Kelleher Julie, Cyterski Mike, McMinn Brian R, Dean Stephanie, Pemberton Adin C, Willis Jessica R, Diedrich Adam, McWhorter Seth, Haugland Richard A, Shanks Orin C, Korajkic Asja
Office of Research and Development, United States Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, OH 45268, United States.
Office of Research and Development, United States Environmental Protection Agency, 960 College Station Road, Athens, GA 30605, United States.
Sci Total Environ. 2025 Feb 25;966:178741. doi: 10.1016/j.scitotenv.2025.178741. Epub 2025 Feb 8.
Recreational waters are routinely assessed by enumeration of fecal indicator bacteria, such as enterococci, but research suggests viral indicators may be better suited for recreational water quality applications. Somatic and F+ coliphage were proposed as predictors of viral pathogens in recreational waters, but concurrent measurements of enterococci and coliphages and comparisons across different risk-based beach action values (BAVs) are limited. We collected paired measurements of enterococci, E. coli, somatic and F+ coliphage from three Gulf of Mexico beaches. Enterococci (colony forming units: CFU) were enumerated on mEI agar and by qPCR (Entero1a: target sequence [TS]). E. coli was enumerated by qPCR (EC23S587, TS). Coliphages (plaque forming units: PFU) were enumerated using dead-end hollowfiber ultrafiltration and single agar layer assay. The largest correlation observed was between Entero1a and cultured enterococci (r ≥ 0.51, p ≤ 0.0001) and the smallest (r ≤ 0.01, p = 1.0) between F+ coliphage and cultured enterococci. Applying equivalent BAVs for culturable enterococci (60 CFU/100 mL), Entero1a (9658 TS per 100 mL) and suggested somatic (14 PFU/100 mL) and F+ (3 PFU/100 mL) thresholds resulted in the overall greatest agreement in beach advisory status between coliphages and Entero1a (74-82 %) and lowest between cultured enterococci and somatic coliphage (65 %). This rich data set not only provides valuable insights on the incidence of coliphage and FIB in the Gulf of Mexico but will also provide a foundation for future research on fecal source identification and water quality forecast modeling in sub-tropical marine waters.
休闲水域通常通过对粪便指示菌（如肠球菌）进行计数来评估，但研究表明病毒指示物可能更适合用于休闲水域水质评估。体细胞噬菌体和F+噬菌体曾被提议作为休闲水域中病毒病原体的预测指标，但对肠球菌和噬菌体的同步测量以及基于不同风险的海滩行动值（BAV）之间的比较却很有限。我们从墨西哥湾的三个海滩收集了肠球菌、大肠杆菌、体细胞噬菌体和F+噬菌体的配对测量数据。肠球菌（菌落形成单位：CFU）在mEI琼脂上进行计数，并通过qPCR（Entero1a：靶序列[TS]）进行检测。大肠杆菌通过qPCR（EC23S587，TS）进行计数。噬菌体（噬斑形成单位：PFU）采用死端中空纤维超滤和单层琼脂测定法进行计数。观察到的最大相关性存在于Entero1a与培养的肠球菌之间（r≥0.51，p≤0.0001），而最小相关性（r≤0.01，p = 1.0）则存在于F+噬菌体与培养的肠球菌之间。将适用于可培养肠球菌的等效BAV（60 CFU/100 mL）、Entero1a（每100 mL 9658个TS）以及建议的体细胞噬菌体（14 PFU/100 mL）和F+噬菌体（3 PFU/100 mL）阈值应用于数据后发现，噬菌体与Entero1a之间在海滩咨询状态方面的总体一致性最高（74 - 82%），而培养的肠球菌与体细胞噬菌体之间的一致性最低（65%）。这个丰富的数据集不仅为了解墨西哥湾噬菌体和粪便指示菌的发生率提供了有价值的见解，也将为未来亚热带海水粪便来源识别和水质预测模型的研究奠定基础。
