Newton001 Sero-surveillance to estimate the burden of Plasmodium vivax and P. falciparum infection in Latin America

消除疟疾需要在治疗疟疾患者之外，将活动重点放在减少社区内寄生虫的传播上。然而，随着疟疾传播水平的下降，使用常规方法（显微镜、快速诊断测试）识别可能携带寄生虫的个体变得更加困难，因为这些感染中的许多感染将是低密度和无症状的。因此，需要采用创新和负担得起的方法来确定可能的寄生虫携带者及其居住的地区。一种方法是血清学监测。疟疾感染将在人类宿主的血清中留下抗体“足迹”，其持续时间长于感染本身。检测这些抗体是测量人群感染暴露水平的另一种敏感和特异性方法。LSHTM的研究人员最近重新利用这种方法使用抗体，作为一种相当准确地估计疟疾负担的方法。抗体测量已被证明与疟疾负担（昆虫学、寄生虫学和临床）的其他常规估计相关。研究还表明，通过评估抗体反应和个体年龄，有可能重现疟疾暴露史。这方面允许对某一地区疟疾控制干预措施的效果进行回顾性检查。这项工作主要是在恶性疟原虫占主导地位的非洲环境中进行的，但最近对巴西帕拉州的样本进行的分析表明，该方法适用于这种环境。因此，该项目的目的是通过收集拉丁美洲血清流行病学和抗体动态的现有证据，并通过新的抗体靶点和分析方法来扩展这项工作。该项目的预期结果是促进更好地了解拉丁美洲血清监测证据的现状，并确定在未来研究中需要解决的研究问题。制定这些研究报告是为了进一步加强参与机构之间的合作，制定可靠的血清监测方法，以估计该区域特定物种的疟疾负担，制定目标控制方法，并最终促进该区域消除疟疾。这项建议具体解决了对快速和可靠的工具和战略的需求，以衡量疟疾负担，我们认为它将为指导拉丁美洲的决策者提供大量信息。

Malaria elimination requires that activities focus on reducing parasite carriage within communities in addition to treating those sick with the disease. However, as malaria transmission levels decrease, it becomes harder to identify individuals who might be carrying parasites using conventional methods (microscopy, rapid diagnostic tests), as many of these infections will be of low density and asymptomatic. Therefore, there is a need for innovative and affordable approaches to identify likely parasite carriers and the areas where they reside. One approach is serological surveillance. A malaria infection will leave an antibody 'footprint' in the serum of the human host that will last longer than the infection itself. Detection of these antibodies is an additional sensitive and specific approach to measure a population's level of exposure to infection. Using antibodies in this way has recently been revitalised by researchers at LSHTM as a method to estimate malaria burden with considerable accuracy.Antibody measures have been shown to correlate with other conventional estimates of malaria burden (entomological, parasitological and clinical). It has also been shown that by evaluating the antibody responses and age of individuals it is possible to recreate the history of exposure to malaria. This facet allows a retrospective examination of the effect of malaria control interventions in a given locality. This work has primarily been conducted in African settings where Plasmodium falciparum is predominant, however a more recent analysis of samples from Para state, Brazil showed the approach was applicable in this setting. Therefore, the aim of this project is to extend this work by assembling the current evidence on sero-epidemiology and antibody dynamics in Latin America and extending this with novel antibody targets and analytical approaches.The expected results of this project are to promote better understanding of the current landscape of sero-surveillance evidence in Latin America and to identify research needs to be addressed in future studies. These studies will be formulated to further strengthen collaboration between participating institutions in developing reliable sero-surveillance methods to estimate species-specific malaria burden in the region, target control methods and ultimately contribute to malaria elimination in the region. This proposal specifically addresses the need for rapid and reliable tools and strategies to measure malaria burden and we believe it will provide considerable information to guide policy makers in Latin America.