Queen Saovabha Memorial Institute, the Thai Red Cross Society, Bangkok, Thailand; Bureau of General Communicable Diseases, Department of Disease Control, Ministry of Public Health, Thailand.
Division of Infectious Diseases, Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Center of Excellence in Pediatric Infectious Diseases and Vaccines, Chulalongkorn University, Bangkok, Thailand.
Vaccine. 2021 Oct 8;39(42):6206-6209. doi: 10.1016/j.vaccine.2021.08.079. Epub 2021 Sep 21.
Rubella is generally a mild disease, but infection during pregnancy can cause congenital rubella syndrome. Thailand has implemented a two-dose MMR vaccination policy since 2010. This study aimed to describe the seroprevalence rate of rubella among children and adolescents in Thailand. We conducted a cross-sectional study of 132 healthy children (aged 3-9 years) who had received 2 doses of rubella vaccine and 424 adolescents (aged 10-18 years) who were expected to receive at least 1 dose of rubella vaccine. Stored serum samples from healthy children and recently drawn serum samples from adolescents were tested for rubella IgG antibody using a commercial enzyme-linked immunosorbent assay (ELISA) kit (EUROIMMUN). Seroprotection was defined as a rubella IgG level ≥ 10 IU/mL. The rubella seroprevalence rate among children and adolescents who had 2 documented doses of MMR was 97.0% (95 %CI 92.5-99.2%) and 85.4% (95% CI 78.8-90.6%, p < 0.01) respectively. The geometric mean titer of rubella was higher in children, 38.3 (95% CI 33.5-43.9) compared to adolescents, 22.5 (19.4-25.9) IU/mL. We observed an inverse correlation between the rubella titer and time interval from the second rubella containing vaccine dose (R = -0.30, p < 0.01). A 2-dose MMR vaccination course produces a high seroprevalence of rubella immunity in children, which decreases with time, suggesting waning of immunity. Thai clinical trials registry number TCTR20191120001.
风疹通常是一种轻度疾病，但怀孕期间感染可导致先天性风疹综合征。泰国自 2010 年以来实施了两剂麻疹、腮腺炎、风疹联合疫苗（MMR）接种政策。本研究旨在描述泰国儿童和青少年的风疹血清流行率。我们对 132 名接受过两剂风疹疫苗的健康儿童（3-9 岁）和 424 名预计至少接受一剂风疹疫苗的青少年（10-18 岁）进行了横断面研究。使用商业酶联免疫吸附试验（ELISA）试剂盒（EUROIMMUN）检测健康儿童的储存血清样本和青少年的近期血清样本中的风疹 IgG 抗体。将风疹 IgG 水平≥10 IU/mL 定义为血清保护。有 2 剂 MMR 接种记录的儿童和青少年的风疹血清流行率分别为 97.0%（95%CI 92.5-99.2%）和 85.4%（95%CI 78.8-90.6%，p<0.01）。儿童的风疹几何平均滴度较高，为 38.3（95%CI 33.5-43.9），而青少年为 22.5（19.4-25.9）IU/mL。我们观察到风疹滴度与第二剂含风疹疫苗之间的时间间隔呈负相关（R=-0.30，p<0.01）。两剂 MMR 疫苗接种方案可在儿童中产生较高的风疹免疫力血清流行率，但随着时间的推移会降低，表明免疫力减弱。泰国临床试验注册编号 TCTR20191120001。
