The New York Subway is without a doubt covered with the bacteria of the 5.5 million riders it carries each day. However, it has been discovered that there are other species that are riding in the underground tunnels as well. 48 percent of the molecular DNA discovered do not match any other organism known to humankind. A whole new species rides the subway every day.
October 29, 2012 Hurricane Sandy poured millions of gallons of seawater into the the Subway’s South Ferry Station. When the Metro transit authorities inspected the station, it was described as “a large fish tank”. The spillover from the New York Bay filled the tunnels with water 80 feet deep. The hurricane brought new bacteria to the subway.
A study published in Cell Systems showed the PathoMap, which was created by lead researcher,Dr.Christopher Mason, associate professor at Weil Cornell Medical College. A PathoMap is a cartographic sketch of the subway system’s microorganism populations or the New York Subway’s bacteria population. The Wall Street Journal showed maps for specific stations. All of the maps look relatively similar to each other except the shuttered tunnels of South Ferry Station.
The PathoMap began as a way to build a baseline to construct a molecular map of New York City; a bacterial map. The idea is that you would be able to zoom in and see what molecules are present at different areas of the city to classify, track and understand the dynamics of the services we all touch every day. High school students, graduate students, public health students, medical students all covered the New York subway system swabbing for bacteria for three minutes. They took the DNA they collected back to the laboratory to track and sequence. There are over 10 billion small molecules of DNA, bacteria that is all around the New York City Subway system. This bacteria is brought in by each passenger, each day. The bacteria at the South Ferry Station, however, was different.
Dr. Mason states, “some are just associated with cold marine environments.” South Ferry Station’s bacteria has unique bacteria like none other in the New York Subway stations. Several of these bacteria are from polar waters or the North Sea. These bacteria include; Pseudoalteromonas haloplanktis and Staphylococccus aureus; all of which colonize people’s skin.
P. haloplanktis spreads in Antarctic water. The bacteria found in South Ferry Station is not common to New York coastal water. The difference between the South Ferry Station’s microbiome and Brooklyn’s Gowanus Canal is called the “molecular echo”, according to Dr. Mason. The tidal surge transplanted a colony of fishy polar bugs. This is the first time scientists have had proof of this phenomenon verifying that “an environmental disaster can be rendered onto the surfaces of a given area. According to the scientific community, this has never been shown, especially in an urban environment. The key question is how long it will last,” says Dr. Mason. The closed parts of the South Ferry Station are scheduled to be open in 2016. In the meantime, New York Subway’s South Ferry Station has been scrubbed down to remove microscopic post – hurricane squatters, and arctic bacteria so the station’s commuters can start new colonies of bacteria that belong in that location.
The PathoMap does not end in New York. Dr. Mason wants to expand the project to see how the baseline changes within each city over time. Watching the bacteria’s seasonal changes in the New York Subway to see what happens to microbiome, the ecosystems of microorganisms people touch every day. Changes in the baseline could indicate changes in disease surveillance or could contextualize a bioterrorism event.
Dr. Mason wants to compare New York City’s bacteria to other cities. Work has started in Boston. There is already swabbing in Sao Paulo, Brazil, Paris, Tokyo, Hong Kong and collaborations have begun in Shanghai. There are technologies that allow one to sequence DNA in real time. Wherever there is an instance of DNA, RNA, a virus or bacteria in a city, such as the discovery in New York City, it can be tracked in real time and the response time for the instance should become much faster.
By Jeanette Smith
Photo: Metropolitan Transit Authority/Patrick Cashin – Flickr License
Photo: Serious Bacterial Bloom – Flickr License