北京市石景山区健康人群甲流抗体水平及疫苗免疫效果

Serum level of antibodies against influenza A (H1N1) at baseline and after vaccination among healthy people in Shijingshan district of Beijing in 2009

目的了解北京市石景山区健康人群甲型H1N1流感抗体水平及疫苗的免疫效果。方法随机选取10个年龄组共236人作为人群抗体水平监测对象,其中83人作为疫苗免疫效果评估对象,共采集319份静脉血采用血凝抑制试验测定H1抗体。结果健康人群中抗体阳性率为31.36%,几何平均滴度(GMT)为1∶17.22,各年龄组间差异有统计学意义(χ2=57.43,P<0.001;F=9.12,P<0.001),20～59岁组水平最低,职业分布与年龄分布相一致。监测免疫后人群83人,抗体阳性率为95.18%,GMT为1∶184.41,显著高于免疫前水平(χ2=70.58,P<0.001;F=17.59,P<0.001)。结论石景山区人群已具有一定的甲型H1N1流感保护性抗体水平,甲型H1N1流感疫苗具有良好的流行病学保护效果。

Objective To understand serum level of antibody against influenza A （H1N1） virus at baseline and after vaccination among healthy people in Shijingshan district of Beijing to provide scientific basis for further promotion of its vaccination. Methods A total of 236 people at various age groups were selected for the study, 83 for evaluating immunological effects after vaccination. In total, 319 serum specimens were collected to detect hemagglutination-inhibition （HI） antibody against 2009 influenza A （H1N1） virus.Results Prevalence of the protective antibody in healthy people was 31.36 percent with geometric mean titer （GMT） of 1∶17.22 before vaccination. There was significant differences in prevalence and GMT of antibody against influenza A （H1N1） among varied age groups （χ2=70.58, P0.001 and F=17.59, P0.001, respectively）, with the lowest prevalence and GMT at groups of 20~59 years old. Distribution of serum prevalence of influenza A （H1N1） antibody by occupation was consistent with that by age. Prevalence of the antibody and GMT were 95.18 percent and 1∶184.41, respectively after vaccination, significantly higher than those before it （χ2=70.58, P0.001 and F=17.59, P0.001, respectively）.Conclusion About 31 percent of healthy people in Shijingshan district show serum protective antibody against 2009 influenza A （H1N1） virus before vaccination, and a better immunological effect of influenza A （H1N1） vaccine has been observed after vaccination.