LSU Civil and Environmental Engineering Professor John Pardue is working with LSU School of Veterinary Medicine Professor Gus Kousoulas and other faculty to test wastewater from various areas of East Baton Rouge Parish to determine how many COVID-19 cases exist.
“We need an early surveillance system that can detect SARS-CoV-2 in the community that minimizes the challenges and biases of individual medical testing,” said Pardue. “We are testing daily and have initial data that is very interesting. We hope to be a key metric for any potential second wave of the virus in Baton Rouge.”
Since the virus is present in sewage, Pardue’s team collaborated with the City of Baton Rouge Department of Environmental Services to develop a testing method with samples taken from subbasins, or the sewershed, according to Louisiana State University.
This method is part of an early warning system for new cases in the community.
The first step is to take the flow-composite wastewater sample and pasteurize it, performing an RNA extraction, according to LSU. A reverse transcription is then conducted to obtain cDNA and then followed by the qPCR detection of SARS-CoV-2. Finally, the samples are tested at the GeneLab.
“COVID-19-impacted patients shed the virus in fecal matter and continue to shed the virus for up to five weeks after negative respiratory samples,” Pardue said. “One single wastewater measurement can test an area of 300,000 people or an area that has only 400 people living in it. It’s scalable and allows the researchers to know whether or not the numbers are going up or down each day.”
According to Pardue, environmental engineering faculty from universities in Houston, Oregon, and Michigan are doing similar testing.
Louisiana cities have their own individual pumping stations that collect wastewater from their area, and Baton Rouge alone has more than 500 pumping stations, so the team can get precise with sampling, added Pardue.
There is also a new station for LSU’s campus and the surrounding area, which can help track cases when students return in the fall, according to LSU.