Surface waters provide a challenge for pathogen detection due to changing environmental conditions and microbial populations that may affect method chemistry. Due to the importance of these pathogens with regard to human health, rapid detection and screening of water samples is necessary to determine the risks of potential pathogens present at any given time. The ANSR assay, using Nicking Enzyme Amplification Reaction (NEARTM) technology, originally developed for food safety, was tested for its effectiveness in detecting Salmonella in surface waters. The main objective of this study was to determine if the ANSR assay is appropriate for detection of Salmonella in surface waters and comparable to the current culture-based industry standard USEPA 1682 method. These methods were tested by comparing their ability to detect seeded and naturally-occurring Salmonella in surface waters from around Michigan and northern Ohio. The ANSR assay and the USEPA 1682 method found 84.4% and 31.4% of samples positive for naturally-occurring Salmonella, respectively. The ANSR assay has shown the ability to detect Salmonella in surface waters at least as well as the USEPA 1682 method, but because of its much higher potential for false positives and its low precision and accuracy rates, it should be used in conjunction with other detection methods to confirm positive results. This assay shows potential for use as a rapid screening tool for surface water samples in order to prioritize in depth testing at sites, however what appears to be false-positives will need to be reduced.
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