Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita-shi, Osaka 565-0871, Japan.
Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ 85724, United States.
Sci Total Environ. 2024 Dec 1;954:176702. doi: 10.1016/j.scitotenv.2024.176702. Epub 2024 Oct 5.
Wastewater-based epidemiology (WBE) requires high-quality survey methods to determine the incidence of infections in wastewater catchment areas. In this study, the wastewater survey methods necessary for comprehending the incidence of infection by WBE are clarified. This clarification is based on the correlation with the number of confirmed coronavirus disease 2019 (COVID-19) cases, considering factors such as handling non-detect data, calculation method for representative values, analytical sensitivity, analytical reproducibility, sampling frequency, and survey duration. Data collected from 15 samples per week for two and a half years using a highly accurate analysis method were regarded as gold standard data, and the correlation between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA concentrations in wastewater and confirmed COVID-19 cases was analyzed by Monte Carlo simulation under the hypothetical situation where the quality of the wastewater survey method was reduced. Regarding data handling, it was appropriate to replace non-detect data with estimates based on distribution, and to use geometric means to calculate representative values. For the analysis of SARS-CoV-2 RNA in samples, using a highly sensitive and reproducible method (non-detect rates of <40 %; ≤0.4 standard deviation) and surveying at least three samples, preferably five samples, per week were considered desirable. Furthermore, conducting the survey over a period of time that included at least 50 weeks was necessary. A WBE that meets these survey criteria is sufficient for the determination of the COVID-19 infection incidence in the catchment. Furthermore, WBE can offer additional insights into infection rates in the catchment, such as the estimated 48 % decrease in confirmed COVID-19 cases visiting a clinic following a COVID-19 legal reclassification in Japan.
基于污水的流行病学（WBE）需要高质量的调查方法来确定污水集水区感染的发生率。在本研究中，阐明了理解 WBE 感染发生率所需的污水调查方法。这一澄清是基于与确诊的 2019 年冠状病毒病（COVID-19）病例数的相关性，考虑了处理未检出数据、代表性值的计算方法、分析灵敏度、分析重现性、采样频率和调查持续时间等因素。使用高度准确的分析方法每周收集 15 个样本，持续两年半，将这些数据视为金标准数据，并通过蒙特卡罗模拟分析假设污水调查方法质量降低时污水中严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）RNA 浓度与确诊 COVID-19 病例之间的相关性。关于数据处理，用基于分布的估计值替代未检出数据，并使用几何平均值计算代表性值是合适的。对于样品中 SARS-CoV-2 RNA 的分析，使用高灵敏度和重现性的方法（未检出率<40%；≤0.4 标准差），并且每周最好至少采集三个、最好是五个样品进行分析是可取的。此外，进行至少包含 50 周的调查是必要的。满足这些调查标准的 WBE 足以确定集水区内 COVID-19 的感染发生率。此外，WBE 可以提供集水区内感染率的额外信息，例如在日本 COVID-19 重新分类后，前往诊所的确诊 COVID-19 病例估计减少了 48%。
