RE: Bounce back coming21 Jun 2023 09:48
Latest Waste Water Monitoring Weekly report for Wales published 15 June 2023, methodology shown below, as I have said previously, looks like DVRG (MWG) is most likely over engineered and simply not commercially competitive:
Background
In September 2020 Welsh Government began sampling wastewater from 19 Wastewater Treatment Works (WwTW) from
across Wales in order to detect the levels of SARS-CoV-2. Since then the programme has undertaken work not only to
expand the coverage of the wastewater monitoring but also to improve the testing methodology to make it more
representative of the catchments served.
Welsh Government intends to monitor up to 50 WwTW catchments across Wales in order to assist in the early detection
of changing viral levels and the potential scale of outbreaks to help inform any public health action taken in the
management of the pandemic and beyond.
Methods
Wastewater-Based Epidemiology (WBE) provides comprehensive public health information at a community level. To
achieve this, wastewater samples are collected at the inflow of sewage treatment plants across Wales. The samples are
then analysed to determine the levels of specific pathogens, as well as summarising their physico-chemical characteristics.
This data is then mapped against known infection rates and other public health indicators at the regional level.
Individuals with COVID-19 shed SARS-CoV-2 genetic material in their faeces in the form of ribonucleic acid (RNA),
regardless of whether they have symptoms or not. Measurements quantify the amount of viral RNA present in
wastewater alongside the presence of different mutations associated with SARS-CoV-2. This information therefore
provides a representative and unbiased snapshot of the level of COVID-19 infection within a community at any point in
time. In summary, WBE has the potential to act as key capability to aid in the surveillance and control of COVID-19.
Currently, a mixture of ‘composite’ and ‘spot’ samples (each comprising 1 litre of wastewater) are collected from each
WwTW 5 times a week, Monday to Friday. Spot samples are taken at the same time each day to capture peak flow, while
composite samples are collected over a 24-hour period at 15-minute intervals using automatic sampling machines. Welsh
Government currently investigates levels of COVID-19 in wastewater at 47 sites across Wales within the Dŵr Cymru Welsh
Water (DCWW) and Hafren Dyfrdwy networks