Defining cutoffs for the Point-of-Care Circulating Cathodic Antigen (POC CCA) assay in areas of low Schistosoma mansoni prevalence in western Kenya

项目摘要 目前，监测和评估曼氏血吸虫控制方案 通过使用加藤-卡茨技术检测粪便样本中的寄生虫卵来执行。 这种方法在灵敏度方面有已知的局限性，需要训练有素的显微镜专家和 进行评估的功能显微镜。最近(2008年)，一个关注点 (POC)检测尿中曼氏沙门氏菌循环阴极抗原(CCA) 成为商业上可用的。它更便宜，更易于部署，具有比 大便检查，治疗成功后迅速转为阴性。在世界卫生组织 2015年2月举行的血吸虫病诊断会议，工作组和 随后，战略和技术咨询小组(STAG)鼓励增加 验证POC-CCA以更好地定义计划应使用的截止日期 曼氏血吸虫防治的决策以及监测和评估 程序。需要更多关于新开发的血吸虫性能的数据 在流行和丙二醛后环境中进行抗原测试，以便能够开发 关于以编程方式使用这些工具的建议。现有证据表明 在高流行地区(≥50%)，加藤-卡茨和POC-CCA检测都提供了 合理和可比的流行率水平，目前的指导方针是 完全足以控制发病率。然而，可供比较的数据很少。 在发病率较低(30%)的地区。因此，我们在这项研究中建议评估 POC、CCA和Kato-Katz检测在低S区的诊断性能 曼苏尼在肯尼亚西部的流行情况。这项研究的发现将有助于澄清 Kato-Katz与POC-CCA的关系及视觉POC-CCA的判定 CCA频段强度可以用来评估治疗效果，以告知 计划干预。

Project Abstract Monitoring and evaluation of control programs for Schistosoma mansoni is currently performed by detection of parasite eggs in stool samples using the Kato-Katz technique. This method has known limitations in sensitivity and requires trained microscopists and functional microscopes to perform the assessments. Recently (in 2008), a point of care (POC) test that detects S. mansoni circulating cathodic antigen (CCA) in urine has become commercially available. It is cheaper, easy to deploy, has greater sensitivity than stool exam and rapidly becomes negative upon successful treatment. At the WHO meeting on schistosome diagnostics in February 2015, the working group and subsequently the Strategic and Technical Advisory Group (STAG) encouraged additional validation of the POC-CCA to better define what cutoffs should be used for program decision making as well as for monitoring and evaluation for S. mansoni control programs. More data are needed on the performance of newly developed schistosomal antigen tests in endemic and post-MDA settings in order to be able to develop recommendations for programmatic use of these tools. Existing evidence suggests that in areas of high prevalence (≥ 50%), the Kato-Katz and POC-CCA assays both provide reasonable and comparable levels of prevalence and that the current guidelines are entirely adequate for morbidity control. However, there is a paucity of comparable data in areas of low (< 30%) prevalence. Thus, we propose in this study to evaluate the diagnostic performance of the POC CCA and Kato-Katz assays in areas of low S. mansoni prevalence in western Kenya. Findings from this study will help to clarify the relationship between Kato-Katz and POC-CCA and determine whether the visual POC- CCA band intensities can be used to evaluate treatment efficacy in order to inform program interventions.