"This is a sample of raw sewage, this is 40 milliliters, it came from a manhole," said Kantor showing me a small vial, "this sample could represent up to a million people."
The method works like this -- wastewater is collected over a 24-hour period, the sample is put through an 8-hour process to break down its contents, then tested for COVID-19.
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Scientists at the lab believe the method could be a promising new tool for public health agencies that have had trouble with mass testing, including long lineups and delayed results.
Already, the lab has collected more than 500 samples all over the Bay Area, many of them testing positive for the virus.
"To me it's not surprising because we know we're in a pandemic and we know people are infected, and infected people will shed the virus in their feces which is transported in the wastewater," said Kantor.
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While the virus has been found in feces, studies show that some infected people shed more than others and at different points of infection. Kantor hopes the lab's data can be just another piece in the puzzle of understanding infection rates in a community.
"The real value of this testing is that you're able to test not just asymptomatic people or pre-symptomatic people who don't know they're sick, but also people who don't have access to testing or medical care or maybe afraid to get tested," she said.
Kantor and her fellow scientists are already in communication with public health agencies in the Bay Area to discuss different ways to make use of the lab's capabilities. UC Berkeley is testing their wastewater, as well as other residential facilities. The lab is currently testing 30 samples a week but can ramp up to process 200 with a 72-hour turnaround for results.
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As Kantor and her fellow scientist refine their methods, wastewater can potentially be pinpointed to a community, a city or even an entire region.
"It will become more useful as cases go down, when it doesn't make sense to be testing everyone, all the time but we still need to be on the lookout. We still need to be watching for a fire that's starting before it spreads," she said.
"There's nothing more pressing than working to help end this pandemic. We should leave no stone unturned as we're trying to address COVID-19."
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