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Norovirus genogroup I (GI) and GII in wastewater at different locations in France are quantified by using real-time reverse transcription-PCR (rRT-PCR). The results have shown that GI and GII are seen at high concentrations in the influents at all four sites during the winter gastroenteritis community outbreaks and that each of the treatment systems have reduced viral concentrations.

The article focuses on the plan of the local government of California to seek for an alternative water sources to address the scarcity of drinking water supply in the state. Topics discussed include the increase use of wastewater effluent and water conservation measures, rainwater harvesting, and examination of alternative water source for potable use.

The article offers information on water reuse technologies and details key factors to be considered in implementing water recycling in various categories including industrial, urban, and agricultural. Topics discussed include water recycling in various industries including high-technology manufacturing, prepared food manufacturing, and natural gas and oil production. Guidelines on wastewater reuse feasibility is also presented.

The transport properties (adsorption and aggregation behavior) of virus-like particles (VLPs) of two strains of norovirus ("Norwalk" GI.1 and "Houston" GII.4) were studied in a variety of solution chemistries. GI.1 and GII.4 VLPs were found to be stable against aggregation at pH 4.0-8.0. At pH 9.0, GI.1 VLPs rapidly disintegrated. The attachment efficiencies (a) of GI.1 and GII.4 VLPs to silica Increased with increasing Ionic strength in NaCI solutions at pH 8.0. The attachment efficiency of GI.1 VLPs decreased as pH was increased above the isoelectric point (pH 5.0), whereas at and below the isoelectric point the attachment efficiency was erratic. Ca2+ and Mg2+ dramatically increased the attachment efficiencies of GI.1 and GII.4 VLPs, which may be due to specific interactions with the VLP capsids. Bicarbonate decreased attachment efficiencies for both GI.1 and GII.4 VLPs, whereas phosphate decreased the attachment efficiency of GI.1, while increasing GII.4 attachment efficiency. The observed differences in GI.1 and GII.4 VLP attachment efficiencies in response to solution chemistry may be attributed to differential responses of the unique arrangement of exposed amino acid residues on the capsid surface of each VLP strain. [ABSTRACT FROM AUTHOR]

The presence of norovirus (NoV) genogroup I (GI) and II (GII) was evaluated using real-time reverse transcription polymerase chain reaction (rRT-PCR) in the influent, two midtreatment locations, and final effluent of a three-pond serial waste stabilization pond system from December 2005 through June 2006. Additionally, influent and effluent samples were filtered through a cascade of three membrane filters with sequentially smaller pores to determine the size range of particles with which GI and GII were associated. NoV GI and GII removal occurs primarily in the third pond. Viruses were found on large settleable particles (retained on a 180 μm filter), on smaller suspended particles (retained on a 0.45 μm filter), on colloidal particles (retained on a positively charged 0.45 am filter), and in the final filtrate. Both GI and GII in influent samples were found to be dominantly associated with particles smaller than 180 μm, thereby suggesting that particle settling is not the main virus removal mechanism in the waste stabilization pond system. On average, NoV detected in filtered effluent samples were associated with particles between 0.45 and 180 μm in diameter (47 and 67% of detected GI and GII, respectively). The presence of NoV GI and GIl in the final filtrate of influent and effluent samples shows that positively charged membrane filters often used for viral concentration methods are not capable of trapping all viruses present in wastewater samples. [ABSTRACT FROM AUTHOR]

Needless to say, the safety of treated water for potable reuse must be definitively ensured. Numerous methods are available for assessing water quality; it's important to understand their challenges and limitations., (© 2019 American Water Works Association.)