If you’re going to take the subway, stand—don’t sit.
That’s just one pragmatic piece of advice gleaned from recent studies on the urban microbiome. Metal poles on subway trains, despite popular belief, actually host less bacterial biomass than the seats.
Taken as a whole, the bacteria, viruses, fungi, and protists that inhabit city environments could help us track disease outbreaks, improve public health, or even evaluate the effect of storms and pollution on sanitation (both of which are influenced by climate change, now labelled a major public health issue).
Experts presented some of their research at the Microbes in the City conference on June 19, hosted by the New York Academy of Sciences and New York University. Among other findings, they revealed that about 48% of the genetic material sampled from surfaces in New York City’s subway system is unidentifiable by today’s scientific standards.
Here’s Rachel Ehrenberg, writing for Nature News:
Still, trends are emerging from the global Metagenomics and Metadesign of Subways and Urban Biomes initiative (MetaSUB), which aims to characterize the genetic material found on public-transport systems in 16 world cities to elucidate the microscopic riders that share the commute. Storms leave a mark: months after New York City’s South Ferry Station was flooded in 2012’s Hurricane Sandy, it still harboured DNA from bacteria associated with cold marine environments and fish, Mason said. However, most of the bacteria in the subway were harmless Acinetobacter species and others associated with human skin.
The researchers are noticing other patterns, too. For instance, the microbial make-up of a house shifts to match the biology of a new resident merely 24 hours after move-in. (Yes, it’s that quick.) Moreover, sewage samples from 14 wastewater-treatment plants in New York City contained a “disturbing” amount of genes resistant to antibiotics, according to genomicists Susan Joseph and Jane Carlton. That’s an unsettling discovery, but if scientists know about these antibiotic-resistant microbes now, they could orchestrate a plan to safeguard humans against further de-diversification of our protective bacteria in the future.
That may entail centering urban design around what we know about the built microbiome. Hospitals are doing this already—here’s Brooke Borel, reporting for NOVA Next last year:
Research on the built microbiome is already influencing how some architects think about building design. “The lens I use in looking at buildings has gained a new dimension since becoming part of this research,” says Jeff Kline, an architectural researcher and building scientist at the BioBE Center at the University of Oregon. “Now I’m understanding, at least a little bit, about how architectural decisions about building form, organization, materials, and systems, especially ventilation, provide mechanisms that affect the composition of indoor microbiomes.”
With time, we might be able to manipulate these ecosystems in a way that is more beneficial for human health—ushering in a new era of pathogen-fighting urban design.
Photo credit: Gerhard Bos / Flickr (CC BY-NC 2.0)