Report by Linda Geddes in the 20th May 2021 edition of The Guardian
Wastewater monitoring is being used to identify cases of the India variant and track its spread, the health secretary, Matt Hancock, has said. Although coronavirus predominantly infects cells lining the respiratory tract, it is also shed in the faeces of some infected individuals. By collecting sewage samples from wastewater treatment plants, scientists can use PCR (polymerase chain reaction) machines to detect and quantify the amount of RNA (ribonucleic acid) from Sars-CoV-2 in different areas – including new variants, such as B.1.617.2.
The wastewater scheme was piloted last summer, and has been expanded to include hundreds of sites across the UK. Hancock told MPs that testing and vaccinations were being boosted in six areas because wastewater analysis had identified places where the India variant was being transmitted. Wastewater monitoring can be used to understand where specific variants are circulating, and to provide an early warning of escalating cases in specific geographical areas.