北京市房山区甲型H1N1流感抗体血清流行病学调查

 目的 了解北京市房山区人群甲型H1N1流感免疫水平,为完善该区甲型H1N1流感疫情防控措施提供科学依据.方法 选择房山区常住人口784名,按照年龄组进行分层和问卷调查,采集血清标本进行甲型H1N1流感病毒血凝抑制(hemagglutination-inhibition,HI)抗体检测,比较不同人群甲型H1N1流感保护性抗体阳性率和抗体几何平均滴度(geometric mean titer,GMT).结果 784名调查对象甲型H1N1抗体阳性率为40.9%(321/784),抗体几何平均滴度为1∶ 18.39.6~15岁年龄组抗体阳性率最高(57.5%),其次是16~24岁年龄组(54.7%),而≥60岁年龄组HI抗体阳性率最低(21.2%).非条件多因素logistic回归分析显示,年龄及接种甲型H1N1流感疫苗与HI抗体阳性呈显著性相关.结论 房山区有超过40%的人群具有甲型H1N1流感保护性抗体,普通人群中已经建立一定的免疫屏障.

A serological epidemiological investigation of influenza A (H1N1) in Fangshan District of Beijing

Objective To investigate the immunological level of population against influenza A （ H1 N1 ） in Fangshan District of Beijing in order to evaluate the trend of the disease and provide data for vaccination policy in high - risk population. Methods Between January 20, 2010 and January 24, 2010, subjects were randomly selected from local residents and stratified in five age groups. A questionnaire survey was conducted and serum samples were collected to detect the hemagglutination - inhibition （ HI ） antibody a- gainst influenza A （ H1 N1 ）. The antibody levels of different populations were determined by rates of protective antibody and geometric mean titer （GMT）. Results Seven hundred and eighty four subjects were enrolled in this survey. The positive rate of protective antibody to A/H1N1 in the whole population in Fangshan District was 40.9% （321/784） , and the average level of HI antibody was 1 ： 18.39. In the group aged 6 to 15, the level of HI antibody was the highest （ sero - positive rate =57.5% ） , the next was 54.7% in the age group of 25 -59 years, and the positive rate in the age group of ≥60 was the lowest （21.2%）. By multivariate logistic regression analysis, such factors as age and the rate of pandemic （H1 N1 ） vaccination were significantly associated with sero- positivity of HI antibody to the influenza A （ H1 N1 ） virus. Conclusions Over 40% of the population in Fangshan District show protective antibody against influenza A（ H1N1 ） virus, indicating to some extent that the immunological defense against this disease has been formed.