National COVID-19 Wastewater Epidemiology Surveillance Programme (N-WESP)

Wastewater-Based Epidemiology (WBE) requires relatively few resources compared to the systematic testing of populations. WBE is especially promising for novel infectious diseases, where asymptomatic cases might play a significant role in transmitting the virus. However, WBE is only now being used to monitor the spread of a pandemic infectious disease. Early studies by ourselves and others have shown that SARS-CoV-2 RNA can be recovered from wastewater, including from wastewater treatment plants (WWTP) preceding local COVID-19 hospitalisation activity. Given the challenge of making available diagnostic tests to the entire UK population, WBE represents a potentially low-cost and immediate mechanism for understanding levels of infection within large geographic areas. N-WESP aims to compare our methods with those of European & North American WBE teams in an inter-lab trial for understanding, supporting and improving the DEFRA COVID-19 measurements which will feed into the Joint Biosecurity Centre (JBC). We will also compare methods with DEFRA, the EA's and JBC whilst they explore options for finer geographical measurements. N-WESP will empower public health authorities with an optimised surveillance tool with maximal sensitivity and predictive power whose uncertainties have been well characterised. N-WESP will determine whether SARS-CoV-2 RNA in wastewater and sludge is infectious, and to what extent there might be downstream risks to human health. N-WESP will exploit catchment and, uniquely, sub-catchment-scale longitudinal surveillance to understand temporal and spatial heterogeneity, relationships to human disease burden distribution and whether there is potential outbreak 'hotspots' by surveilling sewer system nodes.