Can changes in malaria transmission intensity explain prolonged protection and contribute to high protective efficacy of intermittent preventive treatment for malaria in infants?
Can changes in malaria transmission intensity explain prolonged protection and contribute to high protective efficacy of intermittent preventive treatment for malaria in infants?
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DOI：
10.1186/1475-2875-7-54
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发表时间：
2008-04-03
期刊：
影响因子：
3
通讯作者：
Chandramohan, Daniel
中科院分区：
文献类型：
--
作者：
Gosling, Roly D.;Ghani, Azra C.;Chandramohan, Daniel
背景资料：婴儿间歇性预防性（或假定性）治疗（IPTi），即对婴儿给予治疗性抗疟剂量，无论他们是否已知感染，被认为是疟疾控制的新战略。使用磺胺嘧啶-乙胺嘧啶（SP）进行IPTi的六项试验中的五项显示出对临床疟疾的保护效力（PE）在20.1-33.3%的范围内，而一项Ifakara研究显示出58.6%的保护效力。通过比较数学模型的输出与六个模型的数据，研究了可以解释IPTi报告的PE差异的可能机制。已发表的IPTi试验。结果：在稳定传播下，除Ifakara研究外，该模型预测的IPTi PE与所有研究中观察到的PE相当（平均预测PE与观察到的PE之比为1.02，范围为0.39-1.59）。当模型中包括研究期间感染发生率的降低时，IPTi的预测PE增加并延长到生命的第二年，如Ifakara研究中所观察到的那样。研究期间疟疾传播的减少可能部分解释了不同地点之间观察到的IPTi PE的差异，以及在Ifakara中观察到的保护期延长到生命的第二年。study.这一发现表明，在传播减少的情况下，干预措施持续有益，这可能解释了为什么在大规模的经杀虫剂处理的蚊帐试验中，临床疟疾没有反弹。
Background: Intermittent preventive (or presumptive) treatment of infants (IPTi), the administration of a curative anti-malarial dose to infants whether or not they are known to be infected, is being considered as a new strategy for malaria control. Five of the six trials using sulphadoxine-pyrimethamine (SP) for IPTi showed protective efficacies (PEs) against clinical malaria ranging from 20.1-33.3% whilst one, the Ifakara study, showed a protective efficacy of 58.6%.Materials and methods: The possible mechanisms that could explain the differences in the reported PE of IPTi were examined by comparing output from a mathematical model to data from the six published IPTi trials.Results: Under stable transmission, the PE of IPTi predicted by the model was comparable with the observed PEs in all but the Ifakara study (ratio of the mean predicted PE to that observed was 1.02, range 0.39-1.59). When a reduction in the incidence of infection during the study was included in the model, the predicted PE of IPTi increased and extended into the second year of life, as observed in the Ifakara study.Conclusion: A decrease in malaria transmission during the study period may explain part of the difference in observed PEs of IPTi between sites and the extended period of protection into the second year of life observed in the Ifakara study. This finding of continued benefit of interventions in settings of decreasing transmission may explain why rebound of clinical malaria was absent in the large scale trials of insecticide-treated bed nets.