"In their quest to detect early outbreaks, virus hunters are sampling environmental DNA in water, dirt, and air."
"It all started when Christopher Mason’s 3-year-old daughter licked a subway pole.
Like any parent, he was horrified, but also keenly curious: What types of microbes might be clinging to a metal pipe gripped by countless commuters every day?
Mason, a geneticist at Weill Cornell Medicine, soon became obsessed with that question. His toddler’s gross interlude inspired him to embark on a journey to unveil the world of bacteria, fungi, and viruses co-mingling with more than 8 million people in New York City’s urban jungle.
In 2013, he launched a project that began dispatching a small army of students shouldering backpacks crammed with latex gloves, vials, and sterile Q-tips. They sampled turnstiles, benches, and kiosks at every open metro stop in the city. It was an expedition into a largely unexplored terrain, like Mars or a deep-sea canyon, brimming with lifeforms both familiar and unknown.
The swabbers were sampling what’s called environmental DNA, or eDNA, representing the assortment of cells that all humans, animals, and microorganisms naturally shed as they go about their everyday lives, leaving genetic fingerprints. The scientists gradually quantified and mapped the unseen biological diversity — the microbiome — of the entire city. In 2015, they reported that they’d found more than 1,600 different types of microbes, nearly half of which were previously known to science. Most were harmless, associated with human skin and gastrointestinal tracts. About 12 percent were known pathogens, including fragments of genomes similar to Bubonic plague and anthrax, though there was no evidence that these small bits could make anyone sick. They hadn’t found any new deadly viruses lurking in New York’s underground — yet."
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