Janewongwirot Pakpoom, Puthanakit Thanyawee, Anugulruengkitt Suvaporn, Jantarabenjakul Watsamon, Phasomsap Chayapa, Chumket Sompong, Yoksan Sutee, Pancharoen Chitsanu
Division of Infectious Diseases, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Bangkok 10330, Thailand.
Division of Infectious Diseases, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Rama IV Road, Bangkok 10330, Thailand; Research Unit in Pediatric Infectious Diseases and Vaccine, Chulalongkorn University, Bangkok, Thailand.
Vaccine. 2016 Oct 17;34(44):5279-5283. doi: 10.1016/j.vaccine.2016.09.005. Epub 2016 Sep 12.
Japanese Encephalitis chimeric virus vaccine (JE-CV) and SA14-14-2 vaccine are live-attenuated JE vaccines produced from the same virus strain. Data on interchangeability is limited.
To evaluate the immunogenicity and safety of JE-CV booster after primary vaccination with SA14-14-2 vaccine.
This study was an open-label clinical trial in Thai children who had received a primary SA14-14-2 vaccination at 12-24monthsbefore enrollment (ClinicalTrials.gov NCT02602652). JE-CV was administered. A 50% plaque reduction neutralization test (PRNT) against three virus strains; JE-CV, SA-14-14-2andwild-type JE virus was measured before and 28-days post vaccination. The laboratory was performed at PRNT titers ⩾10 (1/dil) were considered seroprotective against JE. Geometric mean titer (GMT) of PRNT was calculated. Adverse events were observed for 28days.
From March 2014 to June 2015, 50 children (64% male) were enrolled. Mean age and duration after primary vaccination was 26.9 (SD 4.6) and 12.8 (SD 2.7) months, respectively. The proportion of participants who had PRNTpre and post-booster vaccination were 92% and 96% against JE-CV virus, 56% and 98% against SA-14-14-2 strain and 70% and 98% against wild-type JE virus, respectively. Solicited injection site reactions including erythema, pain and swelling occurred in 18%, 10% and 4% of subjects, respectively. Four children (8%) had fever (⩾37.7Celsius). Eight children (16%) had adverse events, which were not related to the vaccine.
AJE-CV booster dose is highly immunogenic and safe among children who previously received SA14-14-2 vaccine.
日本脑炎嵌合病毒疫苗（JE-CV）和SA14-14-2疫苗是由同一病毒株生产的减毒活日本脑炎疫苗。关于互换性的数据有限。
评估在接种SA14-14-2疫苗进行初次免疫后接种JE-CV加强针的免疫原性和安全性。
本研究是一项开放标签的临床试验，对象为在入组前12至24个月接受过SA14-14-2初次疫苗接种的泰国儿童（ClinicalTrials.gov标识符：NCT02602652）。接种JE-CV。在接种前和接种后28天，针对三种病毒株（JE-CV、SA-14-14-2和野生型日本脑炎病毒）进行50%蚀斑减少中和试验（PRNT）。实验室检测中，PRNT滴度⩾10（1/稀释度）被认为对日本脑炎具有血清保护作用。计算PRNT的几何平均滴度（GMT）。观察28天的不良事件。
2014年3月至2015年6月，共纳入50名儿童（64%为男性）。初次接种疫苗后的平均年龄和时间分别为26.9（标准差4.6）个月和12.8（标准差2.7）个月。加强针接种前后针对JE-CV病毒、SA-14-14-2毒株和野生型日本脑炎病毒的PRNT阳性参与者比例分别为92%和96%、56%和98%、70%和98%。分别有18%、10%和4%的受试者出现了包括红斑、疼痛和肿胀在内的注射部位反应。4名儿童（8%）出现发热（⩾37.7摄氏度）。8名儿童（16%）出现与疫苗无关的不良事件。
在先前接种过SA14-14-2疫苗的儿童中，JE-CV加强针具有高度免疫原性且安全。
