The Ghost Map: The Story of London's Most Terrifying Epidemic--and How It Changed Science, Cities, and the Modern World

by Steven Johnson

But the experience was largely dominated by one hideous process: vast quantities of water being evacuated from his bowels, strangely absent of smell and color, harboring only tiny white particles.

Once you began emitting rice-water stools, odds were you’d be dead ...

“While the mechanism of life is suddenly arrested, the body emptied by a few rapid gushes of its serum, and reduced to a damp, dead…mass, the mind within remains untouched and clear,—shining strangely through the glazed eyes, with light unquenched and vivid,—a spirit, looking out in terror from a corpse.”

Mr. G’s heart stopped beating, barely twenty-four hours after showing the first symptoms of cholera. Within a few hours, another dozen Soho residents were dead.

Cholera is a species of bacterium, a microscopic organism that consists of a single cell harboring strands of DNA.

In terms of sheer numbers, bacteria are by far the most successful organisms on the planet.

All organisms based on the complex eukaryotic cell (plants, animals, fungi) survive thanks to one of two basic metabolic strategies: photosynthesis and aerobic respiration.

beneath all that diversity lie two fundamental options for staying alive: breathing air and capturing sunlight.

With the exception of a few unusual compounds (among them snake venom), bacteria can process all the molecules of life, making bacteria both an essential energy provider for the planet and its primary recycler.

The technical name for the cholera bacterium is Vibrio cholerae.

You need somewhere between 1 million and 100 million organisms, depending on the acidity of your stomach, to contract the disease.

A glass of water could easily contain 200 million V. cholerae without the slightest hint of cloudiness.

For those bacteria to pose any threat, you need to ingest the little creatures: simple physical contact can’t get you sick.

First, a protein called TCP pili helps the bacteria reproduce at an astonishing clip, cementing the organisms into a dense mat, made up of hundreds of layers, that covers the surface of the intestine.

The cholera toxin ultimately disrupts one of the small intestine’s primary metabolic roles, which is to maintain the body’s overall water balance.

In a healthy, hydrated body, the small intestine absorbs more water than it secretes, but an invasion of V. cholerae reverses that balance: the cholera toxin tricks the cells into expelling water at a prodigious rate, so much so that in extreme cases people have been known to lose up to thirty percent of body weight in a matter of hours.

The expelled fluids contain flakes from the epithelial cells of the small intestine (the white particles that inspired the “rice water” description). They also contain a massive quantity of V. cholerae.

The organism effectively converts the human body into a factory for multiplying itself a millionfold. And if the factory doesn’t survive longer than a few days, so be it. There’s usually another one nearby to colonize.

The first significant effect of serious dehydration is a reduction in the volume of blood circulating through the body,

The lowered volume causes the heart to pump faster to maintain blood pressure and keep vital organs—the brain and the kidneys—functional.

nonvital organs such as the gallbladder and spleen be...

Blood vessels in the extremitie...

Eventually, the heart fails in its ability to maintain adequate blood pressure, and hypotension sets in.

waste products accumulate in the blood, fostering a condition called uremia. The victim slips into unconsciousness, or even a coma; the vital organs start to shut down. Within a matter of hours, the victim is dead.

Put the organism in its desired environment, and the world will have more of that particular creature; take it out, and the world will have less.

an infected person emits the bacteria during one of the violent bouts of diarrhea that are the disease’s trademark, and another person somehow ingests some of the bacteria, usually through drinking contaminated water.

without a widespread practice of consuming other people’s waste, cholera stayed close to its original home in the brackish waters of the Ganges delta, surviving on a diet of plankton.

The sanitary conditions of Delhi could directly affect the conditions of London and Paris. It wasn’t just mankind that was being unified; it was also mankind’s small intestine.

Inevitably, in these sprawling new metropolitan spaces, with their global networks of commerce, lines were crossed: drinking water became laced with sewage.

In the invisible kingdom of viruses and bacteria, genes move in a far more indiscriminate fashion, creating many disastrous new combinations, of course, but also spreading innovative strategies at a much faster clip.

In environments where the risk of transmission is low, the better strategy is to pursue a low-intensity attack on the human host: reproduce in smaller numbers, and keep the human alive longer,

But a dense urban settlement with contaminated water supplies eliminates V. cholerae’s dilemma.

there’s every likelihood that the evacuations from the current host will be swiftly routed into the intestinal tract of a new one.

The tragic irony of cholera is that the disease has a shockingly sensible and low-tech cure: water. Cholera victims who are given water and electrolytes via intravenous and oral therapies reliably survive the illness,

Despite all the technological advances of the Industrial Age, Victorian medicine was hardly a triumph of the scientific method.

Ordinary people had long cultivated their folk remedies and homespun diagnoses, but until newspapers came along, they didn’t have a forum beyond word of mouth to share their discoveries.

There was a growing medical establishment—best embodied by the prominent journal The Lancet—but its authority was hardly supreme.

newspapers of the day were filled with sometimes comic, and almost always useless, promises of easy cures for diseases that proved to be far more intractable than the quacks suggested.

You can see in these sentences the beginning of another modern sensibility: the outrage that is now directed against the price gouging of multinational drug companies.

in this elaborate mix of homespun remedies, commercial elixirs, and pseudoscientific prescriptions you would almost never find the real advice that the patients needed to hear: rehydrate.

Hundreds of residents had been seized by the disease within a few hours of one another, in many cases entire families, left to tend for themselves in dark, suffocating rooms.

It occurred to Whitehead that, contrary to the prevailing wisdom, the sanitary conditions of the homes seemed to have no predictive power where the disease was concerned.

He detected these early patterns in the disease’s course precisely because he possessed such a fine-grained understanding of the environment:

Rogers had seen cholera outbreaks before, but already it was clear that something exceptional was under way in Golden Square.

sufferers were going from complete health to death in twelve hours.

By Sunday morning, a strange quiet had overtaken the streets of Soho.

The most common sight on the streets were the priests and doctors making their frantic rounds.

The idea that the cholera outbreak was rooted in the social conditions of these impoverished workers—and not in any innate susceptibility to the disease—lodged in the back of Snow’s mind as the cholera ran its course.

The Victorian medical refrain was, essentially: Take a few hits of opium and call me in the morning.

Snow would continue to work as a practicing physician for the rest of his life, but his eventual fame would come from his pursuits outside the consulting room.