Assessing Virus Concentration Methods for Norovirus and SARS-CoV-2 Detection in Wastewater

Polyethylene Glycol (PEG) precipitation and Nanotrap® Microbiome Particles (NMP) are widely used methods for concentrating viruses in wastewater due to their simplicity, cost-effectiveness, efficiency, and rapid turnaround time. This study compared the performance of these methods in detecting noroviruses (GI and GII) and SARS-CoV-2 collected from two wastewater treatment facilities using quantitative PCR. Norovirus was detected in all samples (23/23) using both protocols, but PEG yielded higher mean concentrations for GI and GII than NMP, indicating improved quantitative recovery for non-enveloped viruses. For SARS-CoV-2, NMP showed significantly higher positive ratios for the N2 gene (Fisher’s Exact Test, p < 0.01), but no significant difference was observed for the N1 gene (p > 0.05), indicating comparable performance between the methods for this target. These findings highlight PEG’s effectiveness for non-enveloped viruses and NMP’s suitability for enveloped viruses, emphasizing the importance of selecting virus concentration methods based on viral structure. This study provides a framework for optimizing wastewater-based epidemiology (WBE) protocols and enhancing public health surveillance for diverse viral targets. Future research should focus on refining these methodologies and exploring their applicability to other viral pathogens to enhance public health surveillance frameworks.