How sewage can warn us about the next pandemic
Your poop doesn’t lie. Feces and urine are useful barometers of an individual’s health because what goes into the body inevitably comes out. And thanks to advances in genomic sequencing that allow researchers to decode whatever is present in waste, researchers today can examine sewage to ascertain in real time the presence of drugs like opioids, as well as diseases like salmonella and, increasingly over the past two years, Covid-19.
The process is called wastewater surveillance, also known as wastewater-based epidemiology. What makes it such an effective method of detecting the prevalence of Covid-19 in an area is that while it can be difficult to get every person in a community to take a polymerase chain reaction (PCR) test or rapid antigen test, everyone, after all, poops. By examining the genetic sequences found in sewage, public health policymakers can passively detect whether a virus like Covid-19 is surging in an area, regardless of testing levels or hospital capacity.