title: Evaluating the occurrence of host-specific , general fecal indicators, and bacterial pathogens in a mixed-use watershed.
abstract: Fecal contamination of water is very common, and, in the United States, prevention is complicated by the colossal span of waterways (>3.5 million miles), heterogeneous sources of pollution, and competing interests in water monitoring. The focus of this study was the Upper Sugar Creek Watershed, a mixed-use watershed with many headwater streams and one of the most contaminated waterways in Ohio. Quantitative polymerase chain reaction (qPCR) and host-specific PCR for were evaluated for the potential to discern sources of fecal contamination. Pathogen-specific qPCR and culturable by most probable number (MPN) were compared at 21 established water quality monitoring sites in the watershed headwaters. Lower numbers of ruminant-specific markers were detected in the base flow water samples compared with the human-specific marker, suggesting the presence of hotspots of human fecal contamination. qPCR and MPN showed significant correlation ( = 0.57; < 0.001). Correlation between general fecal indicator and pathogen concentrations was weak or nonexistent. Coexistence of and human-specific was common ( = 0.015). qPCR may have a greater potential for predicting fecal contamination due to its sensitivity, rapid analysis, and availability of host-specific assays. However, the lack of a strong correlation between pathogens and general fecal indicators suggests that assessment of health risk associated with fecal contamination will require a complement of approaches.
authors.forename: Mary
authors.initials: M
authors.lastname: Drozd
authors.forename: Natsuko N
authors.initials: NN
authors.lastname: Merrick
authors.forename: Yasser M
authors.initials: YM
authors.lastname: Sanad
authors.forename: Linda K
authors.initials: LK
authors.lastname: Dick
authors.forename: Warren A
authors.initials: WA
authors.lastname: Dick
authors.forename: Gireesh
authors.initials: G
authors.lastname: Rajashekara
mesh_terms: D004784:Environmental Monitoring; D005243:Feces / Q000382:microbiology; D006801:Humans; D016133:Polymerase Chain Reaction; D045483:Rivers / Q000382:microbiology; D060753:Water Quality