- The Water Research Commission is hunting for traces of the Covid-19-causing coronavirus in South Africa’s wastewater
- Studies suggest that genetic material from the virus can remain in human faeces for a number of days and that it would be possible to track disease hotspots in communities’ sewage
- The long-term goal is for this surveillance system – which when fully implemented could cost upward of R45-million – to monitor other diseases, such as measles, and the country’s dysfunctional wastewater treatment plants.
SA is looking for traces of the novel coronavirus in excrement. The Water Research Commission (WRC) on Wednesday launched a program to monitor the country’s sewerage system for remnants of the virus which have been flushed down infected people’s toilets.
Wastewater-based epidemiology is not new and is a way to monitor the health of populations through biomarkers and chemicals in communities’ sewage. In previous efforts in South Africa, researchers have been looking for the residue of drugs in people’s flushed urine.
This national surveillance program could assist health officials in tracking Covid-19 cases and mapping hotspot areas in communities, Nonhlanhla Kalebaila, a research manager at the WRC, said at the virtual launch. “We could provide a full spectrum of the diversity of virus strains in the community.”
A major part of South Africa’s strategy to manage the spread of the SARS-CoV-2 virus is to identify and isolate community outbreaks as quickly as possible. But it is limited by the availability of Covid-19 test kits, backlogs at its labs, and size of the country and population.
“In light of the lack of capacity and human testing and training, it is important to explore all tools that could offer cost effective support to combat the spread of Covid-19,” said Prof Angela Mathee, head of the Medical Research Council’s environment and health unit. Wastewater-based epidemiology could “identify hotspots, direct our limited resources to where they would be most effective”.
Studies have shown that genetic material from the virus remains in human stools for a number of days and that this can be identified in sewage.
However, to date, most studies to search for Covid-19 in wastewater have been in developed countries with reticulated sewerage. “Working out how to track Covid-19 [in human waste] in informal and rural areas might break ground on how to deal with this in the developing world,” said WRC CEO Dhesigen Naidoo. “You don’t have the convenient sampling points you’d usually use.”
WRC researchers are currently establishing a proof of concept, and aim to have pilot programmes underway within the month. They estimate that the pilot phase will cost about R1-million per province or epicentre, most of which will go towards laboratory costs. Rolling out a national waste-water surveillance system would have a price tag of about R5-million per province.
“But the final budget will depend on several factors that also differ per province,” Stanley Liphadzi, WRC Group Executive: Research & Development, told Business Insider South Africa. “Those with sewer systems will have cheaper surveillance, while those with complex systems (sewer and non-sewer or open defecation) will have more costly programmes.”
However, while the Covid-19 pandemic creates an immediate need for the system, the plan is to use the national wastewater surveillance system to improve water quality in general, officials said. The country has almost 900 wastewater treatment facilities – although many of them are dysfunctional.
“The real hope is this is a stimulus to heal a number of the other ills in the water and sanitation sector,” Naidoo said.
