Human enteric viruses are currently listed on the United States Environmental Protection Agency Contaminant Candidate List (USEPA CCL) as emerging contaminants and have been linked to several waterborne diseases, such as acute gastroenteritis, conjunctivitis and respiratory illness. In this study, a total of 82 wastewater samples using two different electropositive filters and 6 biosolids samples were analyzed from five separate full-scale wastewater treatment plants (WWTPs) in Michigan using real-time PCR and cell culture assays. Adenovirus (HAdV), enterovirus (EV) and norovirus genogroup II (NV2) were detected in approximately 100%, 84% and 37%, respectively of all wastewater samples using real-time PCR. Cytopathic effect (CPE) was present in 100% of the cell culture samples for influent, pre and post disinfection and biosolids with an average concentration of 2.2×104, 5.9×101, 6.2×100 and 2.9×107 MPN/100L, respectively. Based on real-time PCR data, we concluded a MBR system is able to achieve approximately 2 log higher reduction of HAdV (average 4.1 log units) as compared with conventional wastewater treatment (average 2.2 log units). However, similar EV log removal values (3.6 for MBR and 2.9 for conventional) were observed between the two types of treatment processes. In addition, there is a significant log reduction (2.3 - 4.5) in infectious viruses throughout the wastewater treatment process before being discharged into natural waterways.
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