AWWA WQTC56954

Norwalk and other Noroviruses are being increasingly recognized as major contributors to the disease burden caused by contaminated water supplies. Improved methods for the detection and quantitation of these microbes in water is essential for performing disease outbreak investigations and developing monitoring strategies for management efforts to minimize human exposures to contaminated water. Filtration-adsorption is commonly used to recover and concentrate these viruses from large volumes of water, but some research suggests that commonly-used beef extract-based filter elution solutions contain substances that inhibit reverse transcriptase-polymerase chain reaction (RT-PCR) assays for detecting these viruses. The results of this study indicate that a simple, well-defined eluent composed of L-lysine, and the detergent, Triton X-100, was an effective alternative to eluents containing beef extract. No significant differences in Norwalk Virus recovery were measured between the lysine- and beef extract-based eluents when virus RNA was heat-released from eluent concentrates of tap water experiments. When the filtration-elution method was applied to tap water seeded with approximately 103 Norwalk viruses, the lysine-based eluent was found to yield significantly greater recoveries of Norwalk viruses than 3% beef extract, 0.05M glycine (pH 9.5). Data from filtration-elution experiments with seeded surface water also indicated that the lysine-based eluent achieved similar or greater recoveries of Norwalk viruses compared to the beef extract-based eluent. The results from this study show that a high-molar lysine eluent can be an effective alternative to beef extract eluents for detecting relatively low levels of Norwalk viruses in tap water and surface water samples. Includes 10 references, tables, figures.