Marshfield Clinic Research Foundation, Marshfield, WI 54449, USA.
Vaccine. 2011 Sep 2;29(38):6558-63. doi: 10.1016/j.vaccine.2011.07.002. Epub 2011 Jul 19.
During the 2007-08 influenza season, we reported an interim vaccine effectiveness (VE) estimate of 44% for preventing medically attended influenza. In this analysis we report results for the entire season and compare them with the interim estimate.
Patients with feverishness, chills, or cough <8 days duration were prospectively recruited over 10 weeks and tested for influenza by real-time reverse transcriptase PCR (rRT-PCR). Case-control analyses were performed using data from patients with rRT-PCR confirmed influenza (cases) and ill patients without influenza (test-negative controls). VE was estimated as 100×(1-adjusted odds ratio) in a logistic regression model adjusting for age, week, and high risk medical condition. A sample of influenza isolates was antigenically characterized.
Influenza was detected by rRT-PCR in 865 (44%) of 1972 patients; 73% were type A and 27% were type B. VE was 37% (95% CI, 22-49%) overall and 44% (95% CI, 27-58%) among participants tested 0-3 days after illness onset. VE was 39% (95% CI, 2-62%) in children 6-59 months old and 37% (95% CI, -2% to 61%) in adults ≥50 years old. VE was 41% (95% CI, 24-53%) for influenza A and 31% (95% CI, 3-51%) for influenza B. All 24 characterized influenza A viruses were antigenically matched to the H3N2 vaccine strain, although 14 viruses exhibited mild antigenic drift. There was a lineage mismatch with the vaccine strain for all 39 characterized influenza B viruses.
The 2007-08 influenza vaccine provided modest protection against medically attended influenza in this population. The interim estimate of VE after 17 days closely approximated the final season VE, supporting the potential use of interim VE estimates while influenza seasons are still in progress.
在 2007-08 年流感季节期间，我们报告了预防有医疗记录的流感的疫苗有效性（VE）的中期估计值为 44%。在本分析中，我们报告了整个季节的结果，并将其与中期估计值进行了比较。
在 10 周的时间内，前瞻性地招募了发热、寒战或咳嗽持续时间<8 天的患者，并通过实时逆转录酶 PCR（rRT-PCR）检测流感。采用患者 rRT-PCR 确认的流感（病例）和未患流感的患病对照（测试阴性对照）的病例对照分析。在 logistic 回归模型中，通过调整年龄、周和高风险医疗状况来估计 VE，VE 估计值为 100×（1-调整后比值比）。对流感分离株进行了抗原特征分析。
在 1972 名患者中，通过 rRT-PCR 检测到流感 865 例（44%）；73%为 A 型，27%为 B 型。总体 VE 为 37%（95%CI，22-49%），发病后 0-3 天就诊的患者 VE 为 44%（95%CI，27-58%）。6-59 个月的儿童 VE 为 39%（95%CI，2-62%），≥50 岁的成年人 VE 为 37%（95%CI，-2%至 61%）。流感 A 的 VE 为 41%（95%CI，24-53%），流感 B 的 VE 为 31%（95%CI，3-51%）。所有 24 种鉴定的流感 A 病毒与 H3N2 疫苗株具有抗原匹配性，尽管 14 种病毒表现出轻微的抗原漂移。所有 39 种鉴定的流感 B 病毒与疫苗株均存在谱系不匹配。
在本人群中，2007-08 年流感疫苗对有医疗记录的流感提供了适度的保护。在 17 天后的中期 VE 估计值与最终季节 VE 非常接近，支持在流感季节仍在进行时使用中期 VE 估计值。
