Institute for Hygiene and Microbiology, University of Wuerzburg, Josef Schneider-Strasse 2, 97080, Wuerzburg, Germany.
J Occup Med Toxicol. 2013 Mar 4;8(1):4. doi: 10.1186/1745-6673-8-4.
Occupational exposure to live meningococci can potentially cause invasive meningococcal disease in laboratory staff. While, until recently, immunization with quadrivalent polysaccharide vaccine represented one cornerstone of protection, data on long-term persistence of antibodies in adults remain scarce.
We analyzed the relationship of antibody levels and time following quadrivalent polysaccharide vaccination (Mencevax® ACWY, GlaxoSmithKline) in a cross-sectional sample of 20 laboratory workers vaccinated at ages between 16.4 to 40.7 years from Germany. Sera were obtained 0.4 to 158.5 (median 35.3) months after vaccination. At the time of sampling, laboratory workers had been regularly exposed to meningococci for periods between 3.2 to 163.8 (median 41.2) months. Serum bactericidal assay (SBA) with rabbit complement and a microsphere-based flow analysis method were used to determine bactericidal titers and concentrations of IgG, respectively, against serogroups A, C, W135, and Y. Decay of antibodies was modeled using linear regression. Protective levels were defined as SBA titers ≥ 8.
Half-lives of SBA titers against serogroups A, C, W135, and Y were estimated at 27.4, 21.9, 18.8, and 28.0 months, respectively. Average durations of protection were estimated at 183.9, 182.0, 114.6, and 216.4 months, respectively. Inter-individual variation was high; using lower margins of 95% prediction intervals, minimal durations of protection against serogroups A, C, W135 and Y were estimated at 33.5, 24.6, 0.0, and 55.1 months, respectively. The proportion of staff with protective SBA titers against W135 (65.0%) was significantly lower than proportions protected against A (95.0%), C (94.7%), and Y (95.0%). Consistently, geometric mean titer (97.0) and geometric mean concentration of IgG (2.1 μg/ml) was lowest against serogroup W135. SBA titers in a subset of individuals with incomplete protection rose to ≥ 128 (≥ 8 fold) after reimmunization with a quadrivalent glycoconjugate vaccine.
The average duration of protection following immunization with a quadrivalent polysaccharide vaccine in adults was ≥ 115 months regardless of serogroup. A substantial proportion (approximately 23% according to our decay model) of adult vaccinees may not retain protection against serogroup W135 for five years, the time suggested for reimmunization.
职业接触活脑膜炎球菌可能会导致实验室工作人员发生侵袭性脑膜炎球菌病。虽然，直到最近，接种四价多糖疫苗仍然是保护的一个基石，但成年人抗体长期持续存在的数据仍然很少。
我们分析了德国 20 名实验室工作人员接种四价多糖疫苗（Mencevax® ACWY，葛兰素史克）后 0.4 至 158.5 个月（中位数 35.3 个月）血清抗体水平与时间的关系。接种疫苗时，实验室工作人员已经定期接触脑膜炎球菌 3.2 至 163.8 个月（中位数 41.2 个月）。使用兔补体血清杀菌试验（SBA）和基于微球的流动分析方法分别测定针对血清群 A、C、W135 和 Y 的杀菌滴度和 IgG 浓度。使用线性回归模型来模拟抗体的衰减。保护性水平定义为 SBA 滴度≥8。
血清群 A、C、W135 和 Y 的 SBA 滴度半衰期估计分别为 27.4、21.9、18.8 和 28.0 个月。估计的平均保护期分别为 183.9、182.0、114.6 和 216.4 个月。个体间差异很大；使用 95%预测区间下限，血清群 A、C、W135 和 Y 的最低保护期估计分别为 33.5、24.6、0.0 和 55.1 个月。对 W135 具有保护性 SBA 滴度的工作人员比例（65.0%）明显低于对 A（95.0%）、C（94.7%）和 Y（95.0%）的保护比例。一致地，血清群 W135 的 SBA 滴度（97.0）和 IgG 几何平均浓度（2.1μg/ml）最低。在一组不完全保护的个体中，再次接种四价糖结合疫苗后，SBA 滴度升高至≥128（≥8 倍）。
成年人接种四价多糖疫苗后的平均保护期≥115 个月，与血清群无关。根据我们的衰减模型，大约 23%的成年疫苗接种者可能无法在五年内保留对血清群 W135 的保护，这是建议再次免疫的时间。
