Navrongo Health Research Centre, Navrongo, Ghana Bandim Health Project, Statens Serum Institut, Copenhagen, Denmark London School of Hygiene and Tropical Medicine, London, UK Bandim Health Project, Indepth Network, Bissau, Guinea-Bissau.
Trop Med Int Health. 2012 Dec;17(12):1492-505. doi: 10.1111/j.1365-3156.2012.03093.x. Epub 2012 Sep 24.
Studies from low-income countries have suggested that routine vaccinations may have non-specific effects on child mortality; measles vaccine (MV) is associated with lower mortality and diphtheria-tetanus-pertussis (DTP) with relatively higher mortality. We used data from Navrongo, Ghana, to examine the impact of vaccinations on child mortality.
Vaccination status was assessed at the initiation of a trial of vitamin A supplementation and after 12 and 24 months of follow-up. Within the placebo group, we compared the mortality over the first 4 months and the full 2 years of follow-up for different vaccination status groups with different likelihoods of additional vaccinations during follow-up. The frequency of additional vaccinations was assessed among children whose vaccination card was seen at 12 and 24 months of follow-up.
Among children with a vaccination card, more than 75% received missing DTP or MV during the first 12 months of follow-up, whereas only 25% received these vaccines among children with no vaccination card at enrollment. Children without a card at enrollment had a significant threefold higher mortality over the 2-year follow-up period than those fully vaccinated. The small group of children with DTP3-4 but no MV at enrollment had lower mortality than children without a card and had the same mortality as fully vaccinated children. In contrast, children with 1-2 DTP doses but no MV had a higher mortality during the first 4 months than children without a card [MRR = 1.65 (0.95, 2.87)]; compared with the fully vaccinated children, they had significantly higher mortality after 4 months [MRR = 2.38 (1.07, 5.30)] and after 2 years [MRR = 2.41 (1.41, 4.15)]. Children with 0-2 DTP doses at enrollment had higher mortality after 4 months (MRR = 1.67 (0.82, 3.43) and after 2 years [MRR = 1.85 (1.16, 2.95)] than children who had all three doses of DTP at enrollment.
As hypothesised, DTP vaccination was associated with higher child mortality than measles vaccination. To optimise vaccination policies, routine vaccinations need to be evaluated in randomised trials measuring the impact on survival.
来自低收入国家的研究表明，常规疫苗接种可能对儿童死亡率产生非特异性影响；麻疹疫苗（MV）与较低的死亡率相关，而白喉-破伤风-百日咳（DTP）疫苗与相对较高的死亡率相关。我们使用加纳纳福隆的数据，研究了疫苗接种对儿童死亡率的影响。
在开始维生素 A 补充试验时以及在 12 个月和 24 个月的随访期间评估了疫苗接种情况。在安慰剂组中，我们比较了在随访的前 4 个月和完整的 2 年随访期间，不同的疫苗接种情况与在随访期间有不同可能性接受额外疫苗接种的死亡率。在 12 个月和 24 个月的随访时看到疫苗接种卡的儿童中，评估了额外接种的频率。
在有疫苗接种卡的儿童中，超过 75%的儿童在随访的前 12 个月期间漏种了 DTP 或 MV，而在登记时没有接种卡的儿童中，只有 25%的儿童接种了这些疫苗。在登记时没有接种卡的儿童在 2 年随访期间的死亡率明显高出三倍。一小部分在登记时接受了 DTP3-4 但未接受 MV 的儿童死亡率低于没有接种卡的儿童，死亡率与完全接种的儿童相同。相比之下，在随访的前 4 个月，仅接受 1-2 剂 DTP 但未接受 MV 的儿童的死亡率高于没有接种卡的儿童[MRR=1.65（0.95，2.87）]；与完全接种的儿童相比，他们在 4 个月后死亡率显著升高[MRR=2.38（1.07，5.30）]，2 年后死亡率升高[MRR=2.41（1.41，4.15）]。在登记时接受 0-2 剂 DTP 的儿童在随访的前 4 个月（MRR=1.67（0.82，3.43））和 2 年（MRR=1.85（1.16，2.95））的死亡率高于在登记时接受所有 3 剂 DTP 的儿童。
正如假设的那样，DTP 疫苗接种与麻疹疫苗接种相比，儿童死亡率更高。为了优化疫苗接种政策，需要在随机试验中评估常规疫苗接种对生存的影响。
