Sakarovitch Charlotte, Schlosser Olivier, Courtois Sophie, Proust-Lima Cécile, Couallier Joanne, Pétrau Agnès, Litrico Xavier, Loret Jean-François
SUEZ, LYRE, 15 av Léonard de Vinci, 33600 Pessac, France E-mail:
SUEZ, CIRSEE, 38 rue du Président Wilson, 78230 Le Pecq, France.
J Water Health. 2022 Apr;20(4):712-726. doi: 10.2166/wh.2022.012.
SARS-CoV-2 RNA quantification in wastewater has emerged as a relevant additional means to monitor the COVID-19 pandemic. However, the concentration can be affected by black water dilution factors or movements of the sewer shed population, leading to misinterpretation of measurement results. The aim of this study was to evaluate the performance of different indicators to accurately interpret SARS-CoV-2 in wastewater. Weekly/bi-weekly measurements from three cities in France were analysed from February to September 2021. The concentrations of SARS-CoV-2 gene copies were normalised to the faecal-contributing population using simple sewage component indicators. To reduce the measurement error, a composite index was created to combine simultaneously the information carried by the simple indicators. The results showed that the regularity (mean absolute difference between observation and the smoothed curve) of the simple indicators substantially varied across sampling points. The composite index consistently showed better regularity compared to the other indicators and was associated to the lowest variation in correlation coefficient across sampling points. These findings suggest the recommendation for the use of a composite index in wastewater-based epidemiology to compensate for variability in measurement results.
污水中严重急性呼吸综合征冠状病毒2（SARS-CoV-2）RNA定量已成为监测新冠疫情的一种重要补充手段。然而，其浓度可能受到黑水稀释因子或下水道流域人口流动的影响，从而导致测量结果的误判。本研究的目的是评估不同指标在准确解读污水中SARS-CoV-2方面的性能。分析了2021年2月至9月法国三个城市每周/每两周的测量数据。利用简单的污水成分指标，将SARS-CoV-2基因拷贝浓度相对于粪便贡献人口进行标准化。为了减少测量误差，创建了一个综合指数，以同时整合简单指标所携带的信息。结果表明，简单指标的规律性（观测值与平滑曲线之间的平均绝对差）在各采样点之间有很大差异。与其他指标相比，综合指数始终表现出更好的规律性，并且在各采样点之间的相关系数变化最小。这些发现建议在基于污水的流行病学中使用综合指数，以补偿测量结果的变异性。
