Last reviewed 14 June 2021

Testing sewage for Covid-19 and variants now covers more than two-thirds of the population of England, the Department of Health and Social Care has confirmed, with one of the biggest wastewater processing labs in the world recently opened in Exeter.

Analysts from the Joint Biosecurity Centre (JBC) are using the insights gained to help build a better picture of where the virus is circulating, particularly asymptomatic Covid-19 infections that may otherwise go undetected.

Increased genomic sequencing of sewage samples will provide more clues to where variants of concern may be circulating undetected in communities. It can pick up evidence of variants from infected people and continue to monitor sewage after surge testing has ended in an area.

The JBC shares its findings with local authorities, NHS Test and Trace and Public Health England, which take action to prevent outbreaks.

Insights from the programme have already been used in Bristol and Luton to provide timely understanding of the spread of variants in their communities and to help to provide reassurance that local outbreak control measures are working.

Programme lead at the JBC, Dr Andrew Engeli, said: “Testing wastewater for traces of Covid-19 gives us an overall picture of national and local infection rates and is a great complement to the work that happens in the wider NHS Test and Trace programme.”

Wastewater samples are taken from around 500 locations in England as part of the Environmental Monitoring for Health Protection Programme. There are also pilots analysing the wastewater from specific institutions such as within the food supply chain and prisons.

Environment Agency Chief Executive James Bevan said: “We can learn a huge amount about community health from wastewater monitoring, and the benefits of this programme will last for years to come.”