Youwang Y, Ping W, Feng C
Epidemiological Department, Health Bureau of Jingzhou District, Jingzhou city, 434020, Hubei, People's Republic of China.
Vaccine. 2001 Feb 28;19(15-16):1998-2005. doi: 10.1016/s0264-410x(00)00426-6.
A study of the serological and epidemiological effects of primary immunization with current live attenuated measles vaccine (Hu191) among 503 children aged 6-15 months, was conducted in Jingzhou, Hubei province, China from 1991 to 1998. The results showed that the positive conversion rate of measles IgG was 91.65%, geometric mean titer (GMT) was 1:266.74 and its ratio reaching protective titer was 46.52% at 1 month after first immunization. As time goes on, the above-mentioned indexes reduced rapidly. Short-term and long-term efficacy of 0.2, 0.3 and 0.5 ml measles vaccine was similar. The positive conversion rate, GMT and ratio of protective titer of IgG of different potency measles vaccine were not significantly different, however, latter two indexes showed a tendency to increase gradually with the rise of vaccine potency. The age for primary immunization was a main factor influencing immune response to measles vaccine. Immune efficacy of 6 months old group by primary vaccination was significantly lower than those of > or = 8 months old group. The result indicated it is practicable that infant aged 8 months be vaccinated with measles vaccine in China. Twenty-nine suspected measles cases were reported, out of them, 26 cases were negated in time from December 1991 to November 1998. The study showed that the short-term positive conversion rate of the enzyme immune assay IgG antibody of the Hu191 is higher, but its serological endurance isn't ideal, and its epidemiological effect should be evaluated further.
1991年至1998年在中国湖北省荆州市对503名6至15个月大的儿童接种当前的减毒活麻疹疫苗（Hu191）进行了血清学和流行病学效果研究。结果显示，首次免疫后1个月时麻疹IgG阳性转化率为91.65%，几何平均滴度（GMT）为1:266.74，其达到保护滴度的比例为46.52%。随着时间推移，上述指标迅速下降。0.2、0.3和0.5毫升麻疹疫苗的短期和长期效果相似。不同效力麻疹疫苗的IgG阳性转化率、GMT和保护滴度比例无显著差异，然而，后两个指标有随疫苗效力升高而逐渐增加的趋势。初次免疫年龄是影响麻疹疫苗免疫反应的主要因素。6个月龄组初次接种的免疫效果显著低于≥8月龄组。结果表明在中国8月龄婴儿接种麻疹疫苗是可行的。报告了29例疑似麻疹病例，其中1991年12月至1998年11月期间26例及时排除。研究表明，Hu191酶免疫法IgG抗体的短期阳性转化率较高，但其血清学持久性不理想，其流行病学效果有待进一步评估。
