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Here's How Your Poop Can Be An Early Signal of a Coronavirus Outbreak

Scientists say testing wastewater could give advance warning of future COVID-19 clusters. 
woman hand flush toilet after using

You wash your hands, you wear a mask. And soon you might be able to help your city slow coronavirus without deviating from your daily routine. Researchers say that testing wastewater — specifically, poop — for signs of coronavirus could provide an early alert of a COVID-19 outbreak in a community, up to seven days earlier than current methods.

That news comes from scientists at Yale University, who hypothesized that because coronavirus has been found in stool samples, testing sewage for the SARS-CoV-2 virus (the specific coronavirus that causes COVID-19) can give a glimpse of infection rates in a particular locality.

They tested "primary municipal sewage sludge" — a.k.a. what's been flushed down toilets — from a local wastewater treatment plant, and the theory checked out: the density of viral RNA in an area's wastewater allowed them to pinpoint the virus's arrival and spread in a community.

The study, which is preliminary and hasn't yet been peer reviewed, could provide epidemiologists and local officials with a new tool for managing future coronavirus outbreaks. It's believed that coronavirus has been widely spread by people who were infected but asymptomatic. And in fact, researchers found that the rise in coronavirus infection rates preceded official counts by up to a week—a time when asymptomatic people could be out in the community infecting others. So officials might be able to test wastewater to detect an outbreak-in-progress, allowing them to mitigate its severity. 

From early in the coronavirus pandemic, researchers have believed that the virus's incubation period (the time between infection and the appearances of symptoms) can be from five to 14 days. That's been the source of much trepidation among health officials as many states begin to loosen their lockdowns, reopening restaurants, bars, retailers and offices. Person-to-person contact is believed to be the primary way in which the virus has spread, and the virus's stealthy ability to jump from a symptom-free person to others raises the risk of second and third waves of infection this year.

So any advance-detection system of an outbreak would be welcomed, and the Yale scientists' discovery has rapidly progressed from an interesting theory to a partial light at the end of the tunnel. "There is real hope that this can be a sensitive, early warning" if COVID-19 begins to spread again, Peter Grevatt, CEO of the nonprofit Water Research Foundation, told Stat News on Thursday. His group is working with local labs to determine best practices for a nationwide testing network. "We hope to have results of this lab-to-lab comparison by the end of the summer," he said.

And to get through this pandemic at your healthiest, don't miss these Things You Should Never Do During the Coronavirus Pandemic.

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