Mass transportation systems are highly contaminated with the bacteria and viruses we carry. Rapid transportation has shrunk our world to where pathogens can move overnight across oceans, borders and vast territories. Or just across town. These systems shrink our world to where pathogens can move overnight across oceans, borders and vast territories.
The Role of Human Transportation Networks in Mediating the Genetic Structure of Seasonal Influenza in the United States is a study that investigated how human movement along the aviation and commuter networks contributed to intra-seasonal genetic structure of influenza A epidemics in the continental United States using spatially-referenced hemagglutinin nucleotide sequences collected from 2003–2013 for both the H3N2 and H1N1 subtypes.
The authors summarize that “the rapid, long-distance spread of human pathogens such as seasonal influenza A across modern transportation networks presents a tremendous challenge for public health and that the results demonstrate that genetic structure does exist for influenza populations during the course of a single season at the regional scale, highlighting the need to incorporate host movement patterns when studying spatial population structure.”
Some related pieces of interest:
- We’ve Been Looking at the Spread of Global Pandemics All Wrong – Redrawn maps of the world’s air-transport network could change the way we track disease from city to city. The idea that disease travels through airport networks is not a novel one to epidemiologists. But the discovery that pandemic patterns have not changed so much after all in the last 500 years is.
- Risk assessment guidelines for infectious diseases transmitted on aircraft (RAGIDA) – Influenza is a wonderful document produced by the European Centre for Disease Prevention and Control. The RAGIDA project combines evidence retrieved from the literature with expert knowledge for infectious diseases. In 2009 the production of the series of guidance documents for assisting in the evaluation of risk for transmission was initiated for several infectious diseases. The resulting disease-specific operational documents provide a host of viable options for decision-makers, particularly when faced with the choice of whether to contact trace air travelers and crew that were potentially exposed to infectious diseases during a flight.
- While most of the germs found on New York City subways seem to be harmless, some are. Photographer Craig Ward created this stunning visualization, called “Subvisual Subway.”
- From crossing oceans to simply traveling across town, mass transit can assist with the spread of disease. Bay Area Rapid Transit (BART) riders in the San Francisco area might have been exposed to measles.