Sewage from six London boroughs is currently being monitored and tested for signs of coronavirus to provide an early warning system for local outbreaks, including in Bexley.
The government-led project is successfully detecting traces of coronavirus in sewage, helping officials spot spikes in Covid-19 cases in areas where relatively few people were being tested, and sharing data with NHS Test and Trace.
The Environmental Department (Defra) said analysing wastewater for fragments of genetic material from the virus “is a significant step forward in giving us a clearer idea of infection rates both nationally and locally.”
Wastewater sites have been set up in Bexley, Croydon, Kingston-upon-Thames, Newham, Enfield and Hounslow, as well as locations outside the capital.
The testing has been rolled out to more than 90 waste water treatment sites across the UK in total, with data then being shared with the Joint Biosecurity Centre as part of NHS Test and Trace.
Environment secretary George Eustice said: “This is a significant step forward in giving us a clearer idea of infection rates both nationally and locally, particularly in areas where there may be large numbers of people who aren’t showing any symptoms and therefore aren’t seeking tests.
“NHS Test and Trace is able to use the science to ensure local health leads are alerted and can take action.
“We are continuing to look at how this programme can be refined as one of the many measures we’re using to slow the spread of the virus and protect local communities.”
Emma Howard Boyd, chair of the Environment Agency, said: “Sewage is a rich source of information about community health. I recently visited Starcross laboratory and saw the testing, monitoring and analysis carried out by the Environment Agency’s wastewater experts.
“I was inspired by their collaborative approach with academics, industry and government to help provide an early-warning system for local coronavirus outbreaks.”
Separate work carried out by the National Institute for Biological Standards and Control also identified coronavirus material in London sewage in February.
This was before any cases were recorded in the capital, providing further evidence of the effectiveness of wastewater monitoring to detect infection rates.
High levels of virus material were detected in March and April followed by a considerable decrease in May and June, reflecting the impact of national lockdown measures on virus transmission.
Health and social care secretary Matt Hancock said: “This initiative is just one example of how we are working across government and with local partners to find innovative, new ways to track the outbreak, slow the spread of the virus and save lives.
“Monitoring and sampling wastewater offers another tool to help us identify outbreaks early on – helping NHS Test and Trace and local authorities target hotspots quickly and effectively.
“As we see an increase in cases across the country, it remains vitally important that everyone continues to follow Hands, Face and Space, gets a test and self-isolates if they display any coronavirus symptoms and follows the advice of NHS Test and Trace.”