>Background. Infants aged <12 months are at high risk of hospitalization for influenza. Influenza vaccine is recommended for pregnant women and for most children; however, no vaccine is approved for infants aged !6 months. Effective approaches are needed to protect this vulnerable population. Vaccination of women during pregnancy may protect the infant through transfer of antibodies from the mother. Few studies have examined the effectiveness of this strategy, and those studies produced mixed results.>Methods. In a matched case-control study, case patients were infants aged <12 months admitted to a large urban hospital in the northeastern United States because of laboratory-confirmed influenza from 2000 to 2009. For each case, we enrolled 1 or 2 control subjects who were infants who tested negative for influenza and matched cases by date of birth and date of hospitalization (within 4 weeks). Vaccine effectiveness was calculated on the basis of matched odds ratios and was adjusted for confounding.>Results. The mothers of 2 (2.2%) of 91 case subjects and 31 (19.9%) of 156 control subjects aged <6 months, and 1 (4.6%) of 22 case subjects and 2 (5.6%) of 36 control subjects aged ⩾6 months, had received influenza vaccine during pregnancy. The effectiveness of influenza vaccine given to mothers during pregnancy in preventing hospitalization among their infants, adjusted for potential confounders, was 91.5% (95% confidence interval [CI], 61.7%–98.1%; P = .001) for infants aged <6 months. The unadjusted effectiveness was 90.7% (95% CI, 59.9%–97.8%; P = .001).>Conclusions. Influenza vaccine given to pregnant women is 91.5% effective in preventing hospitalization of their infants for influenza in the first 6 months of life.
展开▼
机译:>背景 strong>。12岁以下的婴儿患流感的住院风险很高。建议孕妇和大多数儿童使用流感疫苗;但是,未批准6个月以上婴儿的疫苗。需要采取有效措施来保护这一弱势群体。孕妇在怀孕期间进行疫苗接种可通过从母亲转移抗体来保护婴儿。很少有研究检查这种策略的有效性,并且这些研究得出的结果参差不齐。>方法 strong>。在匹配的病例对照研究中,病例患者为<12个月内在一家大型城市医院住院的婴儿。在2000年至2009年期间,由于实验室确诊的流感而在美国东北部地区进行了研究。对于每例病例,我们招募了1例或2例对照受试者,这些婴儿的流感检测呈阴性,并按出生日期和住院日期(4周内)匹配了病例。 >结果 strong>。91名病例中的2名(2.2%)和156名< 6个月大的6个月大的孕妇中有6个月接种了流感疫苗,其中22名病例中有1名(4.6%)和36名年龄在6个月以下的36名对照组中有2名(5.6%)。校正了潜在混杂因素后,孕妇在怀孕期间接种流感疫苗预防婴儿住院的有效性为91.5%(95%置信区间[CI],61.7%–98.1%; P = .001),小于6岁的婴儿个月。未经调整的有效性为90.7%(95%CI,59.9%–97.8%; P = .001)。>结论。 strong>孕妇使用流感疫苗预防婴儿因流感住院的有效率为91.5%。在生命的头6个月。
展开▼