Targeted screening for Taenia solium tapeworms

猪带绦虫的靶向筛查

• 批准号: 8129451
• 负责人: Seth E O'Neal
• 金额: $ 12.41万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8129451
• 关键词: Adult; Advisory Committees; Africa South of the Sahara; Age; Algorithms; Animal Husbandry; Annelida; Area; Asia; Brain; Central Nervous System Parasitic Infections; Cestoda; Cestode Infections; China; Clinical; Communities; Consumption; Control Groups; Cyst; Cysticercosis; Data; Decision Making; Detection; Development; Disadvantaged; Disease; Economics; Education; Effectiveness; Enzyme-Linked Immunosorbent Assay; Epilepsy; Family suidae; Feasibility Studies; Feces; Food Safety; Goals; Grant; Household; Human; Human Identifications; Infection; Infection prevention; International; Intervention; Investigation; Larva; Latin America; Lesion; Longevity; Low Prevalence; Marketing; Measures; Meat; Mentorship; Methods; Neurocysticercosis; Peru; Physicians; Prevalence; Public Health; Recording of previous events; Relative (related person); Research; Research Infrastructure; Research Training; Resources; Rural; Screening Result; Screening procedure; Seizures; Seroprevalences; Sewage; Source; Taenia solium; Technology; Tongue; Training; Vaccines; base; cohort; cost; design; effective therapy; egg; experience; group intervention; health economics; human migration; nervous system disorder; oxfendazole; performance tests; population based; programs; public health relevance; reproductive; socioeconomics; tool; transmission process; two-arm study

DESCRIPTION (provided by applicant): Neurocysticercosis (NCC) is the most common parasitic infection of the central nervous system, and the leading cause of acquired epilepsy in the developing world. It occurs when someone ingests Taenia solium eggs passed in the feces of a pork tapeworm carrier. The eggs grow into larvae which then form cysts throughout the body; cysts in the brain are responsible for 30% of seizures in the developing world. In Latin America, over 400,000 people of all ages and socioeconomic classes have symptomatic NCC. Sustainability of control efforts is limited by migration of human tapeworm carriers, persistent conditions for transmission and the enormous reproductive capacity of tapeworms. Our long-term goals are two-fold; 1) to develop an effective, affordable and sustainable strategy for T. solium control in endemic areas, and 2) to increase population-based research capacity around neurologic disorders in rural regions of Peru. In this R21 grant, we begin with a feasibility study of targeted screening as a control strategy, and by leveraging the resources of an existing consortium to extend research and MPH training, field experience, and mentorship to two physicians in Puno, Peru. Field data show spatial clustering of infected pigs around tapeworm carriers. With the short lifespan of pigs raised for consumption, this suggests that infected pigs may mark the presence of a nearby tapeworm carrier. Our specific aims include: 1) To implement and assess targeted screening for human T. solium tapeworm carriers in household clusters surrounding infected pigs, and 2) To identify the most effective screening tools for tapeworm carriers in the context of targeted screening. We propose an intervention cohort with two study arms. Communities in the intervention group receive ongoing targeted screening for tapeworm carriers in household clusters around infected pigs, using all available screening tools (history of passing worm segments, O&P, coproantigen ELISA, EITB, and PCR). Communities in the control group receive education about the T. solium lifecycle and how to prevent infection. We conduct pig serosurveys in both groups every 5 months, using pig seroprevalence to measure overall transmission, and provide mass tapeworm screening and treatment at study end. Our primary hypothesis is that ongoing targeted screening and treatment of tapeworm carriers will decrease transmission of T. solium infection in an endemic area, measured by serial pig seroprevalence. Our secondary hypothesis is that targeted screening around pigs with cysticercosis will increase detection of T. solium tapeworms compared to generalized screening in endemic areas. We estimate prevalence of infection among household clusters using latent-class analysis of all screening results. Finally, we use decision-making analysis to determine the most effective screening tool for targeted screening, taking into consideration test performance, cost, and relative accessibility. Our results will guide design of a subsequent large-scale T. solium control intervention using the most promising methods identified in this study. PUBLIC HEALTH RELEVANCE: Cysticercosis is an emerging public health problem in much of the developing world, where it is the leading cause of preventable epilepsy. This proposal examines targeted screening for pork tapeworm carriers as a potentially effective, affordable and sustainable control strategy.

描述（由申请人提供）：脑囊虫病（NCC）是中枢神经系统最常见的寄生虫感染，也是发展中国家获得性癫痫的主要原因。它发生在当有人摄入带绦虫卵通过粪便的猪肉绦虫载体。卵长成幼虫，然后在全身形成囊肿;大脑中的囊肿是发展中国家30%癫痫发作的原因。在拉丁美洲，所有年龄和社会经济阶层的40多万人患有症状性NCC。控制工作的可持续性受到人类绦虫携带者迁移、持续的传播条件和绦虫巨大繁殖能力的限制。我们的长期目标有两个方面：1）为T制定有效、负担得起且可持续的战略。在流行地区控制疟疾; 2）在秘鲁农村地区提高以人口为基础的神经系统疾病研究能力。在这个R21赠款，我们开始与有针对性的筛选作为控制策略的可行性研究，并通过利用现有财团的资源，以扩大研究和MPH培训，实地经验，并指导两名医生在普诺，秘鲁。现场数据显示感染的猪在绦虫携带者周围的空间聚集。由于供食用的猪的寿命很短，这表明受感染的猪可能标志着附近绦虫携带者的存在。本研究的具体目标包括：1）实施和评估人T细胞的靶向筛查;在感染猪周围的家庭集群中的猪绦虫携带者，和2）在靶向筛选的背景下确定绦虫携带者的最有效筛选工具。我们提出了一个干预队列，有两个研究组。在干预组的社区接受持续的有针对性的筛选绦虫感染猪周围的家庭集群，使用所有可用的筛选工具（通过蠕虫节段的历史，O&P，粪抗原ELISA，EITB和PCR）。对照组的社区接受有关T。solium生命周期以及如何预防感染。我们每5个月在两组中进行猪血清学调查，使用猪血清阳性率来衡量总体传播，并在研究结束时提供大规模绦虫筛查和治疗。我们的主要假设是，对绦虫携带者进行有针对性的筛查和治疗将减少绦虫的传播。流行区的猪感染，通过连续猪血清阳性率测定。我们的第二个假设是，在猪囊虫病周围进行靶向筛查将增加T。与流行地区的普遍筛查相比，我们估计感染流行的家庭集群使用所有筛查结果的潜在类分析。最后，我们使用决策分析，以确定最有效的筛选工具，有针对性的筛选，考虑到测试性能，成本和相对可及性。本文的研究结果将为后续大规模T.使用本研究中确定的最有前途的方法进行控制干预。 公共卫生相关性：囊虫病是一个新兴的公共卫生问题，在许多发展中国家，它是可预防的癫痫的主要原因。该提案审查了对猪肉绦虫携带者进行有针对性的筛查，作为一种潜在的有效，负担得起和可持续的控制策略。