17/04/2020

Wastewater testing is the latest innovative strategy to locate and eliminate COVID-19 infection clusters in the community.

Minister for Health and Wellbeing Stephen Wade said the joint initiative by SA Water and SA Health is a non-invasive way of monitoring for COVID-19, providing a tool for our public health clinicians to detect the virus on an ongoing basis.

“Through monitoring sewage, we will build a better understanding of communities to which the virus has spread, while gaining the unique ability to detect the virus if it reoccurs in the future," Minister Wade said.

SA Water Senior Manager Water Expertise and Research, Dr Daniel Hoefel, said it’s important to understand that while sewage is unlikely to contain infectious or live virus, the monitoring looks for the presence of its genetic material, viral RNA.

“By combining the collective knowledge of South Australia’s water and public health experts we are able to create in-house sewage virus detection techniques from sewage samples which will enhance our scientific prowess in the fight against COVID-19,” Dr Hoefel said.

“We know sewage monitoring has also been successfully deployed as a health surveillance tool to track the progression of gastroenteric disease in the community from pathogens such as Cryptosporidium, which also presents in faecal matter.

“Our cutting-edge laboratory is at the forefront of water quality science and the protection of public health, and our scientists share an abundance of experience which has enabled them to quickly shift their focus and develop research methodology to support the work of SA Health and our frontline staff.”

Specialised molecular techniques will be used to detect the viral RNA, along with a methodology to determine how much viral RNA is excreted in faecal matter, to enable researchers to track the progression of COVID-19 in the broader community.

SA Water’s wastewater treatment plant catchment areas will be overlaid by a heat map identifying infection ‘hotspots’ within the community to determine suitable sampling locations for affected communities, and also parts of the state where COVID-19 is yet to be detected.

The Department for Health and Wellbeing’s Principal Water Quality Adviser, Dr David Cunliffe, said South Australia is leading the way globally with patient testing for COVID-19 and the sewage monitoring program will add a new line of defence.

“We’ve already tested more than 30,000 people for the virus in South Australia, giving us one of the best testing rates in the world,” Dr Cunliffe said.

“Supplementing our ongoing testing with sewage monitoring will provide a wider snapshot of the virus’ transmission within the community and could give an early warning signal for increased prevalence, should it occur, allowing us to implement important controls to stop the spread.

“Overseas studies have also shown COVID-19 can appear in faeces within three days of infection, making the monitoring an incredibly effective tool when time is of the essence in the severity of this outbreak.”

Wastewater sampling is underway at SA Water’s Bolivar, Christies Beach, Glenelg, Port Lincoln and Angaston wastewater treatment plants, with sample analysis expected to commence in the coming weeks. This work will form part of a broader national initiative, coordinated by Water Research Australia.

There is currently no evidence from the World Health Organization to suggest people working with wastewater are at greater risk of contracting COVID-19, with strict hygiene practises and personal protective equipment used at all times while in the field and laboratory.