Palmu Arto A, Kilpi Terhi M, Rinta-Kokko Hanna, Nohynek Hanna, Toropainen Maija, Nuorti J Pekka, Jokinen Jukka
Department of Health Protection, National Institute for Health and Welfare, Tampere, Finland;
Department of Health Protection, National Institute for Health and Welfare, Helsinki, Finland;
Pediatrics. 2015 Jul;136(1):e22-7. doi: 10.1542/peds.2015-0458. Epub 2015 Jun 15.
Ten-valent pneumococcal conjugate vaccine (PCV10) was earlier shown to reduce clinically suspected, non-laboratory-confirmed invasive pneumococcal disease (IPD) in a cluster-randomized trial (the Finnish Invasive Pneumococcal disease trial). PCV10 was introduced into the Finnish national vaccination program in September 2010 using a 3-dose schedule. We evaluated the impact of PCV10 on clinically suspected IPD among vaccine-eligible children in a population-based nationwide study.
The target cohort eligible for vaccination program (children born June 2010-September 2013) was compared with 2 season- and age-matched (ages 3-42 months) reference cohorts before PCV10 introduction. The trial period (January 2009-August 2010) was excluded. Hospitals' inpatient and outpatient discharge notifications with International Classification of Diseases, 10th Revision, diagnoses compatible with IPD (A40.3/B95.3/G00.1/M00.1) and unspecified sepsis (A40.9/A41.9/A49.9/G00/G00.9/I30.1/M00/M00.9/B95.5) were collected from the national Care Register. Laboratory-confirmed IPD cases were excluded. Rates of register-based non-laboratory-confirmed IPD (or unspecified sepsis) before and after PCV10 implementation were calculated.
The rate of register-based non-laboratory-confirmed IPD episodes was 32 in 100 000 person-years in the vaccine-eligible target cohort and 94 in the combined reference cohorts. Relative rate reduction was 66% (95% confidence interval: 59-73) and absolute rate reduction 62 in 100 000 person-years. For the more sensitive case definition of register-based non-laboratory-confirmed IPD or unspecified sepsis, the relative rate reduction was 34% (95% confidence interval 29-39), but the absolute reduction was as high as 122 in 100 000 person-years.
This is the first report demonstrating nationwide PCV impact on clinically suspected IPD during routine vaccination program. The large absolute rate reductions observed have major implications for cost-effectiveness of PCVs.
在一项整群随机试验（芬兰侵袭性肺炎球菌病试验）中，十价肺炎球菌结合疫苗（PCV10）早期显示可降低临床疑似、未经实验室确诊的侵袭性肺炎球菌病（IPD）。2010年9月，PCV10以三剂次接种程序被纳入芬兰国家疫苗接种计划。在一项基于全国人群的研究中，我们评估了PCV10对符合疫苗接种条件儿童的临床疑似IPD的影响。
将符合疫苗接种计划的目标队列（2010年6月至2013年9月出生的儿童）与PCV10引入前两个按季节和年龄匹配（3至42个月）的参照队列进行比较。试验期（2009年1月至2010年8月）被排除。从国家医疗保健登记处收集国际疾病分类第十版诊断为与IPD相符（A40.3/B95.3/G00.1/M00.1）以及未明确的败血症（A40.9/A41.9/A49.9/G00/G00.9/I30.1/M00/M00.9/B95.5）的医院住院和门诊出院通知。排除实验室确诊的IPD病例。计算PCV10实施前后基于登记的非实验室确诊IPD（或未明确的败血症）发病率。
在符合疫苗接种条件的目标队列中，基于登记的非实验室确诊IPD发病率为每10万人年32例，在合并的参照队列中为每10万人年94例。相对发病率降低66%（95%置信区间：59 - 73），绝对发病率降低为每10万人年62例。对于基于登记的非实验室确诊IPD或未明确的败血症更敏感的病例定义，相对发病率降低34%（95%置信区间29 - 39），但绝对降低高达每10万人年122例。
这是首份证明在常规疫苗接种计划期间全国范围内PCV对临床疑似IPD有影响的报告。观察到的大幅绝对发病率降低对PCV的成本效益有重大影响。
