Establishing the Feasibility of using daily Dried Blood Spots (DBS) to study the Natural History of Low-density Asymptomatic Malaria Infection to Inform Malaria Elimination

摘要 在流行人群中有相当数量的低密度疟原虫感染， 这种类型的感染比例似乎随着传播强度的降低而增加。然而，大多数 到目前为止，研究已经评估了这些感染在单个时间点或在不频繁的时间点，这提供了 关于这些感染的动态及其对疟疾的可能贡献的信息很少或根本没有 变速箱。最近的数据表明，无症状寄生虫的密度可能比 之前已知的。该项目的目标是论证每日干血斑点的可行性和质量 (DBS)取样以量化低密度无症状的寄生虫和配子体密度动力学 恶性疟原虫感染以更好地了解它们对疟疾传播的可能贡献 研究在经历中间传播的人群中此类感染的自然历史。我们会 测量在28天内成功收集每日DBS的受试者的比例，并量化 随着时间的推移收集的样本的质量。用超灵敏的定量逆转录聚合酶链式反应检测P. 恶性疟原虫18S rRNA和配子体mRNA将结合在一起，以经济高效的方式识别受感染的参与者 然后解卷每日样本，说明寄生虫密度的动态变化。如果成功，则结果来自 这项研究将为进一步研究低密度寄生虫携带和BE的动力学提供技术手段。 可推广到其他疟疾流行国家面临无症状的公共卫生问题 疟疾用于控制和消除疟疾。

ABSTRACT There are a significant number of low-density Plasmodium infections in endemic populations, and the proportion of this type of infection appears to increase with decreasing transmission intensity. However, most studies to date have assessed these infections at a single time point or at infrequent time points, which offers little to no information on the dynamics of these infections and their possible contribution to malaria transmission. Recent data suggest that asymptomatic parasite densities may be much more dynamic than previously known. The goal of this project is to demonstrate the feasibility and quality of daily dried blood spot (DBS) sampling in order to quantify parasite and gametocyte density kinetics of low-density asymptomatic Plasmodium falciparum infections to better understand their possible contribution to malaria transmission by studying the natural history of such infections in a population experiencing intermediate transmission. We will measure the proportion of subjects who successfully collect daily DBS over a 28-day period, and quantify the quality of the samples collected over time. Ultrasensitive quantitative reverse transcription PCR for P. falciparum 18S rRNA and gametocyte mRNA will be combined to cost-effectively identify infected participants and then deconvolute daily samples to illustrate the parasite density kinetics. If successful, the results from this study will offer a technique to further study the dynamics of low-density parasite carriage and be generalizable to other malaria-endemic countries confronting the public health problem of asymptomatic malaria for malaria control and elimination.