Asymptomatic Gametocytemia and Malaria: Implications for Plasmodium Transmission

无症状配子体增多症和疟疾：对疟原虫传播的影响

• 批准号: 8700813
• 负责人: MARK L WILSON
• 金额: $ 25.48万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-03-06 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8700813
• 关键词: Address; Adult; Affect; Age; Anopheles Genus; Antimalarials; Area; Behavioral; Biological Assay; Blood; Blood specimen; Breeding; Characteristics; Clinical; Communities; Culicidae; Detection; Disease; Ecology; Enzyme-Linked Immunosorbent Assay; Evaluation; Event; Female; Funding; Future; Health; Household; Human; Immunity; Incidence; Individual; Infection; Intervention; Investigation; Laboratories; Lead; Life; Link; Location; Malaria; Malaria prevention; Malawi; Methods; Microscopic; Microscopy; Midgut; Molecular; Molecular Diagnostic Techniques; Molecular Genetics; Parasitemia; Parasites; Pattern; Pharmaceutical Preparations; Plasmodium; Plasmodium falciparum; Population; Prevalence; Prevention; Questionnaires; Recording of previous events; Research; Research Project Grants; Risk; Risk Factors; Role; Salivary Glands; Sampling; Seasons; Site; Staging; Symptoms; Techniques; Testing; Time; United States National Institutes of Health; Work; density; design; feeding; innovation; insight; international center; land cover; novel; pathogen; prevent; public health relevance; research study; residence; transmission process; vector; vector mosquito

DESCRIPTION (provided by applicant): One challenge to understanding and preventing malaria is that people who are infected with Plasmodium parasites, and potentially infectious to mosquito vectors, are frequently asymptomatic, hence not recognized as contributing to transmission dynamics. This research project will determine which people are infected with Plasmodium gametocytes, evaluate resulting mosquito infections that derive from those infectious people, and infer population-level patterns of malaria risk that emerge from these transmission events. We will take advantage of ongoing NIH-funded research (International Centers of Excellence for Malaria Research) in southern Malawi where different intensities of transmission occur. Using a new molecular-genetic detection technique (qRT-PCR) for recognizing low-density P. falciparum gametocytes that are not normally seen through microscopy, we will explore associations between infection and symptoms, treatment, age and various environmental/behavioral risk factors. Specifically, we will test three hypotheses addressing 1) the prevalence of parasitemia, and specifically gametocytemia, in relation to transmission intensity and treatment, 2) patterns of gametocytemia with regard to age, mosquito ecology, and anti-malarial interventions, and 3) impacts on household-level transmission to Anopheles vectors. This project is innovative in using a new molecular diagnostic method to evaluate naturally-infected, asymptomatic people combined with non-experimental field transmission to mosquitoes found in common living contexts of the region. We expect our results to have household- and community-level transmission implications for treatment and prevention that may affect the seasonality and annual re-intensification of transmission in ways that are dynamically counterintuitive.

描述（由申请人提供）：理解和预防疟疾的一个挑战是，感染了疟原虫寄生虫并可能对蚊子向量感染的人通常是无症状的，因此不被认为有助于传播动态。该研究项目将确定哪些人感染了疟原虫，并评估源自这些传染性人的蚊子感染，并推断出从这些传播事件中出现的疟疾风险的种群水平模式。我们将利用在马拉维南部进行的持续的NIH资助研究（国际疟疾卓越研究中心），那里发生了不同的传播强度。使用新的分子基因检测技术（QRT-PCR）识别通常不会通过显微镜观察到的低密度恶性疟原虫配子细胞，我们将探索感染与症状，治疗，年龄，各种环境/行为/行为/行为风险因素之间的关联。具体而言，我们将检验三个解决方案的假设1）与传播强度和治疗有关的寄生虫的普遍性，特别是配子细胞血症，2）关于年龄，蚊子生态学和抗马利亚干预措施以及3）影响的配子细胞血症模式关于家庭级传输到肛门载体。该项目使用一种新的分子诊断方法来评估自然感染的，无症状的人与非实验性现场传播到该地区常见生活环境中发现的蚊子。我们希望我们的结果对治疗和预防的家庭和社区水平传播的影响可能会影响季节性和年度重新巩固传播的传播方式，以动态违反直觉。