Wastewater testing trial examines potential to monitor spread of COVID-19

"CREW was able to facilitate this ground-breaking research by providing financial support and coordination to allow a rapid response to a wider collective effort to develop an assay to help tracking SARS-CoV-2 via municipal wastewater"

Research funded by Scotland’s Centre of Expertise for Waters (CREW) is examining the potential of wastewater testing to help monitor the spread of coronavirus in Scotland.

The analysis is being carried out by the Scottish Environment Protection Agency (SEPA) and builds on exploratory work started by Scottish Water and academic partners from the University of Edinburgh’s Roslin Institute to monitor the levels of fragments of SARS-CoV-2 ribonucleic acid (RNA) in wastewater, with the backing of the Scottish Government and Health Protection Scotland, part of Public Health Scotland.

If successful, the trial could form the basis of an ongoing monitoring programme that would provide additional information to further strengthen the nation’s Test and Protect strategy in response to the pandemic.

The trial will see samples collected by Scottish Water and its operators from incoming wastewater at public wastewater treatment works in each of the 14 NHS Scotland health board areas being analysed by SEPA. It is estimated the samples will be representative of wastewater from between 40-50 per cent of the Scottish population and could contribute to helping understand trends in the prevalence and distribution of the virus in Scotland, in combination with community testing and hospital admissions data.

The World Health Organization has said there is currently no evidence that coronavirus has been transmitted via sewerage systems. This project will track non-infective, SARS-CoV-2 RNA fragments - a genetic footprint which can be measured in sewage even after the virus has been destroyed.

On request from Scottish Water, CREW funded a pilot project that aims to determine whether viral RNA can be detected in municipal wastewater from Scottish communities and whether the detection of these viral RNA fragments in municipal wastewater has the potential to be used to track community infection.

Dr Alex Corbishley led the research from the University of Edinburgh’s Roslin Institute and CREW engaged SEPA to ensure that the methods developed could ultimately be included in their national (Scottish) programme of surveillance and analysis.

He said: “Detecting viral genetic material in wastewater is relatively easy, however the challenge is measuring how much genetic material is present accurately and relating that to disease levels in the community.

“The support from CREW has allowed us to use our expertise in disease monitoring to inform SEPA and Scottish Water’s efforts to develop a Scottish wastewater monitoring programme”.

Environment Secretary Roseanna Cunningham commented: “The COVID-19 pandemic has been an unprecedented global crisis which has fundamentally affected us all.

“There has of course been much research work carried out globally to better monitor, assess and understand the virus. Such work is crucial to ensure our recovery and I welcome this important project being undertaken by SEPA, Scottish Water, academia and other partners to monitor the prevalence of the virus across the Scottish population.”

Dr Rachel Helliwell, CREW Manager, added: “I am delighted that CREW was able to facilitate this ground-breaking research by providing financial support and coordination to allow a rapid response to a wider collective effort to develop an assay to help to track SARS-CoV-2 via municipal wastewater.

“CREW and the research team used this opportunity to further develop the network with SEPA and Heriot-Watt, and a successful funding proposal, to take the work beyond the CREW project.”

Funded by the Scottish Government, CREW is a partnership between the James Hutton Institute and Scottish higher education institutes. For details see www.crew.ac.uk.