How our sewage is playing a key role in tracking the spread of Covid

• Video report by ITV Wales journalist Rob Shelley

A laboratory is probably one of the first places that comes to mind when thinking about studying coronavirus, but Bangor's waste treatment works has also been playing a key role in the fight against Covid.

Researchers at Bangor University started using the site, and another in Cardiff, to check the water for signs of the virus.

The idea behind the project, which has now been expanded to 48 sites across the country, is that monitoring can help track increases of the virus in communities.

Analysing the water can give scientists warning of where cases are rising a week in advance of symptoms like coughing.

"What we can do is pick up the RNA here and it tells us a week in advance of people actually showing classic symptoms, like coughing, that they've got the virus," explained Bangor University's Professor Davey Jones.

"So a week in advance we can tell policy makers that Covid is on the rise even before the clinical samples have been analysed.

"I think most of us work on the principle of flush and forget, we pull the toilet handle and we forget where that waste water goes.

"For us it's a bit like collect and discover because wastewater tells no lies."

The 48 wastewater facilities now included in the research cover every county in Wales and sewage from at least around 80% of the population. This gives scientists a health snapshot of tens of thousands of people.

Each facility has automated monitoring equipment installed to provide wastewater samples which scientists can test to give insights into the virus.

Tony Harrington from Welsh Water said the technique was extremely quick and effective.

He said: "We couldn't do it any other way or as fast, and I dare say as accurately either because we get a really good representative sample of what the population's health is through the sewer system."

The system has been rolled out across the UK since its inception at Bangor University and was key in early detection of the Omicron wave in Wales.

Health Minister Eluned Morgan said: "The wastewater data has helped us to understand how the pandemic has changed and allowed us to follow the Omicron wave through our communities.

"With the help of the scientists and water companies in Wales, we have increased the monitoring sites from 19 to 48 and introduced automatic sampling equipment providing even more detailed insights into wastewater testing compared with the methods we originally adopted."

Chief Scientific Adviser for Health Rob Orford said: "Wastewater monitoring has the potential to be representative of the true levels of COVID-19 in our communities, as it is less affected by changes to community testing policy and whether or not people get tested.

"We are keen to continue to explore how wastewater can play an important part of our future testing strategy as we begin to move from pandemic to endemic. Wastewater also has some exciting potential beyond COVID-19 and could be used to monitor the levels of many other viruses like influenza and anti-microbial resistance."