UK-wide system to detect coronavirus in wastewater

Led by the UK Centre for Ecology & Hydrology (UKCEH), the work involves creating sampling, testing and scientific modelling methods that will be adopted by experts and government agencies as part of nationwide surveillance of Covid-19 infections. 

The team behind the project believe this method could also help reduce reliance on testing of large populations, which come with financial and logistical challenges.

The World Health Organization (WHO) has said there is currently no evidence that coronavirus has been transmitted through sewerage systems. But tests are able to detect the genetic residues of Sars-Cov-2, the virus that causes Covid-19 disease, in wastewater and those infected are thought to shed the virus in their faeces.

Dr Andrew Singer of UKCEH said: “Several studies have shown that the RNA of Sars-CoV-2 – the genetic material of the virus – can be detected in wastewater ahead of local hospital admissions, which means wastewater could effectively become the ‘canary in the coal mine’ for Covid-19 and other emerging infectious diseases.”

Scientists from the Water Research Foundation believe nationwide sewerage systems could be key to identifying future disease hotspots, holding “significant promise” for determining Covid-19 trends in different communities.

As part of the new £1m research project called the National Covid-19 Wastewater Epidemiology Surveillance Programme, the researchers will also assess the possibility for the coronavirus in wastewater and sludge to be infectious.

They believe understanding more about the infectivity of the virus in wastewater could help assess the risk to workers in sewage plants as well as to animals and people exposed to sewage discharge in rivers and seas.

Singer, who is the principal investigator of the new programme, said the research will be centred on wastewater-based epidemiology. He added the concept is based on analysis of wastewater for markers of infectious disease, illicit drugs or pharmaceuticals in order to better inform public health decisions.

“By sampling wastewater at different parts of the sewerage network, we can gradually narrow an outbreak down to smaller geographical areas, enabling public health officials to quickly target interventions in those areas at greatest risk of spreading the infection,” he explained.

Professor Barbara Kasprzyk-Hordern of the University of Bath, one of the programme’s co-investigators, explained: “Wastewater-based epidemiology offers a promising method for monitoring a pandemic, particularly for infectious diseases such as Covid-19 where asymptomatic cases play a significant role in transmitting the virus.

“Given the financial and logistical challenges of testing large numbers of people, and then trying to isolate those infected, this represents a potentially low-cost, anonymous and immediate mechanism for predicting local outbreaks and helping to contain the spread of infection.”

The programme, which is expected to last until October 2021, involves scientists from the universities of Bangor, Bath, Edinburgh, Cranfield, Lancaster, Newcastle, Oxford and Sheffield, as well as the London School of Hygiene & Tropical Medicine. 

The work is also being coordinated by the Department for Environment, Food and Rural Affairs (Defra), the Environment Agency and the Joint Biosecurity Centre working closely with water companies.

“It is heartening to see the scientific community continuing to combat coronavirus through this project, alongside the government,” said Professor Gideon Henderson, Defra’s chief scientific adviser.

Henderson added they are already working with researchers, water companies and devolved governments in Scotland, Wales and Northern Ireland to monitor for fragments of coronavirus genetic material in wastewater in the hope that it will help us detect new outbreaks.

“Though the science is still in its infancy, this new project will help us to develop the methods that we are applying,” he said. 

The research programme is funded by the Natural Environment Research Council, as part of UK Research and Innovation’s rapid response to the coronavirus outbreak.

The team will also work with scientists in other countries, including Spain and the Netherlands, where there are already-established surveillance systems to track the spread of the SARS-CoV-2 virus in sewage.

Last month, scientists from the Scottish Environment Protection Agency said they started testing sewage for traces of Covid-19 in a trial aimed at helping monitor the spread of coronavirus across Scotland. 

Back in March, University of Michigan and Stanford University researchers said they were investigating how the novel coronavirus travels through the environment, including whether it could be detected through sewage surveillance.