Development of a Simple Diagnostic for Causative Agents of Schistosomiasis

点击翻译按钮获取中文摘要

PROJECT SUMMARY Schistosomiasis is a neglected tropical disease (NTD) caused by parasitic worms and is second only to malaria as the most devastating parasitic disease. It is currently estimated that more than 200 million people are infected and 700 million more are considered at risk. Humans become infected when doing activities in freshwater (e.g., Schistosoma-contaminated lakes, rivers) such as washing cars and fishing. The highest incidence of schistosomiasis is in children and young adolescents with persistence of disease in adults who have frequent contact with water. Current approaches for the diagnosis of schistosomiasis require high infection levels for successful detection or are unable to determine if a positive diagnosis represents a past or current infection. Nucleic acid-based techniques to detect schistosome DNA have substantially greater sensitivity than the existing microscopy- or antigen-based methods, higher specificity and can diagnose ongoing infections. Lynntech proposes to develop a user-friendly, low-cost, portable PCR-based human diagnostic (called NTDx-S) to detect causative organisms in human samples in low resource settings. The NTDx-S system will be based on PCR- mediated amplification of specific genes, and a lateral flow (LF)-based detection method to produce a specific diagnostic signal. During this effort, Lynntech will expand upon a previously developed schistosomiasis PCR-LF detection assay and develop PCR reactions aimed at the amplification of species specific loci. To ensure the detection of all potential causes of disease, we will also develop a primer set capable of detecting a pan locus, enabling detection of each schistosome species, including hybrids. Two separate LF strips will be developed that detect the pan locus alongside species specific loci from the three main species responsible for disease. These two strips will be designed to detect schistosomes based on their geographical distribution. Finally, we will develop a simple, low power sample preparation protocol, aimed at isolating schistosome eggs from human urine/stool samples. These samples may be processed in the NTDx-S system as the end user requires based on region of use. Schistosomiasis endemic countries require diagnostics which are economical and simple to operate. Therefore, during the development of the NTDx-S diagnostic, efforts will be focused at each step to limit power requirements and achieve a cost-friendly, simple assay. The development of Lynntech's NTDx-S system will enable non-specialized operators in non-traditional settings to perform sophisticated biological testing.