Erasmus Medical Center, Rotterdam, The Netherlands ; Medicines Evaluation Board, Utrecht, The Netherlands.
PLoS One. 2013 Apr 30;8(4):e63156. doi: 10.1371/journal.pone.0063156. Print 2013.
The aim of the present study was to estimate the effectiveness of the MF59™-adjuvanted influenza A(H1N1)pdm09 vaccine against medically attended influenza-like illness and RT-PCR confirmed influenza in the at-risk population and persons over 60 in the Netherlands.
We conducted a retrospective cohort study in a Dutch based GP medical record database between 30 November 2009 and 1 March 2010 to estimate the vaccine effectiveness against influenza-like illness. Within the cohort we nested a test negative case-control study to estimate the effectiveness against laboratory confirmed influenza.
The crude effectiveness in preventing diagnosed or possible influenza-like illness was 17.3% (95%CI: -8.5%-36.9%). Of the measured covariates, age, the severity of disease and health seeking behaviour through devised proxies confounded the association between vaccination and influenza-like illness. The adjusted vaccine effectiveness was 20.8% (95%CI: -5.4%, 40.5%) and varied significantly by age, being highest in adults up to 50 years (59%, 95%CI: 23%, 78%), and non-detectable in adults over 50 years. The number of cases in the nested case control study was too limited to validly estimate the VE against confirmed influenza.
With our study we demonstrated that the approach of combining a cohort study in a primary health care database with field sampling is a feasible and useful option to monitor VE of influenza vaccines in the future.
本研究旨在评估 MF59 佐剂流感 A(H1N1)pdm09 疫苗在荷兰高危人群和 60 岁以上人群中预防有医疗记录的流感样疾病和 RT-PCR 确诊流感的效果。
我们在荷兰基于全科医生医疗记录数据库中进行了一项回顾性队列研究，以评估疫苗对流感样疾病的有效性。在该队列中，我们嵌套了一项阴性对照病例对照研究，以评估针对实验室确诊流感的效果。
预防确诊或可能的流感样疾病的粗效性为 17.3%（95%CI：-8.5%-36.9%）。在所测量的协变量中，年龄、疾病严重程度和通过设计的替代指标寻求医疗行为混淆了疫苗接种与流感样疾病之间的关联。调整后的疫苗有效性为 20.8%（95%CI：-5.4%，40.5%），且随年龄变化显著，在 50 岁以下的成年人中最高（59%，95%CI：23%，78%），在 50 岁以上的成年人中则无法检测到。嵌套病例对照研究中的病例数量太少，无法有效估计针对确诊流感的 VE。
通过本研究，我们证明了在初级保健数据库中结合队列研究和现场抽样来监测流感疫苗的 VE 是一种可行且有用的方法，将来可以采用这种方法。
