Across the globe, Covid-19 detectives are finding their research united by one thing: poop. Specifically, data that can be extracted from our sewage, which can tell us a lot about how the pandemic is spreading and mutating, and how we might rein it in. Even scientists who aren’t tracking the spread of the virus via poop alone are still using this data in their models.
People mostly spread SARS-CoV-2, the virus that causes Covid-19, through the nose and mouth, but the bug also nestles in the intestines and can spread through waste. In the early days of the Covid-19 outbreak, scientists turned to raw sewage to find traces of the virus that have been missed by other detection methods, like logging hospitalizations, contact tracing, or positive tests.
Scientists regularly deploy sewage surveillance to monitor for polioviruses, pathogens with antimicrobial resistance, and even the use of drugs like heroin and MDMA. So it didn’t take much tweaking to start looking for the new coronavirus.
Wastewater-based epidemiology (WBE), the technical term for tracking pathogens in sewage, holds a lot of promise: It can supplement the shortages, delayed results, and poor quality of testing in the United States. It can potentially tell us how the virus is evolving. Because everybody poops, it can capture the scale of the virus at a population level, which is more cost-effective than testing every single resident.
And, as an experiment in the Netherlands demonstrated, it can sometimes detect the virus before hospitals. “Better population-wide data could aid in reducing the economic damage and social burden placed on populations dealing with stay-at-home ordinances, furlough, and involuntary unemployment,” an August analysis in Science of The Total Environment found.
For these reasons, and because it involves poop, this scatological investigation strategy attracted a lot of scientific and media attention when the outbreak first began. It started with a few labs collecting samples in the Netherlands, the San Francisco Bay Area, Paris, and a few…