Rector Annabel, Bloemen Mandy, Thijssen Marijn, Delang Leen, Raymenants Joren, Thibaut Jonathan, Pussig Bram, Fondu Lore, Aertgeerts Bert, Van Ranst Marc, Van Geet Chris, Arnout Jef, Wollants Elke
Laboratory of Clinical and Epidemiological Virology, Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, Leuven, Belgium.
Laboratory of Virology and Chemotherapy, Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, Leuven, Belgium.
J Med Virol. 2023 Feb;95(2):e28587. doi: 10.1002/jmv.28587.
Wastewater surveillance plays an important role in the management of the coronavirus disease 2019 (COVID-19) pandemic all over the world. Using different wastewater collection points in Leuven, we wanted to investigate the use of wastewater surveillance as an early warning system for an uprise of infections and as a tool to follow the circulation of specific variants of concern (VOCs) in particular geographic areas. Wastewater samples were collected from local neighborhood sewers and from a large regional wastewater treatment plant (WWTP) in the area of Leuven, Belgium. After virus concentration, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was quantified by real-time quantitative polymerase chain reaction (RT-qPCR) and normalized with the human fecal indicator pepper mild mottle virus (PMMoV). A combination of multiplex RT-qPCR assays was used to detect signature mutations of circulating VOCs. Fecal virus shedding of SARS-CoV-2 variants was measured in feces samples of hospitalized patients. In two residential sampling sites, a rise in wastewater SARS-CoV-2 concentration preceded peaks in positive cases. In the WWTP, viral load peaks were seen concomitant with the consecutive waves of positive cases caused by the original Wuhan SARS-CoV-2 strain and subsequent VOCs. During the Omicron BA.1 wave, the wastewater viral load increased to a lesser degree, even after normalization of SARS-CoV-2 concentration using PMMoV. This might be attributable to a lower level of fecal excretion of this variant. Circulation of SARS-CoV-2 VOCs Alpha, Delta, Omicron BA1/BA.2, and BA.4/BA.5 could be detected based on the presence of specific key mutations. The shift in variants was noticeable in the wastewater, with key mutations of two different variants being present simultaneously during the transition period. Wastewater-based surveillance is a sensitive tool to monitor SARS-CoV-2 circulation levels and VOCs in larger regions. In times of reduced test capacity, this can prove to be highly valuable. Differences in excretion levels of various SARS-CoV-2 variants should however be taken into account when using wastewater surveillance to monitor SARS-CoV-2 circulation levels in the population.
废水监测在全球2019冠状病毒病（COVID-19）大流行的管理中发挥着重要作用。我们利用鲁汶的不同废水收集点，想要研究将废水监测作为感染上升的预警系统以及追踪特定关注变异株（VOCs）在特定地理区域传播情况的工具。废水样本取自比利时鲁汶地区当地社区的下水道以及一个大型区域污水处理厂（WWTP）。病毒浓缩后，通过实时定量聚合酶链反应（RT-qPCR）对严重急性呼吸综合征冠状病毒2（SARS-CoV-2）RNA进行定量，并用人粪便指示病毒辣椒轻斑驳病毒（PMMoV）进行标准化。使用多重RT-qPCR检测组合来检测循环VOCs的特征性突变。在住院患者的粪便样本中测量SARS-CoV-2变异株的粪便病毒排泄量。在两个住宅采样点，废水SARS-CoV-2浓度的上升先于阳性病例的峰值出现。在污水处理厂，病毒载量峰值与由原始武汉SARS-CoV-2毒株及后续VOCs引起的连续几波阳性病例同时出现。在奥密克戎BA.1毒株流行期间，即使使用PMMoV对SARS-CoV-2浓度进行标准化后，废水病毒载量的增加程度也较小。这可能归因于该变异株较低的粪便排泄水平。基于特定关键突变的存在，可以检测到SARS-CoV-2 VOCs阿尔法、德尔塔、奥密克戎BA1/BA.2和BA.4/BA.5的传播情况。变异株的转变在废水中很明显，在过渡期同时存在两种不同变异株的关键突变。基于废水的监测是监测较大区域内SARS-CoV-2传播水平和VOCs的敏感工具。在检测能力下降的时候，这可能被证明具有很高的价值。然而，在利用废水监测来监测人群中SARS-CoV-2传播水平时，应考虑各种SARS-CoV-2变异株排泄水平的差异。
