Improved Rapid Detection of Viable Waterborne Pathogens

Our successfully completed Phase I efforts demonstrated that exceedingly low numbers (five or less) of oocysts from human pathogenic strains of Cryptosporidium, including C. parvum and C. hominis can be detected in drinking water using the isothermic Nucleic Acid Sequence Based Amplification (NASBA) method combined with a rapid liposome nanovesicle-based biosensor technology. Additionally, the CryptoDetect™ Test System that has been developed can distinguish viable from nonviable oocysts and can correctly detect low number of C. parvum, even in the presence of overwhelming numbers of other contaminating waterborne pathogens. In direct head-to-head comparison against Method 1622, the CryptoDetect™ Test System yielded equivalent results. The assay system is based on the immunocapture of low numbers of oocysts, which can be heat shocked to induce the production of a specific mRNA, which in turn can be amplified by NASBA and detected in an easy-to-perform and interpret manner. The entire assay can be completed in less than 4 hours, is less complicated to perform than current methods, and can distinguish nonviable oocysts. Furthermore, the improved assay system will reduce the number of false positive determinations caused by misreading of immunofluorescence slides. The Phase II efforts will focus on transforming the above laboratory findings into a commercial product with applications in the drinking water industry. Those efforts will focus on: Finalize the detection limit of the test. Compare current viability/infectivity assays against results of the CryptoDetect™ Test System. Determine the effect of contaminants that might be found in raw water samples and whether changes need to be made to overcome any such effects. Further simplify the test methods required. Evaluate the CryptoDetect™ Test System in head-to-head comparison against Method 1622 using and independent Verification Testing Organization (VTO) approved by the U.S. Environmental Protection Agency (EPA). Finally, information contained within the “Technology Niche Assessment” completed by Foresight Technologies on behalf of EPA, will continue to be used to attract a commercial partner to manufacture and market the product to the drinking water industry.