Andrade Ana Lucia, Afonso Eliane T, Minamisava Ruth, Bierrenbach Ana Luiza, Cristo Elier B, Morais-Neto Otaliba L, Policena Gabriela M, Domingues Carla M A S, Toscano Cristiana M
Institute of Tropical Pathology and Public Health, Federal University of Goiás, Goiânia, Goiás, Brazil.
Faculty of Medicine, Federal University of Goiás, Goiânia, Goiás, Brazil.
PLoS One. 2017 Sep 7;12(9):e0184204. doi: 10.1371/journal.pone.0184204. eCollection 2017.
Ten-valent pneumococcal conjugate vaccine (PCV10) was introduced in the National Immunization Program of Brazil in March/2010. Although there are recent reports of PCV10 impact on pneumonia hospitalizations, there is still uncertainty regarding the indirect impact in individuals non-targeted by vaccination. We assessed both direct and indirect effect of PCV10 on pneumonia hospitalizations and the impact on the economic burden of pneumonia hospitalizations.
An interrupted time-series analysis was conducted considering monthly rates of pneumonia hospitalizations and comparison groups, in all age-groups, from January/2005-December/2015. We used records of the National Hospitalizations Information System. Observed pneumonia rates in the post-vaccination period (2011–2015) were compared to predicted rates, should PCV10 had not been introduced. Relative percent difference in rates and its 95% confidence interval were estimated. The number of pneumonia hospitalizations averted by vaccination was calculated as the difference between the predicted and observed cumulative number of pneumonia hospitalizations in the post-vaccination period. The impact of PCV10 on economic burden was presented as averted costs of pneumonia hospitalization.
Significant decrease in rates of pneumonia hospitalization was observed in both children targeted by vaccination (17.4%–26.5%; p<0.01), and in age-groups not targeted by vaccination (11.1%–27.1%, in individuals 10–49 years; p<0.01). In contrast, PCV10 introduction did not alter the increasing trends in pneumonia hospitalization among elderly ≥65 years. A total of 457,564 pneumonia hospitalizations was averted in Brazil for individuals aged <50 years, with a total averted costs of BRL 383.2 million (Int$ 225.2 million, and USD 147 million) for the 5 year period after PCV introduction.
Vaccination with PCV10 5 years after its introduction in Brazil was associated with a relevant reduction in pneumonia hospitalization in the target age-groups, with an indirect effect in individuals aged 10–49 years, and significant reduction in associated economic burden. The increasing trends in pneumonia hospitalization rates in the elderly is a matter of concern for public health and should be further investigated.
十价肺炎球菌结合疫苗（PCV10）于2010年3月被纳入巴西国家免疫规划。尽管近期有关于PCV10对肺炎住院率影响的报道，但对于未接种疫苗的个体的间接影响仍存在不确定性。我们评估了PCV10对肺炎住院的直接和间接影响以及对肺炎住院经济负担的影响。
采用中断时间序列分析，考虑2005年1月至2015年12月所有年龄组的肺炎住院月率及对照组。我们使用了国家住院信息系统的记录。将疫苗接种后时期（2011 - 2015年）观察到的肺炎发生率与如果未引入PCV10时预测的发生率进行比较。估计发生率的相对百分比差异及其95%置信区间。接种疫苗避免的肺炎住院病例数计算为疫苗接种后时期预测的和观察到的肺炎住院累积病例数之差。PCV10对经济负担的影响表示为避免的肺炎住院费用。
在接种疫苗的目标儿童中（17.4% - 26.5%；p<0.01）以及未接种疫苗的年龄组（10 - 49岁个体中为11.1% - 27.1%；p<0.01），肺炎住院率均显著下降。相比之下，引入PCV10并未改变65岁及以上老年人肺炎住院率的上升趋势。在巴西，50岁以下个体共避免了457,564例肺炎住院，在引入PCV疫苗后的5年期间，共避免了3.832亿雷亚尔（2.252亿美元，1.47亿美元）的费用。
在巴西引入PCV10五年后，接种疫苗与目标年龄组肺炎住院率的显著降低相关，对10 - 49岁个体有间接影响，并显著降低了相关经济负担。老年人肺炎住院率的上升趋势是公共卫生关注的问题，应进一步调查。
