Andersen Andreas, Fisker Ane Baerent, Rodrigues Amabelia, Martins Cesario, Ravn Henrik, Lund Najaaraq, Biering-Sørensen Sofie, Benn Christine Stabell, Aaby Peter
Research Centre for Vitamins and Vaccines (CVIVA), Bandim Health Project, Statens Serum Institut, Copenhagen, Denmark.
Bandim Health Project, Indepth Network, Bissau, Guinea-Bissau.
Front Public Health. 2018 Feb 2;6:13. doi: 10.3389/fpubh.2018.00013. eCollection 2018.
A recent WHO review concluded that live BCG and measles vaccine (MV) may have beneficial non-specific effects (NSEs) reducing mortality from non-targeted diseases. NSEs of oral polio vaccine (OPV) were not examined. If OPV vaccination campaigns reduce the mortality rate, it would suggest beneficial NSEs.
Between 2002 and 2014, Guinea-Bissau had 15 general OPV campaigns and other campaigns with OPV plus vitamin A supplementation (VAS), VAS-only, MV, and H1N1 vaccine. In this period, we conducted seven randomized controlled trials (RCTs) with mortality as main outcome.
Within these RCTs, we assessed whether the mortality rate was lower after-campaign than before-campaign. We used Cox models with age as underlying time and further adjusted for low birth-weight, season and time trend in mortality. We calculated the adjusted mortality rate ratio (MRR) for after-campaign vs before-campaign.
The mortality rate was lower after OPV-only campaigns than before, the MRR being 0.81 (95% CI = 0.68-0.95). With each additional dose of campaign-OPV the mortality rate declined further (MRR = 0.87 (95% CI: 0.79-0.96) per dose) (test for trend, = 0.005). No other type of campaign had similar beneficial effects. Depending on initial age and with follow-up to 3 years of age, the number needed to treat with campaign-OPV-only to save one life was between 68 and 230 children.
Bissau had no case of polio infection so the results suggest that campaign-OPV has beneficial NSEs. Discontinuation of OPV-campaigns in low-income countries may affect general child mortality levels negatively.
世界卫生组织最近的一项综述得出结论，卡介苗活疫苗和麻疹疫苗（MV）可能具有有益的非特异性效应（NSEs），可降低非目标疾病的死亡率。口服脊髓灰质炎疫苗（OPV）的非特异性效应未作研究。如果OPV疫苗接种活动能降低死亡率，则表明存在有益的非特异性效应。
2002年至2014年期间，几内亚比绍开展了15次常规OPV疫苗接种活动以及其他包含OPV加维生素A补充剂（VAS）、仅含VAS、MV和H1N1疫苗的活动。在此期间，我们开展了7项以死亡率为主要结局的随机对照试验（RCTs）。
在这些随机对照试验中，我们评估了疫苗接种活动后死亡率是否低于活动前。我们使用以年龄为基础时间的Cox模型，并进一步对低出生体重、季节和死亡率的时间趋势进行了调整。我们计算了活动后与活动前的调整死亡率比（MRR）。
仅开展OPV疫苗接种活动后的死亡率低于活动前，MRR为0.81（95%置信区间=0.68 - 0.95）。每额外增加一剂活动用OPV，死亡率进一步下降（每剂MRR = 0.87（95%置信区间：0.79 - 0.96））（趋势检验，P = 0.005）。没有其他类型的活动有类似的有益效果。根据初始年龄并随访至3岁，仅通过活动用OPV挽救一条生命所需治疗的儿童数量在68至230名之间。
几内亚比绍没有脊髓灰质炎感染病例，因此结果表明活动用OPV具有有益的非特异性效应。低收入国家停止OPV疫苗接种活动可能会对儿童总体死亡率水平产生负面影响。
