducted.MethodsFour additional visits (at 2, 3, 4, and 5 years) for immunologic assessments were added to the original 12-month open-label crossover study, in which 100 healthy children aged 2–5 years with a history of two-dose primary vaccination with MBDV (according to the Thai Expanded Program for Immunization schedule), and 200 healthy JE-vaccine-naïve 12–24-month-old toddlers, were randomized 1:1 to receive JE-CV, containing ⩾4 log₁₀ plaque forming units, 1 month before or after hepatitis A control vaccine.ResultsIn MBDV-primed 2–5-year-olds (n = 78), the immune response to the JE-CV vaccine persisted up to at least 5 years after vaccination with a single dose of JE-CV, with all (n = 78) children seroprotected at the year 5 visit (geometric mean titers [GMT]: 252 1/dil). There was no decrease of seroprotection rate over time (100% at 6 months post-vaccination and 96.8% (90.3–98.9) at 5 years post-vaccination). In JE-vaccine-naïve toddlers, a protective immune response persisted up to at least 5 years in 58.8% (50.9–66.4) after a single-dose administration of JE-CV (GMT 26.7 1/dil; sensitivity analysis).ConclusionsA single-dose of JE-CV as a booster following MBDV administration provided long-lasting immunity. In JE-vaccine-naïve toddlers, despite relatively high seroprotection rates persisting over time, a subsequent booster dose is recommended following a JE-CV primary vaccination for long-term protection.This study was registered on www.clinicaltrials.gov (NCT00621764).