Leptospira prevalence, cycling, and infection in the peridomestic environment

家庭周围环境中钩端螺旋体的流行、循环和感染

基本信息

批准号：
10735030
负责人：
Talima Ross Pearson
金额：
$ 71.3万
依托单位：
NORTHERN ARIZONA UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-01 至 2028-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10735030
关键词：
Address Animal Sources Animals Area Bacteria Biological Biological Assay Case Study Cessation of life Clinical Communities Complex Contracts Death Rate Disease Disease Outbreaks Domestic Animals Ecology Ecuador Environment Epidemiology Exclusion Exposure to Family Fever Future Genetic Variation Genotype Hawaii Headache Home Human Icterus Individual Infection Infection Control Infection prevention Ingestion Interview Investigation Kidney Failure Knowledge Leptospira Leptospirosis Link Liver Failure Livestock Location Low income Methods Modernization Molecular Mucous Membrane Outcome Pathogenicity Patients Pattern Persons Play Population Dynamics Prevalence Prevention strategy Resolution Risk Risk Factors Role Rural Rural Community Sampling Seasonal Variations Seasons Site Slum Soil Source Symptoms Time Urine Variant Water Zoonoses disorder control disorder prevention experience exposed human population follow-up genome sequencing insight novel pathogen recruit rural area rural environment tool transmission process urban area urban setting whole genome wound

项目摘要

Project Summary Leptospirosis is a common zoonotic disease most prevalent in the tropics (Hawaii, US territories, and worldwide). Non-specific symptoms cause underreporting and of the 1.03 million reported cases annual worldwide, ~6% die. Infectious Leptospira bacteria contaminate the environment when shed in urine from mammalian hosts, and humans can contract leptospirosis directly from infected urine or from contaminated soil and water. While case interviews have identified risk factors for human infections and potential reservoirs, the few molecular and microbiological investigations of human cases almost always failed to confirm hypothesized sources, suggesting that exposure and possible sources have not been adequately defined and environmental cycling across hosts, space, and time is poorly understood. The complex ecology of this disease involves various host species, survival in the environment, massive pathogen genetic diversity, and seasonal variation in human cases, all of which are poorly characterized and poorly understood. Difficulties in culturing Leptospira have restricted the use of modern molecular tools that, for other pathogens, have been critical for understanding cycling and confirming or refuting source hypotheses generated using traditional epidemiological approaches. However, we recently developed a culture-free method for high-resolution genotyping of Leptospira, enabling us to characterize cycling patterns across hosts, space, and time, and provide high-quality evidence linking infections to specific sources. For this study, we focus on peridomestic environments (where animals live near human habitations) because they are likely an important, underestimated, and poorly understood source for human infections in rural areas. Our field site is in Calderon Parish in Manabí, where leptospirosis cases are most prevalent in Ecuador. Compared to urban areas where leptospirosis is typically studied, low-income rural areas are fundamentally different: families typically own a variety of animals and livestock that roam in and around homes creating exposure potential that is largely absent from urban environments. We will systematically sample peridomestic environments (humans, other animals, and soil) to characterize variation in prevalence, pathogen load, and genotype across hosts, time, and space. We will also recruit leptospirosis patients to perform microbiological and molecular investigations of their peridomestic environment to determine what, if any, peridomestic reservoirs are likely sources for these human infections. This study will provide novel insights into the prevalence and cycling of this pathogen in hosts and soil in the peridomestic environment and each investigation will generate novel and powerful molecular and microbiological evidence to exclude or confirm the peridomestic environment as the source of each human infection. Comparisons across these investigations will provide insights into how widespread such sources are in this region of Ecuador and will form the basis for future investigations to determine the generalizability of these patterns. Results will fill massive knowledge gaps critical for transmission control and disease prevention.

项目概要钩端螺旋体病是一种常见的人畜共患病，在热带地区（夏威夷、美国领土和全世界）最为流行。非特异性症状导致漏报，全球每年报告的 103 万例病例中，约有 6% 死亡。当传染性钩端螺旋体细菌从哺乳动物宿主的尿液中排出时，会污染环境，并且人类可以直接从受感染的尿液或受污染的土壤和水中感染钩端螺旋体病。访谈已经确定了人类感染的危险因素和潜在的储存者，少数分子和对人类病例的微生物学调查几乎总是无法确认来源，这表明暴露和可能的来源尚未得到充分定义以及宿主之间的环境循环，人们对这种疾病的复杂生态学涉及多种宿主物种、生存状况知之甚少。在环境中，大量的病原体遗传多样性以及人类病例的季节性变化，所有这些都是钩端螺旋体培养方面的困难限制了现代技术的使用。对于其他病原体来说，分子工具对于理解循环以及确认或反驳至关重要使用传统流行病学方法产生的来源假设然而，我们最近开发了一个。用于钩端螺旋体高分辨率基因分型的免培养方法，使我们能够表征循环模式跨宿主、空间和时间，并提供将感染与特定来源联系起来的高质量证据。在这项研究中，我们重点关注家庭周围环境（动物生活在人类居住地附近），因为它们可能是农村地区人类感染的一个重要的、被低估的和知之甚少的来源。我们的现场地点位于马纳比的卡尔德隆教区，那里是厄瓜多尔钩端螺旋体病病例最流行的地方。与通常研究钩端螺旋体病的城市地区相比，低收入农村地区从根本上来说是不同：家庭通常拥有各种动物和牲畜，它们在房屋内和周围漫步，创造了我们将系统地对家庭周围环境进行采样。环境（人类、其他动物和土壤）来表征患病率、病原体负荷和我们还将招募钩端螺旋体病患者进行微生物学检查。对它们的周围环境进行分子研究，以确定哪些（如果有）周围的水库可能是这些人类感染的来源。这项研究将为该病原体在宿主和土壤中的流行和循环提供新的见解。家庭周围环境和每次调查都会产生新颖而强大的分子和微生物学排除或确认家庭周围环境是每次人类感染源的证据。对这些调查进行比较将有助于了解此类来源在这一领域的广泛程度。厄瓜多尔地区，并将成为未来调查的基础，以确定这些问题的普遍性结果将填补对传播控制和疾病预防至关重要的巨大知识空白。

项目成果

期刊论文数量（2）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Domestic dogs in indigenous Amazonian communities: key players in Leptospira cycling and transmission?

亚马逊土著社区的家犬：钩端螺旋体循环和传播的关键参与者？

DOI：
发表时间：
2023-09-20
期刊：
影响因子：
0
作者：
Guzmán, Diego A;Diaz, Eduardo;Sáenz, Carolina;Álvarez, Hernán;Cueva, Rubén;Zapata;Prado;Falconí, Mercy;Pearson, Talima;Barragán, Verónica
通讯作者：
Barragán, Verónica

Domestic dogs in indigenous Amazonian communities: Key players in Leptospira cycling and transmission?

亚马逊土著社区的家犬：钩端螺旋体循环和传播的关键角色？

DOI：
发表时间：
2023-09-20
期刊：
影响因子：
3.8
作者：
Guzmán DA;Diaz E;Sáenz C;Álvarez H;Cueva R;Zapata-Ríos G;Prado-Vivar B;Falconí M;Pearson T;Barragán V
通讯作者：
Barragán V