School of Public Health and Community Medicine, Faculty of Medicine, University of New South Wales, Kensington NSW 2052, Australia; Sydney Water Corporation, Parramatta NSW 2124, Australia.
Water Angles Consulting, Vaucluse NSW 2030, Australia.
Water Res. 2020 May 1;174:115614. doi: 10.1016/j.watres.2020.115614. Epub 2020 Feb 13.
In the more than 15 years since its introduction, quantitative microbial risk assessment (QMRA) has become a widely used technique for assessing population health risk posed by waterborne pathogens. However, the variation in approaches taken for QMRA in relation to drinking water supply is not well understood. This systematic review identifies, categorises, and critically synthesises peer-reviewed and academic case studies of QMRA implementation for existing distributed public drinking water supplies. Thirty-nine English-language, peer-reviewed and academic studies published from 2003 to 2019 were identified. Key findings were synthesised in narrative form. The overall designs of the included studies varied widely, as did the assumptions used in risk calculation, especially in relation to pathogen dose. There was also substantial variation in the degree to which the use of location-specific data weighed with the use of assumptions when performing risk calculation. In general, the included studies' complexity did not appear to be associated with greater result certainty. Factors relating to pathogen dose were commonly influential on risk estimates whereas dose-response parameters tended to be of low relative influence. In two of the included studies, use of the 'susceptible fraction' factor was inconsistent with recognised guidance and potentially led to the underestimation of risk. While approaches and assumptions used in QMRA need not be standardised, improvement in the reporting of QMRA results and uncertainties would be beneficial. It is recommended that future authors consider the water supply QMRA reporting checklist developed for the current review. Consideration of the broad types of uncertainty relevant to QMRA is also recommended. Policy-makers should consider emergent discussion on acute microbial health-based targets when setting normative guidelines. The continued representation of QMRA case studies within peer-reviewed and academic literature would also enhance future implementation. Further research is needed on the optimisation of QMRA resourcing given the application context.
在其引入后的 15 年多时间里，定量微生物风险评估 (QMRA) 已成为评估饮用水中病原体对人群健康风险的广泛使用技术。然而，对于饮用水供应中的 QMRA 方法的变化，人们的了解还不够充分。本系统评价确定、分类和批判性综合了现有的分布式公共饮用水供应的 QMRA 实施情况的同行评议和学术案例研究。从 2003 年到 2019 年，共确定了 39 篇以英语发表的同行评议和学术研究。关键发现以叙述形式综合呈现。所纳入研究的总体设计差异很大，风险计算中使用的假设也差异很大，尤其是与病原体剂量有关的假设。在执行风险计算时，使用特定地点数据与使用假设的程度也存在很大差异。一般来说，纳入研究的复杂性似乎与其结果的确定性没有关系。与病原体剂量相关的因素通常对风险估计有影响，而剂量-反应参数的影响相对较低。在纳入的两项研究中，“易感性分数”因子的使用与公认的指南不一致，可能导致风险估计不足。虽然 QMRA 中使用的方法和假设不必标准化，但改进 QMRA 结果和不确定性的报告将是有益的。建议未来的作者考虑当前审查为 QMRA 制定的供水报告清单。还建议考虑与 QMRA 相关的广泛类型的不确定性。政策制定者在制定规范性指南时，应考虑基于急性微生物健康的目标的新讨论。在同行评议和学术文献中进一步代表 QMRA 案例研究也将增强未来的实施。鉴于应用背景，需要进一步研究 QMRA 资源的优化。
