Paunio M, Hedman K, Davidkin I, Valle M, Heinonen O P, Leinikki P, Salmi A, Peltola H
Department of Public Health, University of Helsinki, Finland.
Epidemiol Infect. 2000 Apr;124(2):263-71. doi: 10.1017/s0950268899003222.
Failure to seroconvert (primary vaccine failure) is believed to be the principal reason (approx. > 95%) why some vaccinees remain susceptible to measles and is often attributed to the persistence of maternal antibodies in children vaccinated at a young age. Avidity testing is able to separate primary from secondary vaccine failures (waning and/or incomplete immunity), but has not been utilized in measles epidemiology. Low-avidity (LA) and high-avidity (HA) virus-specific IgG antibodies indicate primary and secondary failure, respectively. Measles vaccine failures (n = 142; mean age 10.1 years, range 2-22 years) from an outbreak in 1988-9 in Finland were tested for measles-virus IgG avidity using a protein denaturating EIA. Severity of measles was recorded in 89 failures and 169 non-vaccinees (mean age 16.2 years, range 2-22 years). The patients with HA antibodies (n = 28) tended to have clinically mild measles and rapid IgG response. Among failures vaccinated at < 12, 12-15 and > 15 months of age with single doses of Schwarz-strain vaccine in the 1970s, 50 (95% CI 1-99), 36 (CI 16-56) and 25% (CI 8-42) had HA antibodies, respectively. When a single measles, mumps and rubella (MMR) vaccine had been given after 1982 at 15 months of age, only 7% (CI 0-14) showed HA antibodies. Omitting re-vaccinees and those vaccinated at < 15 months, Schwarz-strain recipients had 3.6 (CI 1.1-11.5) higher occurrence of HA responses compared to MMR recipients. Apart from one municipality, where even re-vaccinees had high risk of primary infection, 89% (CI 69 to approximately 100) of the infected re-vaccinees had an HA response. Secondary measles-vaccine failures are more common than was more previously thought, particularly among individuals vaccinated in early life, long ago, and among re-vaccinees. Waning immunity even among individuals vaccinated after 15 months of age, without the boosting effect of natural infections should be considered a relevant possibility in future planning of vaccination against measles.
血清阳转失败（原发性疫苗失败）被认为是部分接种疫苗者仍易感染麻疹的主要原因（约>95%），这通常归因于年幼接种疫苗儿童体内母体抗体的持续存在。亲和力检测能够区分原发性和继发性疫苗失败（免疫减弱和/或不完全免疫），但尚未应用于麻疹流行病学研究。低亲和力（LA）和高亲和力（HA）病毒特异性IgG抗体分别表明原发性和继发性失败。对1988 - 1989年芬兰一次麻疹暴发中的142例麻疹疫苗接种失败病例（平均年龄10.1岁，范围2 - 22岁），使用蛋白质变性酶免疫测定法检测麻疹病毒IgG亲和力。记录了89例疫苗接种失败病例和169例未接种疫苗者（平均年龄16.2岁，范围2 - 22岁）的麻疹严重程度。具有HA抗体的患者（n = 28）往往患临床症状较轻的麻疹且IgG反应迅速。在20世纪70年代分别于<12、12 - 15和>15月龄接种单剂施瓦茨株疫苗的疫苗接种失败病例中，分别有50%（95%CI 1 - 99）、36%（CI 16 - 56）和25%（CI 8 - 42）具有HA抗体。1982年后15月龄接种一剂麻疹、腮腺炎和风疹（MMR）联合疫苗的病例中，只有7%（CI 0 - 14）显示有HA抗体。排除再次接种者和<15月龄接种者后，施瓦茨株疫苗接种者HA反应发生率比MMR疫苗接种者高3.6倍（CI 1.1 - 11.5）。除了一个市镇，即使再次接种者也有原发性感染的高风险外，89%（CI 69至约100）的感染再次接种者有HA反应。继发性麻疹疫苗接种失败比以前认为的更常见，特别是在早年、很久以前接种疫苗的个体以及再次接种者中。即使在15月龄后接种疫苗且没有自然感染增强作用的个体中，免疫减弱也应被视为未来麻疹疫苗接种规划中的一个相关可能性。
