Monitoring of SARS‐CoV‐2 concentration and circulation of variants of concern in wastewater of Leuven, Belgium.

AlexandrosSfakianakis shared this article with you from Inoreader Monitoring of SARS‐CoV‐2 concentration and circulation of variants of concern in wastewater of Leuven, Belgium. via Journal of Medical Virology Abstract Background Wastewater surveillance plays an important role in the management of the 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 (VOC) in particular geographic areas. Methods 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, SARS-CoV-2 RNA was quantified by 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. Results 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. Conclusions 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. This article is protected by copyright. All rights reserved. View on Web

Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.