The Disease Reservoirs of the Future

[Image: Flooding in Brooklyn during Hurricane Sandy; Instagram by BLDGBLOG].

Before heading out the other night to see a panel on pandemic diseases moderated by Sonia Shah—author of the interesting new book Pandemic: Tracking Contagions, from Cholera to Ebola and Beyond—I read an otherwise unrelated article about the current rate of sea level rise.

According to a new study, the New York Times explains, sea levels are “rising faster than at any point in 28 centuries, with the rate of increase growing sharply over the past century.” Needless to say, this is having—and will continue to have—extraordinary landscape effects.

Rising sea levels are already “straining life in many towns,” the New York Times continues, “by killing lawns and trees, blocking neighborhood streets and clogging storm drains, polluting supplies of freshwater and sometimes stranding entire island communities for hours by overtopping the roads that tie them to the mainland.”

And true sea level rise has barely started.

Flooded L-train tunnel following Hurricane Sandy; photo courtesy MTA].

Recall, for example, the Guardian’s recent depiction of Miami as a city at war with the sea, as ocean water now surges into the streets from below, assaulting the surface through backed-up storm sewers.

Tidal surges are turned into walls of seawater that batter Miami Beach’s west coast and sweep into the resort’s storm drains, reversing the flow of water that normally comes down from the streets above. Instead seawater floods up into the gutters of Alton Road, the first main thoroughfare on the western side of Miami Beach, and pours into the street. Then the water surges across the rest of the island.
The effect is calamitous. Shops and houses are inundated; city life is paralysed; cars are ruined by the corrosive seawater that immerses them. During one recent high spring tide, laundromat owner Eliseo Toussaint watched as slimy green saltwater bubbled up from the gutters. It rapidly filled the street and then blocked his front door. “This never used to happen,” Toussaint told the New York Times. “I’ve owned this place eight years and now it’s all the time.”

It’s worth pointing out, of course, that Michael Grunwald, author of the excellent book The Swamp: The Everglades, Florida, and the Politics of Paradise—a Cadillac Desert for South Florida—rebutted most of that article’s more salacious points.

“I’m sorry to spoil the climate porn,” Grunwald wrote for Time, “but while the periodic puddles in my Whole Foods parking lot are harbingers of a potentially catastrophic future, they are not currently catastrophic. They are annoying. And so is this kind of yellow climate journalism.”

However, Elizabeth Kolbert recently picked up the baton in a great and convincing piece for The New Yorker. Kolbert rode around the city, speaking with geologists and water managers, visiting neighborhoods already experiencing the landscape-futures of climate change. “We’d come to a neighborhood,” she writes, “of multimillion-dollar homes where the water was creeping under the security gates and up the driveways. Porsches and Mercedeses sat flooded up to their chassis.”

Tomorrow’s coastal landscape, today.

[Image: Flooding in New York State; photo by Jonathan LaRocca/Creative Commons].

In any case, continue this trend for a century, two centuries, three centuries, and coastal cities such as Miami—and New York and Shanghai and Sydney and Lagos and Rio—are threatened not with Grunwald’s annoyance but with extinction. “Experts say the situation would then grow far worse in the 22nd century and beyond,” the New York Times points out, “likely requiring the abandonment of many coastal cities.”

None of this is news—even here on BLDGBLOG, we’ve been looking at the flooded cities of a climate-changed future since nearly day one—but it was interesting to consider this vision of a drowned world while listening to Sonia Shah and her panelists discuss known reservoirs of microbes and pathogens.

Take the Sundarbans, for example.

[Image: The Sundarbans, courtesy NASA].

In Shah’s book, Pandemic, she explains that the Sundarbans—which she describes as “a netherworld of land and sea long hostile to human penetration” in the Bay of Bengal—are the natural reservoir of Vibrio cholerae bacteria. These, of course, cause cholera.

The environmental and spatial conditions there are perfect for their survival, and it was only human intervention—and, later, global trade—that allowed cholera to make its great escape.

During the event the other night, Shah also pointed out that our mountains of impermeable plastic waste are inadvertently forming a nearly ideal, artificial ecosystem for mosquitoes, giving those insects a water-logged environment—a different kind of “plastisphere”—in which to breed. The conditions, again, are perfect for mosquitos’ survival, an accidental augmentation of their habitat by way of the consumer packaging industry.

I mention all this because it’s hard not to wonder what future disease reservoirs might form in an era of rising sea levels and flooded cities. Down in the drowned road tunnels of New York, for example, or in the geyser-like storm drains of an uninhabitable Miami—in the basements, parking lots, and silt-filled shopping malls of a submerged world—what future infections will find a route for spilling over into the human world, what disease-ridden insects find ideal conditions for replication?

These sorts of “neglected environments contaminated with human filth,” as Shah describes them, are great shapers of pandemics.

While this is not only interesting from the perspective of a potential novel plot—a Michael Crichton-like thriller set in a flood-ravaged world, where strange diseases emerge from forgotten suburbs engulfed by the sea—it also has clear epidemiological relevance, in terms of scanning ahead for potential outbreaks.

In other words, we know—as Shah’s panel the other night made abundantly clear—that human settlement in previously wild landscapes, such as deep rain forests and coastal mangrove swamps, poses predictable, if statistically complex, dangers in terms of exposing people to new diseases. But we should thus also be able to predict that certain forthcoming landscape-scale events—the permanent flooding of the New York City subway system, say, or Floridian landfills fatally overcome by rising tides—will also come with more or less known epidemiological side-effects.

Consider Bill McKibben’s recent piece in the Guardian, for example, where he writes that the Zika virus “foreshadows our dystopian climate future.” Zika, McKibben writes, is unsettling evidence that a changing climate has forced us to take “one more step in the division of the world into relative safe and dangerous zones,” suggesting “an emerging epidemiological apartheid.”

[Image: Mapping the potential future spread of malaria; UNEP/GRID].

So what are the microbes, bacteria, or pathogens—what are the insects, rodents, and invasive species—that might thrive in these as-yet unrealized landscapes? What future disease reservoirs will form, as coastal cities and towns are erased by the sea, and what are the specific thresholds that tomorrow’s epidemiologists should be looking for?

Put another way, what pandemics might emerge from these cities we know will drown?