In an effort to build an early warning system for Covid-19, the Indian Institute of Technology Gandhinagar (IIT-Gn) has joined a global consortium of 51 premier universities and research institutes to undertake surveillance of sewage water to help determine and quantify excretion of the Sars-Cov-2 virus, which causes Covid-19.
On Friday, the group submitted their viewpoint paper to Environmental Science and Technology, a scientific peer-reviewed journal published by the American Chemical Society, underlining the need to survey wastewater for virus RNA during the ongoing pandemic that has affected more than 2 million people across the world.
The aim of wastewater-based epidemiology (WBE) is to help policy makers monitor the transmission of Covid-19 within a community. “The critical point here is that while it takes three to 14 days for an individual to exhibit symptoms, its occurrence in wastewater can been seen early and therefore it can be used as a warning sign, especially in densely-populated clusters,” said Manish Kumar, collaborator and assistant professor, department of earth sciences, IIT-Gn.
The COVID-19 WBE Collaborative – a partnership between Sewage Analysis CORe group Europe (SCORE) network and the Global Water Pathogen Project – has laid out a standard protocol to ensure uniformity in data collection and inference.
Recent studies have reported that in 27% to 89% of patients, the infection is accompanied by persistent shedding of virus RNA in stool. “Wastewater has been used in forensics for a long time – to check for the presence of narcotics, for instance. However, Covid-19 is tricky because we don’t know how long the virus survives in water. But it is worth knowing its presence in wastewater because the virus has an incubation period during which it gets excreted in some way,” said Kumar.
Researchers said limited capacity for diagnostic testing coupled with individuals who are asymptomatic and oligo-symptomatic (displaying few symptoms) that go undetected leads to significant uncertainty in the estimated extent of the Covid-19 infection.
Kumar will now seek permission to collect waste water samples from government authorities in Gujarat, and partner with Indian collaborators to extend the scope of the work across India.