摘要目的:评价≥60岁老年人再接种23价肺炎球菌多糖疫苗（PPV23）的免疫原性和安全性。方法:招募≥60岁有1剂次PPV23免疫史者作为再接种组，无肺炎球菌疫苗免疫史者作为首次接种组，两组研究对象接种1剂次PPV23，于接种前后28~40 d采集血标本，使用ELISA检测抗特定血清型肺炎链球菌荚膜多糖免疫球蛋白G浓度，监测研究对象接种后30 d内的安全性。结果:免疫前23个血清型抗体几何平均浓度（GMC）再接种组（0.73~13.73 μg/ml）高于首次接种组（0.39~7.53 μg/ml），再接种组免疫后GMC（1.42~31.65 μg/ml）高于免疫前（0.73~13.73 μg/ml），首次接种组免疫后GMC（1.62~43.76 μg/ml）高于免疫前（0.39~7.53 μg/ml）；再接种组几何平均增长倍数（2.16~3.60）低于首次接种组（3.86~16.13）；再接种组抗体平均2倍增长率［53.68%（95% CI：52.30%~55.06%）］低于首次接种组［93.16%（95% CI：92.18%~94.15%）］，差异均有统计学意义（ P<0.001）。免疫后13个血清型抗体GMC首次接种组高于再接种组（ P<0.001），10个血清型抗体GMC两组间差异均无统计学意义（ P>0.05）。再接种组和首次接种组局部不良事件发生率分别为19.20%和13.27%（ P=0.174）。 结论:≥60岁老年人接种1剂次PPV23间隔5年后抗体水平仍高于未接种者；首次接种5年后抗体水平有所下降，再接种1剂次PPV23抗体水平可快速提升，但总体免疫反应低于首次接种者；再接种PPV23具有良好的安全性。

abstractsObjective:To evaluate the immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine (PPV23) in elderly people aged ≥60 years.Methods:The elderly aged ≥60 years with 1 dose of PPV23 vaccination were selected as revaccination group and those without history of pneumococcal vaccine immunization were selected as the first vaccination group. One dose of PPV23 was administered to both groups, and the first blood samples were collected before vaccination while the second blood samples were collected on day 28-40 after vaccination. ELISA was used to detect the concentrations of anti-specific serotype Streptococcus pneumoniae podocyte polysaccharide immunoglobulin G, and the safety of the vaccination was evaluated after 30 days.Results:The geometric mean concentration (GMC) of antibody to 23 serotypes before the vaccination (0.73-13.73 μg/ml) was higher in revaccination group than in the first vaccination group (0.39-7.53 μg/ml), the GMC after the vaccination (1.42-31.65 μg/ml) was higher than that before the vaccination (0.73-13.73 μg/ml) in the revaccination group, and the GMC after the vaccination (1.62-43.76 μg/ml) was higher than that before the vaccination (0.39-7.53 μg/ml) in the first vaccination group; the geometric mean growth multiple in revaccination group (2.16-3.60) was lower than that in the first vaccination group (3.86-16.13); The mean 2-fold antibody growth rate was lower in revaccination group (53.68%, 95% CI: 52.30%-55.06%) than in the first vaccination group (93.16%, 95% CI: 92.18%- 94.15%), all differences were significant ( P<0.001). After the vaccination, 13 serotypes of GMC were higher in the first vaccination group than in revaccination group ( P<0.001), the differences were not significant for 10 serotypes of GMC ( P>0.05). The incidence of local adverse reaction was 19.20% and 13.27% in revaccination group and the first vaccination group, respectively ( P=0.174). Conclusions:The antibody level in ≥60 years people who received one dose of PPV23 after a 5-year interval was still higher than that in unvaccinated people. The antibody level decreased after 5 years of the first vaccination, and the antibody level could be rapidly increased by one more dose vaccination, but the overall immune response was lower than that of the first vaccination; revaccination with PPV23 has a good safety.