Survival of previously measles-vaccinated and measles-unvaccinated children in an emergency situation:: an unplanned study
Survival of previously measles-vaccinated and measles-unvaccinated children in an emergency situation:: an unplanned study
复制标题
DOI：
10.1097/01.inf.0000083821.33187.b5
复制
发表时间：
2003-09-01
影响因子：
3.6
通讯作者：
Whittle, H
中科院分区：
文献类型：
--
作者：
Aaby, P;Garly, ML;Whittle, H
背景以前的研究表明，标准麻疹疫苗可能会降低死亡率，其降低的死亡人数可能超过死亡率高的地区认为由麻疹感染引起的死亡人数。然而，这些观察结果并没有基于随机试验。在最近的几比比绍战争期间，大多数儿童逃离了比绍市，该国的免疫服务中断了几个月。我们正在进行一项试验，其中儿童在6个月大时被随机接受麻疹疫苗或灭活脊髓灰质炎疫苗。由于战争，许多儿童没有按计划接种9个月大的麻疹疫苗。我们能够监测战争期间和战后的死亡率。结果。该研究包括433名6至11个月大的儿童。15名儿童（3.6%）在战争的前3个月死亡，疫苗接种计划恢复之前，214名麻疹疫苗接种儿童中有4名死亡，219名接受灭活脊髓灰质炎疫苗的儿童中有11名死亡。麻疹疫苗对女孩的影响显著[死亡率比（MR），0.00; 95%置信区间，0.0 - 0.37]，而对男孩没有差异（MR = 1.02; 95%置信区间，0.25 - 3.88）。在控制两组之间差异因素的综合分析中，麻疹疫苗接种儿童的MR为0.30（95%置信限，0.08至0.87）。将观察期延长到1998年底或包括战前时期并没有改变麻疹疫苗对女孩的显著有益效果。据报告，这一组儿童中有22人患过麻疹，其中8人是在战争的3个月内发病的。在分析中排除麻疹病例并没有改变结果;在战争的前3个月，接种麻疹疫苗的儿童的AM为0.28（95%置信限，0.06至0.89）。与以前的观察性研究一致，麻疹疫苗接种与死亡率降低有关，这不能用预防麻疹感染来解释。这种非特异性的有益效果对女孩来说尤其明显。需要进一步的研究来检查在高死亡率环境中非特异性影响的程度。
Background. Previous studies have suggested that standard measles vaccine may reduce mortality by more than the number of deaths thought to be caused by measles infection in areas with high mortality. However, these observations have not been based on randomized trials.Methods. During the recent war in Guinea-Bissau, most children fled from the city of Bissau and immunization services in the country broke down for several months. We were performing a trial in which children were randomized at 6 months of age to receive either measles vaccine or inactivated polio vaccine. Because of the war many children did not receive the dose of measles vaccine planned for 9 months of age. We were able to monitor mortality during the war and after.Results. Included in the study were 433 children 6 to 11 months of age. Fifteen children died (3.6%) during the first 3 months of the war before vaccination programs were resumed, 4 of 214 measles-vaccinated children and 11 of 219 children who had received inactivated polio vaccine. The effect of measles vaccine was marked for girls [mortality rate ratio (MR), 0.00; 95% confidence limits, 0.0 to 0.37], whereas there was no difference for boys (MR = 1.02; 95% confidence limits, 0.25 to 3.88). In a combined analysis controlling for factors that differed between the two groups, the MR for measles-vaccinated children was 0.30 (95% confidence limits, 0.08 to 0.87). Prolonging the period of observation to the end of 1998 or including the prewar period did not modify the significant beneficial effect of measles vaccine for girls. Twenty-two of the children in the cohort were reported to have had measles, 8 cases occurring during the 3 months of the war. Exclusion of measles cases in the analysis did not change the results; children who had received measles vaccine had a AM of 0.28 (95% confidence limits, 0.06 to 0.89) during the first 3 months of the war.Conclusions. Consistent with previous observational studies, measles vaccination was associated with a reduction in mortality that cannot be explained by the prevention of measles infection. This nonspecific beneficial effect was particularly strong for girls. Further studies are needed to examine the extent of nonspecific effects in settings with high mortality.