Belshe Robert B, Edwards Kathryn M, Vesikari Timo, Black Steven V, Walker Robert E, Hultquist Micki, Kemble George, Connor Edward M
Saint Louis University Health Sciences Center, St. Louis, USA.
N Engl J Med. 2007 Feb 15;356(7):685-96. doi: 10.1056/NEJMoa065368.
Universal vaccination of children 6 to 59 months of age with trivalent inactivated influenza vaccine has recently been recommended by U.S. advisory bodies. To evaluate alternative vaccine approaches, we compared the safety and efficacy of intranasally administered live attenuated influenza vaccine with those of inactivated vaccine in infants and young children.
Children 6 to 59 months of age, without a recent episode of wheezing illness or severe asthma, were randomly assigned in a 1:1 ratio to receive either cold-adapted trivalent live attenuated influenza vaccine (a refrigeration-stable formulation of live attenuated intranasally administered influenza vaccine) or trivalent inactivated vaccine in a double-blind manner. Influenza-like illness was monitored with cultures throughout the 2004-2005 influenza season.
Safety data were available for 8352 children, and 7852 children completed the study according to the protocol. There were 54.9% fewer cases of cultured-confirmed influenza in the group that received live attenuated vaccine than in the group that received inactivated vaccine (153 vs. 338 cases, P<0.001). The superior efficacy of live attenuated vaccine, as compared with inactivated vaccine, was observed for both antigenically well-matched and drifted viruses. Among previously unvaccinated children, wheezing within 42 days after the administration of dose 1 was more common with live attenuated vaccine than with inactivated vaccine, primarily among children 6 to 11 months of age; in this age group, 12 more episodes of wheezing were noted within 42 days after receipt of dose 1 among recipients of live attenuated vaccine (3.8%) than among recipients of inactivated vaccine (2.1%, P=0.076). Rates of hospitalization for any cause during the 180 days after vaccination were higher among the recipients of live attenuated vaccine who were 6 to 11 months of age (6.1%) than among the recipients of inactivated vaccine in this age group (2.6%, P=0.002).
Among young children, live attenuated vaccine had significantly better efficacy than inactivated vaccine. An evaluation of the risks and benefits indicates that live attenuated vaccine should be a highly effective, safe vaccine for children 12 to 59 months of age who do not have a history of asthma or wheezing. (ClinicalTrials.gov number, NCT00128167 [ClinicalTrials.gov].).
美国咨询机构最近建议对6至59个月大的儿童普遍接种三价灭活流感疫苗。为评估其他疫苗接种方法，我们比较了鼻内接种减毒活流感疫苗与灭活疫苗在婴幼儿中的安全性和有效性。
将6至59个月大、近期无喘息疾病或重度哮喘发作的儿童按1:1比例随机分组，以双盲方式接受冷适应三价减毒活流感疫苗（一种冷藏稳定的鼻内接种减毒活流感疫苗制剂）或三价灭活疫苗。在整个2004 - 2005流感季节，通过培养监测流感样疾病。
有8352名儿童的安全数据可用，7852名儿童按方案完成了研究。接种减毒活疫苗组的培养确诊流感病例比接种灭活疫苗组少54.9%（153例对338例，P<0.001）。对于抗原匹配良好和发生抗原漂移的病毒，减毒活疫苗的疗效均优于灭活疫苗。在既往未接种疫苗的儿童中，接种第1剂疫苗后42天内喘息在接种减毒活疫苗的儿童中比接种灭活疫苗的儿童更常见，主要是在6至11个月大的儿童中；在这个年龄组中，接种减毒活疫苗的儿童在接种第1剂疫苗后42天内出现喘息的次数比接种灭活疫苗的儿童多12次（3.8%对2.1%，P = 0.076）。6至11个月大的接种减毒活疫苗儿童在接种疫苗后180天内任何原因的住院率高于该年龄组接种灭活疫苗的儿童（6.1%对2.6%，P = 0.002）。
在幼儿中，减毒活疫苗的疗效明显优于灭活疫苗。对风险和益处的评估表明，减毒活疫苗对于无哮喘或喘息病史的12至59个月大儿童应是一种高效、安全的疫苗。（临床试验注册号，NCT00128167 [ClinicalTrials.gov]。）
