Speaker 1: Welcome to brain Stuff, a production of I Heart Radio,
Speaker 1: Hey brain Stuff, Lauren Volga bam here. It's comforting to
Speaker 1: assume that once you flush the toilet, the contents are
Speaker 1: out of sight, out of mind. But what most people
Speaker 1: probably don't realize is that the stuff we flush away
Speaker 1: can tell us a lot about the health of ourselves
Speaker 1: and our community. And that stuff has proven to be
Speaker 1: a valuable resource in monitoring the coronavirus pandemic in communities
Speaker 1: around the world. It's called wastewater monitoring or wastewater based epidemiology,
Speaker 1: and since early in the pandemic, a growing number of
Speaker 1: researchers across the United States have been testing samples of
Speaker 1: untreated wastewater for coronavirus. They've found levels of the virus
Speaker 1: and sewage plants given early warning about levels of positive
Speaker 1: COVID nineteen tests in the communities they serve for. The
Speaker 1: article of this episode is based on how Stuff Work.
Speaker 1: Spoke with Devada S. Smith, PhD. And so see It,
Speaker 1: professor of microbiology at Texas and M University, San Antonio.
Speaker 1: She said, I've been teaching for a long time all
Speaker 1: the interesting things you can learn from toilets. She runs
Speaker 1: the Smith Lab, where she and her undergraduate team study
Speaker 1: comparative microbial genomics and evolution. She's also the daughter of
Speaker 1: a plumber, and she's focused much of her research into
Speaker 1: the wealth of information that goes into toilets. Our poop
Speaker 1: is made up primarily of water, but the remaining er
Speaker 1: so is a cocktail of undigested food, residue, fats, salts, mucus,
Speaker 1: and human pathogens like bacteria and viruses. If you're infected
Speaker 1: with the coronavirus that causes the COVID nineteen infection, then
Speaker 1: it'll show up in your excrement too. Everything that washes
Speaker 1: down the drains of our toilets, sinks, tubs, and street
Speaker 1: gutters travels from miles through our community sanitary sewer system
Speaker 1: into bigger and bigger sewer pipes. This ver of communal
Speaker 1: sewage flows into a local wastewater treatment facility, where it's
Speaker 1: ultimately pasteurized and the harmful material is removed. Regularly monitoring
Speaker 1: wastewater samples over the course of time enables researchers to
Speaker 1: establish a trend analysis. These analyzes have detected spikes and
Speaker 1: new variants days even weeks before COVID nineteen testing via
Speaker 1: nasal swabs could and since all cities and towns have
Speaker 1: their own sewage plants, researchers can pinpoint where spikes will
Speaker 1: be and whether a new variant is emerging as one
Speaker 1: of concern, Smith explained, imagine if you had two weeks
Speaker 1: lead time and a potential outbreak situation at a dorm
Speaker 1: or a hospital or other facility, you could potentially target
Speaker 1: your interventions and maybe reduce the impact of that outbreak.
Speaker 1: For example, communities could ramp up messaging to alert the
Speaker 1: public to practice masking, social distancing, and other measures to
Speaker 1: limit the spread of the virus, as well as encouraged
Speaker 1: testing in self isolation for those who test positive. Surveillance
Speaker 1: also gives researchers a better understanding of how the virus
Speaker 1: mutates and how those variants react to vaccines, factors that
Speaker 1: are vital to keeping the public safe. Smith said, we
Speaker 1: need to understand the virus because we don't know where
Speaker 1: it's going next. Public health officials have learned a lot
Speaker 1: about COVID nineteen by tracking the number of positive tests
Speaker 1: by county, state, country, and more. But testing has its
Speaker 1: limitations For starters, it requires people to actually get tested.
Speaker 1: Many do if they become exposed to the virus, have
Speaker 1: developed symptoms, or are required to do so for their jobs.
Speaker 1: But not everyone in a community chooses to get tested,
Speaker 1: either because they don't have health insurance, have no access
Speaker 1: to tests, aren't showing symptoms, or simply don't want to
Speaker 1: get tested. Smith said, if you don't get tested, then
Speaker 1: we don't have any data from you. But everybody poops,
Speaker 1: everybody how to go to the bathroom. So with wastewater testing,
Speaker 1: we have the data on potentially every single person in
Speaker 1: a system. Of course, not all municipalities are testing their wastewater,
Speaker 1: but many are voluntarily participating thanks to grants and other
Speaker 1: sources of funding, including the CARES Act. In September of
Speaker 1: the Centers for Disease Control and Prevention or CDC, launched
Speaker 1: the National Wastewater Surveillance Systems or NWSS to coordinate and
Speaker 1: build on the country's capacity to track the novel coronavirus
Speaker 1: in samples collected at wastewater plants across the country. As
Speaker 1: part of that project, the agency recently unveiled a new
Speaker 1: CDC COVID Data Tracker, where all the data on wastewater
Speaker 1: testing is centralized onto one dashboard for the public to view.
Speaker 1: Several municipalities have created their own dashboards to share their
Speaker 1: data and trend analyzes. The CDC expects participation in the
Speaker 1: program to grow as health departments and public health laboratory
Speaker 1: further build their capacity to coordinate wastewater surveillance. However, it's
Speaker 1: still a developing field and there are limitations. Among them,
Speaker 1: treatment plants don't capture homes on septic systems or communities
Speaker 1: served by decentralized systems that treat their own waste, such
Speaker 1: as hospitals or universities. However, many colleges and universities are
Speaker 1: collecting their own data, including Emory University, the University of Miami,
Speaker 1: and the University of Buffalo, just to name a few.
Speaker 1: And while concentrations of the virus and wastewater sampling can
Speaker 1: indicate just how impacted a community is, it can't tell
Speaker 1: the exact numbers of those infected. But having all the
Speaker 1: data on one page, literally and figuratively, can offer a
Speaker 1: better picture of how the virus is impacting our country.
Speaker 1: Of course, wastewater epidemiology is not new, We've talked about
Speaker 1: it on the show before, and virus tracking vias sewage
Speaker 1: has been going on for over fifty years. Smith said, Oh,
Speaker 1: wastewater is very sexy right now. It's all over the news.
Speaker 1: But here's the thing. People have been using wastewater surveillance
Speaker 1: for years to look for things like polio. For example,
Speaker 1: polio has been eradicated in nearly all countries thanks to
Speaker 1: the polio vaccine, but transmission is still ongoing in three
Speaker 1: countries where vaccines lag Nigeria, Afghanistan, and Pakistan. Rather than
Speaker 1: relying on reported cases of acute flaccid paralysis, a probable
Speaker 1: cause of polio, researchers have been looking in sewage to
Speaker 1: detect poliovirus shed in the feces of non paralyzed people
Speaker 1: infected with polio. Wastewater surveillance has also been used to
Speaker 1: detect other viruses such as hepatitis B and norovirus, and
Speaker 1: Smith says she's currently working to refine testing techniques to
Speaker 1: better monitor sewage plants for the flu a. Smith referenced
Speaker 1: a local sanitation utility employer who recently said to her,
Speaker 1: it's only wastewater if you don't use it. M Today's
Speaker 1: episode is based on the article hoop slutes why researchers
Speaker 1: are tracking coronavirus in Wastewater on how stuff works dot Com,
Speaker 1: written by Jennifer Walker. Journey brain Stuff is production of
Speaker 1: by Heart Radio in partnership with how stuff Works dot
Speaker 1: Com and is produced by Tyler Klang and Ramsey Yamp.
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