Environmental sampling of Leptospira species to link to human leptospirosis cases

对钩端螺旋体物种进行环境采样以与人类钩端螺旋体病病例联系起来

• 批准号: 8497278
• 负责人: Talima Ross Pearson
• 金额: $ 43.56万
• 依托单位: NORTHERN ARIZONA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-08-20 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8497278
• 关键词: Address; Affect; Animals; Bacteria; Biological Assay; Case Study; Cattle; Cessation of life; Characteristics; Cities; Clinical; Collection; Communities; Complex; Contracts; Dideoxy Chain Termination DNA Sequencing; Disease; Distant; Ecuador; Environment; Environmental Risk Factor; Epidemiology; Etiology; Exposure to; Family suidae; Fever; Frequencies; Genomics; Genotype; Headache; Human; Icterus; Incidence; Infection; Ingestion; Kidney; Kidney Failure; Leptospira; Leptospirosis; Link; Liver Failure; Livestock; Location; Mammals; Measures; Monitor; Mucous Membrane; Order Spirochaetales; Oxygen; Play; Rain; Rattus; Rivers; Role; Sampling; Site; Source; Surveys; Technology; Temperature; Testing; Time; Urine; Water; Weather; Work; human disease; insight; microbial community; next generation sequencing; pet animal; physical property; public health relevance; rRNA Genes; transmission process; water sampling; waterborne; weather patterns

DESCRIPTION (provided by applicant): Leptospirosis is a common zoonotic disease most prevalent in the tropics and developing world. Death occurs in over 10% of the ~350,000 cases reported worldwide annually. Despite this ubiquity and incidence of disease, much remains unknown about environmental cycling and transmission to humans. Pathogenic Leptospira bacteria contaminate the environment when shed by urine from mammalian hosts into the environment. Humans often contract leptospirosis from contaminated water or from direct exposure to infected urine. However, cases of leptospirosis have been documented from contact with water with little suspected leptospire contamination, suggesting that other potentially important factors affecting Leptospira persistence and transmission need to be identified. Livestock, pets and peridomestic rats as well as weather patterns are thought to play significant roles in environmental cycling and have been correlated to leptospirosis in humans, but direct epidemiological links are missing. The long-term objective of this work is to reduce the number of leptospirosis cases by better understanding links between Leptospira in the environment and leptospirosis in humans. This study will be conducted around Portoviejo City, Ecuador, where leptospirosis cases are common and will involve collection and analyses of environmental, animal and clinical samples. The central hypothesis of this proposal is that specific sources are more important than others for human transmission. Testing this hypothesis will involve addressing two specific aims. The first is to track environmental loads of pathogenic Leptospira over time and search for biotic and abiotic correlates. As leptospirosis is water borne, samples will be collected from the two large rivers near Portoviejo. Physical properties of sampling sites and samples will be obtained and the load of pathogenic Leptospira will be quantified through real- time PCR analysis. Microbial communities in each sample will be characterized by 16S rRNA gene surveys using high-throughput next-generation sequencing technology. The second specific aim will be to link environmental genotypes to clinical genotypes. Clinical samples will be collected, genotyped and compared to genotypes from samples collected from livestock, rats and river samples. These sample sources represent the most significant known sources of leptospirosis infections and thus provide a unique opportunity to link environmental and animal genotypes to human disease.

描述（由申请人提供）：钩端螺旋体病是一种常见的人畜共患病，在热带地区和发展中国家最为流行。全球每年报告的约 350,000 例病例中，超过 10% 发生死亡。尽管疾病普遍存在且发病率高，但关于环境循环和向人类传播的情况仍有很多未知之处。当致病性钩端螺旋体细菌通过哺乳动物宿主的尿​​液排入环境中时，会污染环境。人类经常因受污染的水或直接接触受感染的尿液而感染钩端螺旋体病。然而，已记录了因接触几乎没有疑似钩端螺旋体污染的水而引起的钩端螺旋体病病例，这表明需要确定影响钩端螺旋体持久性和传播的其他潜在重要因素。牲畜、宠物和家周围的老鼠以及天气模式被认为在环境循环中发挥着重要作用，并且与人类钩端螺旋体病相关，但缺乏直接的流行病学联系。这项工作的长期目标是减少 通过更好地了解环境中的钩端螺旋体与人类钩端螺旋体病之间的联系，减少钩端螺旋体病病例的数量。这项研究将在厄瓜多尔波托维耶霍市周围进行，那里钩端螺旋体病病例很常见，并将涉及环境、动物和临床样本的收集和分析。该提案的中心假设是，对于人类传播，特定来源比其他来源更重要。检验这一假设将涉及解决两个具体目标。第一个是随着时间的推移跟踪致病性钩端螺旋体的环境负荷并寻找生物和非生物相关性。由于钩端螺旋体病是水传播的， 样本将从波托维耶霍附近的两条大河中采集。将获得采样点和样品的物理特性，并通过实时 PCR 分析定量致病性钩端螺旋体的负荷。每个样本中的微生物群落将通过使用高通量下一代测序技术的 16S rRNA 基因调查来表征。第二个具体目标是将环境基因型与临床基因型联系起来。将收集临床样本，进行基因分型，并与从牲畜、大鼠和河流样本中收集的样本的基因型进行比较。这些样本来源代表了已知的最重要的钩端螺旋体病感染来源，因此提供了将环境和动物基因型与人类疾病联系起来的独特机会。

项目成果

Critical Knowledge Gaps in Our Understanding of Environmental Cycling and Transmission of Leptospira spp.

我们对环境循环和钩端螺旋体传播的理解存在关键知识差距。

• 发表时间: 2017-10-01
• 影响因子: 4.4
• 作者: Barragan, Veronica;Olivas, Sonora;Keim, Paul;Pearson, Talima
• 通讯作者: Pearson, Talima

Meta-analysis to estimate the load of Leptospira excreted in urine: beyond rats as important sources of transmission in low-income rural communities.

估计尿液中钩端螺旋体排泄量的荟萃分析：除了老鼠之外，它也是低收入农村社区的重要传播来源。

• 发表时间: 2017-01-28
• 影响因子: 1.8
• 作者: Barragan, Veronica;Nieto, Nathan;Keim, Paul;Pearson, Talima
• 通讯作者: Pearson, Talima

Draft Genome Sequence of the First Pathogenic Leptospira Isolates from Ecuador.

厄瓜多尔第一个致病性钩端螺旋体分离株的基因组序列草案。

• 发表时间: 2016-05-05
• 作者: Barragan, Veronica;Sahl, Jason W;Wiggins, Kristin;Chiriboga, Jorge;Salinas, Ana;Cantos, Nancy E;Loor, Mariana N;Intriago, Bertha I;Morales, Melba;Trueba, Gabriel;Pearson, Talima
• 通讯作者: Pearson, Talima

High Leptospira Diversity in Animals and Humans Complicates the Search for Common Reservoirs of Human Disease in Rural Ecuador.

动物和人类中钩端螺旋体的高度多样性使厄瓜多尔农村地区寻找人类疾病常见宿主的工作变得更加复杂。

• 发表时间: 2016-09
• 影响因子: 3.8
• 作者: Barragan, Veronica;Chiriboga, Jorge;Miller, Erin;Olivas, Sonora;Birdsell, Dawn;Hepp, Crystal;Hornstra, Heidie;Schupp, James M;Morales, Melba;Gonzalez, Manuel;Reyes, Soraya;de la Cruz, Carmen;Keim, Paul;Hartskeerl, Rudy;Trueba, Gabriel;Pears
• 通讯作者: Pears