Harvard Researchers Are Using the T to Study Disease

Photo by Mr.TinDC on Flickr/Creative Commons

There are literally trillions of germs on the T. But before you abandon our public transit system like a disabled train at Park Street, consider this: Each bug you interact with might actually help researchers understand—and curb—disease in Boston.

That’s the hope at the Harvard T.H. Chan School of Public Health, where biologists are sampling microbes on the subway’s seats, poles, floors, and rails to understand which germs our city passes around in close quarters. Using that method, the school hopes to develop an early warning system for potential outbreaks, including the flu and antibiotic-resistant diseases.

The study’s preliminary findings, published Tuesday in mSystems, actually found surprisingly few harmful pathogens on any of the MBTA lines—which is arguably the first good news we’ve heard about the MBTA in a very long time. That preliminary reading will serve as a baseline for healthy conditions on the T; if any deviations are observed, they could lead to an early public health warning.

“We were surprised to find that the microbes that we collected on surfaces that people touch—and sometimes sneeze on—had low numbers of worrisome pathogens or antibiotic resistance genes,” senior author Curtis Huttenhower said in a statement. “These environments have drastically lower virulence profiles, in fact, than are observed in a typical human gut.”

To sample the microbes, researchers swabbed the entire interior of several T lines, as well as the screens and walls of five stations’ ticketing machines. Logically, they found that the type of surface tested was the best predictor for the type of bug living on it. For example, skin and oral microbes transferred by coughing and sneezing were present on poles and hand grips, while vaginal microbes (which can be transferred through clothing) were mostly present on seats. Little variation was found between lines and stations.

Next, Harvard researchers will explore which microbes are dead or alive, and which can be transferred between people, in order to understand how harmful pathogens persist.