title: Concentration of norovirus during wastewater treatment and its impact on oyster contamination.
abstract: The concentrations of Escherichia coli, F-specific RNA bacteriophage (FRNA bacteriophage), and norovirus genogroup I (NoV GI) and norovirus genogroup II (NoV GII) in wastewater were monitored weekly over a 1-year period at a wastewater treatment plant (WWTP) providing secondary wastewater treatment. A total of 49 samples of influent wastewater and wastewater that had been treated by primary and secondary wastewater treatment processes (primary and secondary treated wastewater) were analyzed. Using a real-time reverse transcription-quantitative PCR (RT-qPCR), the mean NoV GI and NoV GII concentrations detected in effluent wastewater were 2.53 and 2.63 log(10) virus genome copies 100 ml(-1), respectively. The mean NoV concentrations in wastewater during the winter period (January to March) (n = 12) were 0.82 (NoV GI) and 1.41 (NoV GII) log units greater than the mean concentrations for the rest of the year (n = 37). The mean reductions of NoV GI and GII during treatment were 0.80 and 0.92 log units, respectively, with no significant difference detected in the extent of NoV reductions due to season. No seasonal trend was detected in the concentrations of E. coli or FRNA bacteriophage in wastewater influent and showed mean reductions of 1.49 and 2.13 log units, respectively. Mean concentrations of 3.56 and 3.72 log(10) virus genome copies 100 ml(-1) for NoV GI and GII, respectively, were detected in oysters sampled adjacent to the WWTP discharge. A strong seasonal trend was observed, and the concentrations of NoV GI and GII detected in oysters were correlated with concentrations detected in the wastewater effluent. No seasonal difference was detected in concentrations of E. coli or FRNA bacteriophage detected in oysters.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, School of Life Science and Biotechnology, Harbin Institute of Technology, Nangang District, Harbin, China.
authors.forename: John
authors.initials: J
authors.lastname: Flannery
authors.forename: Sinéad
authors.initials: S
authors.lastname: Keaveney
authors.forename: Paulina
authors.initials: P
authors.lastname: Rajko-Nenow
authors.forename: Vincent
authors.initials: V
authors.lastname: O'Flaherty
authors.forename: William
authors.initials: W
authors.lastname: Doré
mesh_terms: D000818:Animals; D001435:Bacteriophages / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D029322:Norovirus / Q000302:isolation & purification*; D010125:Ostreidae / Q000821:virology*; D060888:Real-Time Polymerase Chain Reaction; D012621:Seasons; D019562:Viral Load; D014871:Water Microbiology; D018508:Water Purification