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

随着新冠肺炎疫情的持续和经济开始重新开放，迫切需要能够捕捉加拿大新一轮疫情激增的早期预警信号。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，从更多人口中接收人类排泄物的城市污水中也可以检测到该病毒。因此，废水中SARS-CoV-2的分子特征可能是市政一级早期爆发的有用指标。然而，在温哥华大都会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，存在几个知识差距，包括缺乏优化的病毒量化和恢复，以及没有方法研究废水中病毒的基因组多样性。这项研究的目的是与温哥华大都会大学合作，扩大以废水为基础的流行病学方法，以评估SARS-CoV-2回收和废水中量化的最佳实践，并开发在此类样本中进行SARS-CoV-2基因组测序的新方法。温哥华地铁将利用这项研究成果向加拿大公用事业部门通报SARS-CoV-2在废水处理中的命运，并与不列颠哥伦比亚省疾病和控制中心等公共卫生机构共享数据，以增强新冠肺炎的当前人口模型。因此，该项目开发的方法和结果将被用于监测新冠肺炎在加拿大一个主要直辖市内的社区传播，确定污水处理过程中SARS-CoV-2的命运，为新的疾病浪潮提供早期预警，并确定缓解公共卫生爆发措施的有效性。

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.