Since wastewater testing began for Covid-19 in early 2020, the results have helped in estimating a more accurate view of infection levels in specific areas in the UK. The discrepancy between these tests and results from COVID-19 tests highlights the level of people infected with the disease who are; pre-symptomatic, asymptomatic, or exhibiting non-specific symptoms and therefore; not requesting tests, being contacted to isolate, or informed through track and trace. This means that only a small proportion of the population is being tested for current infection with SARS-CoV-2.It is estimated that the numbers of positive cases from people with symptoms and those who have been hospitalised may only catch 20% of COVID-19 transmissions.  

 Monitoring wastewater is important in showing the overall health and levels of the virus present in a community, which can be used to help predict future breakout areas with advanced warning. Many countries have implemented, or plan to implement wastewater monitoring programmes for COVID-19,  including the UK, the Netherlands, Australia, Germany, Italy and Finland. Microorganisms and chemicals have been studied in wastewater for many years, but this new aim of monitoring for general public health is a fairly new concept. It is hoped that this approach will also be used for other diseases in the future. No infectious SARS-CoV-2 has been discovered in wastewater at this point, as it is believed that faeces and urine are unlikely to contain infectious virus, but viral genetic material fragments (RNA) have been detected and used to monitor COVID-19 levels within specific areas. Despite wastewater monitoring itself not being enough to directly infer total case numbers, it is an extremely effective measure to take alongside other initiatives like contact tracing and clinical testing. It is likely to give a wider understanding of overall community health during and after the pandemic, and is a solid line of defence against the spread of the virus.  

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Charlotte Taylor, Marketing Executive, Lab Innovations