Oysters contaminated with human enteric viruses from sewage are implicated in foodborne outbreaks globally. Bacteriophages have been identified as potential indicators for these viruses, but have not been used in shellfish management outside of the USA. This study aimed to determine the background levels of F-RNA phage in five Australian oyster growing areas with a history of sewage spills and closures, over an 18-month period. In addition, oysters from five growing areas impacted by adverse sewage events were investigated for F-RNA phage, Escherichia coli, norovirus (NoV) and hepatitis A virus (HAV). F-RNA phage ≤ 60 pfu/100 gm shellfish flesh were found to represent a conservative background level in the surveyed areas. Following two of the five sewage spills, elevated phage levels were observed in most sample sites less than 4 days post spill. By 7 days, most sites from all events had phage < 30 pfu/100 gm. NoV was detected in day 1 and day 6 samples from one event when all phage were ≤ 30 pfu/100 gm. NoV was also detected in a day 3 sample from another event with < 30 phage pfu/100 gm, however, multiple replicate samples had elevated phage levels. The results of this study add evidence on the potential use of F-RNA phage as a tool in early re-opening of oyster harvest areas post sewage spills. However, it also highlights the need to better understand situations where phage testing may be ineffectual, and the importance of sampling at multiple sites and over multiple time points, to effectively capture evidence of contamination.

被来自污水的人类肠道病毒污染的牡蛎与全球食源性疾病暴发有关。噬菌体已被确定为这些病毒的潜在指标，但尚未用于美国以外的贝类管理。本研究旨在确定在 18 个月内有污水泄漏和关闭历史的五个澳大利亚牡蛎种植区的 F-RNA 噬菌体背景水平。此外，对来自受不良污水事件影响的五个种植区的牡蛎进行了 F-RNA 噬菌体、大肠杆菌、诺如病毒 (NoV) 和甲型肝炎病毒 (HAV) 的调查。F-RNA 噬菌体≤ 60 pfu/100 gm 贝类肉被发现代表了调查区域的保守背景水平。在五次污水泄漏中的两次之后，在泄漏后不到 4 天的时间里，在大多数样本点中观察到噬菌体水平升高。到 7 天时，来自所有事件的大多数位点的噬菌体 < 30 pfu/100 gm。当所有噬菌体≤ 30 pfu/100 gm 时，在一个事件的第 1 天和第 6 天样品中检测到 NoV。在来自另一个事件的第 3 天样品中也检测到 NoV，噬菌体 pfu < 30/100 gm，但是，多个重复样品的噬菌体水平升高。这项研究的结果增加了 F-RNA 噬菌体作为工具在污水泄漏后早期重新开放牡蛎收获区的潜在用途的证据。然而，它还强调需要更好地了解噬菌体测试可能无效的情况，