Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA.
Soller Environmental, Berkeley, Inc., Berkeley, CA, USA.
Risk Anal. 2017 Feb;37(2):245-264. doi: 10.1111/risa.12616. Epub 2016 Jun 10.
The application of quantitative microbial risk assessments (QMRAs) to understand and mitigate risks associated with norovirus is increasingly common as there is a high frequency of outbreaks worldwide. A key component of QMRA is the dose-response analysis, which is the mathematical characterization of the association between dose and outcome. For Norovirus, multiple dose-response models are available that assume either a disaggregated or an aggregated intake dose. This work reviewed the dose-response models currently used in QMRA, and compared predicted risks from waterborne exposures (recreational and drinking) using all available dose-response models. The results found that the majority of published QMRAs of norovirus use the F hypergeometric dose-response model with α = 0.04, β = 0.055. This dose-response model predicted relatively high risk estimates compared to other dose-response models for doses in the range of 1-1,000 genomic equivalent copies. The difference in predicted risk among dose-response models was largest for small doses, which has implications for drinking water QMRAs where the concentration of norovirus is low. Based on the review, a set of best practices was proposed to encourage the careful consideration and reporting of important assumptions in the selection and use of dose-response models in QMRA of norovirus. Finally, in the absence of one best norovirus dose-response model, multiple models should be used to provide a range of predicted outcomes for probability of infection.
定量微生物风险评估（QMRAs）在理解和减轻诺如病毒相关风险方面的应用越来越普遍，因为全球范围内爆发的频率很高。QMRAs 的一个关键组成部分是剂量反应分析，这是剂量与结果之间关联的数学特征。对于诺如病毒，有多种剂量反应模型，这些模型假设摄入剂量是离散的或聚合的。本研究综述了目前在 QMRA 中使用的剂量反应模型，并比较了使用所有可用剂量反应模型的饮用水（娱乐和饮用）暴露的预测风险。结果发现，大多数已发表的诺如病毒 QMRAs 使用 F 超几何剂量反应模型，α = 0.04，β = 0.055。与其他剂量反应模型相比，该剂量反应模型对 1-1000 个基因组当量拷贝范围内的剂量预测出相对较高的风险估计。剂量反应模型之间预测风险的差异在小剂量时最大，这对饮用水 QMRAs 中诺如病毒浓度较低的情况有影响。基于综述，提出了一套最佳实践，以鼓励在诺如病毒 QMRA 中仔细考虑和报告选择和使用剂量反应模型时的重要假设。最后，在没有最佳诺如病毒剂量反应模型的情况下，应使用多种模型提供感染概率的预测结果范围。
