Department of Preventive Medicine, Colorado School of Public Health, Aurora, CO 80231, USA.
Pediatr Infect Dis J. 2011 Jul;30(7):562-5. doi: 10.1097/INF.0b013e31820bb482.
The 2009 pandemic H1N1 influenza virus emerged in March 2009 and spread rapidly, causing many thousands of deaths worldwide. A case-control study of 60 Mexican adults with H1N1 suggested that the seasonal influenza vaccine protected against H1N1 infection (odds ratio [OR], 0.27; 95% confidence interval [CI], 0.11-0.66), but subsequent studies have had varied results and few have addressed this question in children. The objective of this study was to evaluate the effect of 2008-2009 seasonal influenza vaccination on pandemic H1N1 infection in children.
Cases (n = 165) were Kaiser Permanente Colorado inpatients and outpatients aged between 18 months and 18 years, with laboratory-confirmed pandemic H1N1 infection from May to November 2009. Controls (n = 660) were pediatric Kaiser Permanente members without documented H1N1 infection who were matched by age and gender. Seasonal influenza vaccination status was recorded for all cases and controls; conditional logistic regression analyses were used to calculate matched odds ratios.
Cases were more likely than controls to have underlying chronic health conditions (45% vs. 21%, P < 0.0001). Pandemic H1N1 cases were neither more nor less likely to have received the 2008-2009 seasonal influenza vaccine (OR, 1.31; 95% CI, 0.92-1.88). After adjustment for chronic medical conditions and health-seeking behavior, H1N1 cases were as likely as controls to have received the 2008-2009 seasonal influenza vaccine (OR, 1.08; 95% CI, 0.75-1.57).
There was no overall association--either protection or risk--between seasonal influenza vaccination and medically attended pandemic H1N1 infection in children. These results have important implications for understanding influenza immunity and future public health efforts to prevent pandemic influenza.
2009 年大流行的 H1N1 流感病毒于 2009 年 3 月出现并迅速传播，导致全球数千人死亡。一项针对 60 名墨西哥成年人的 H1N1 病例对照研究表明，季节性流感疫苗可预防 H1N1 感染（比值比[OR]，0.27；95%置信区间[CI]，0.11-0.66），但随后的研究结果不一，且很少有研究在儿童中探讨这一问题。本研究旨在评估 2008-2009 年季节性流感疫苗接种对儿童大流行 H1N1 感染的影响。
病例（n=165）为科罗拉多州凯撒永久医疗机构的住院和门诊患者，年龄在 18 个月至 18 岁之间，2009 年 5 月至 11 月实验室确诊为大流行 H1N1 感染。对照组（n=660）为儿科凯撒永久医疗机构成员，无记录的 H1N1 感染，年龄和性别与病例匹配。所有病例和对照均记录季节性流感疫苗接种情况；采用条件逻辑回归分析计算匹配比值比。
病例组比对照组更有可能存在基础慢性健康状况（45%比 21%，P<0.0001）。大流行 H1N1 病例组既不比对照组更有可能也不比对照组更不可能接种 2008-2009 年季节性流感疫苗（OR，1.31；95%CI，0.92-1.88）。调整慢性疾病状况和寻医行为后，H1N1 病例组与对照组接种 2008-2009 年季节性流感疫苗的可能性相当（OR，1.08；95%CI，0.75-1.57）。
季节性流感疫苗接种与儿童有医疗记录的大流行 H1N1 感染之间没有总体关联——无论是保护还是风险。这些结果对理解流感免疫和未来预防大流行流感的公共卫生工作具有重要意义。
