Testing sewage alerts us to disease in communities
The ingenuity and creativity of our scientists knows no bounds. Talk about thinking out of the box. Who would have thought that sewage could provide answers to a medical problem?
It turns out sewage could be a useful tool not only in the diagnosis of Covid-19 but also in providing data on locating virus hotspots.
A report in the BMJ by medical writer Zosia Kmietowicz explains that sewage is known to be a great way to spot the various kinds of infections and different strains of bacteria within communities.
This applies to viruses too and in particular coronavirus, says Davey Jones, professor of soil and environmental science at Bangor University.
Scientists have been collecting wastewater to check for RNA from SARS-CoV-2 in sewage since the start of the pandemic.
Jones believes sewage reflects the public’s health. If you know how to examine it, it reveals secrets. It’s been used to track antimicrobial resistance in the community, drug use and microplastics, as well as other viruses such as norovirus and hepatitis.
Sewage can act as an early warning system. By taking samples of wastewater in North Wales, Jones believes sewage helped spot the surge in cases among students in September, before they were tested.
This knowledge put scientists on the front foot to control the virus.
What’s more, further analysis will help to determine if the current lockdown measures are working.
It will also reveal whether influenza viruses are circulating so that people can know if they have Covid-19 or flu.
We already have more than 90 wastewater treatment sites in the UK, and water sampling has been rolled out to cover around 22% of the population in England. There are plans to expand this project in the future.
There’s a lot of interest in the contents of sewage and wastewater by government departments. The Joint Biosecurity Centre is conducting pilots to “test how this approach can generate targeted scientific intelligence to help health authorities make future decisions, including a s s e s s i ng how precisely wastewater can be used to identify coronavirus sources.” This information can augment the track-and-trace system to follow the virus in communities on a timely basis.
It’s a whole new world of investigation, with Jones telling the BMJ that wastewater samples are analysed within 48 hours which stands comparison with the current testing system.
Only 15% of people who were tested for Covid-19 in England in the week to 14 October received results within 24 hours, which was down from 33% the previous week.