Expanding the wastewater-based epidemiology toolkit for monitoring COVID-19 community transmission in Canada

随着COVID-19疫情的持续，经济开始重新开放，加拿大迫切需要预警信号，以捕捉新的疫情激增。由于SARS-CoV-2是在受感染患者的粪便中发现的，因此在疫情爆发期间，在接收大量人口粪便的城市废水中也可以检测到该病毒。因此，废水中SARS-CoV-2的分子特征可能是城市一级早期爆发的有用指标。然而，在温哥华等主要城市能够利用SARS-CoV-2监测作为预测流行病学工具之前，存在一些知识空白，包括缺乏优化的病毒定量和回收，以及没有研究废水中病毒基因组多样性的方法。本研究的目的是与大温哥华合作，扩大基于废水的流行病学方法，以评估SARS-CoV-2的回收率和废水中定量的最佳实践，以及开发新的方法，用于SARS-CoV-2的宏基因组测序。大都会温哥华将利用研究结果向加拿大公共事业部门通报SARS-CoV-2在废水处理中的命运，并与公共卫生机构（如BC疾病控制中心）分享数据，以增强目前COVID-19的人口模型。因此，该项目开发的方法和结果将用于监测加拿大主要城市内COVID-19的社区传播，描述污水处理过程中SARS-CoV-2的命运，提供新一波疾病的早期预警，并确定公共卫生疫情缓解措施的有效性。

As the outbreak of COVID-19 wears on and economies begin to re-open, there is a dire need for early warning signals that can catch new surges of outbreaks in Canada. Because SARS-CoV-2 is found in the stool of infected patients, the virus is also detectable in municipal wastewater receiving human waste from a larger population during an outbreak. The molecular signature of SARS-CoV-2 in wastewater therefore may be a useful indicator of early outbreaks at municipal levels. Yet, several knowledge gaps exist before major municipalities, such as Metro Vancouver, can utilize SARS-CoV-2 monitoring as a predictive epidemiology tool, including a lack of optimized viral quantification and recovery and no approaches to study the genomic diversity of the virus in wastewater. The purpose of this research is to partner with Metro Vancouver to expand wastewater-based epidemiology methodology to evaluate SARS-CoV-2 recoveries and best practices for quantification in wastewater, as well as develop new approaches for metagenomic sequencing of SARS-CoV-2 in such samples. Metro Vancouver will utilize the research results to inform the Canadian public utilities sector of the fate of SARS-CoV-2 in wastewater treatment, as well as share the data with public health agencies, such as the BC Center for Disease and Control, to augment current population modelling of COVID-19. The developed methods and results from this project will be thereby utilized to monitor community transmission of COVID-19 within a major Canadian municipality, to characterize the fate of SARS-CoV-2 during wastewater treatment, to provide an early warning of new waves of illness, and to ascertain the effectiveness of public health outbreak mitigation measures.