Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an area-specific QMRA model on four pathogens, using fecal indicator concentrations (E. coli, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coli and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment, locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment.

定量微生物风险评估（QMRA）支持的剖析沐浴水是WHO对《欧洲沐浴水指令》 2020/2021修订建议的关键。我们使用粪便指示剂浓度（大肠杆菌，肠球菌）来计算四种病原体，从而开发出针对四种病原体的区域特定QMRA模型。发现疾病主要归因于人类腺病毒，其次是沙门氏菌，弧菌和诺如病毒。总体而言，累积疾病风险显示中位数约为1例/ 10000次暴露。风险评估受到所用指标的强烈影响，表明需要对粪便污染的不同来源进行更详细的调查。通过对大肠杆菌和肠球菌浓度的累积风险进行建模，以风险为基础估算粪便指标的特定区域阈值。为了改善沐浴水评估，我们建议考虑源头分配，局部估计病原体/指标比率以及根据风险评估计算特定地点的指标阈值。