More on this book
Community
Kindle Notes & Highlights
Read between
March 31 - April 3, 2023
To solve the riddle of cholera you had to zoom out, look for broader patterns in the disease’s itinerary through the city. When health matters are at stake, we now call this wide view epidemiology,
Epidemiology as a science was still in its infancy, and many of its basic principles had yet to be established.
At the same time, the scientific method rarely intersected with the development and testing of new treatments and medicines.
Ironically, just a few days before Snow had unsuccessfully attempted to see any telltale signs of cholera in the water, an Italian scientist at the University of Florence had discovered a small, comma-shaped organism in the intestinal mucosa of a cholera victim.
the germ theory of disease had not yet entered mainstream scientific thought, and cholera itself was largely assumed by the miasmatists to be some kind of atmospheric pollution, not a living creature.
John Snow would go to his grave never learning that the cholera agent he had spent so many years pursuing had been identified during his lifetime.
He would try to find the killer through an indirect route: by looking at patterns of lives and deaths on the streets of Golden Square.
By the mid-1840s, his reports tallied deaths not only by disease, but also by parish, age, and occupation.
Farr thought that the single most reliable predictor of environmental contamination was elevation:
This would prove to be a classic case of correlation being mistaken for causation: the communities at the higher elevations tended to be less densely settled than the crowded streets around the Thames, and their distance from the river made them less likely to drink its contaminated water.
They were safer because they tended to have cleaner water.
Farr had been intrigued enough by Snow’s waterborne theory to add a new category to his Weekly Returns.
In addition to tracking the age and sex and elevation of the cholera victims, Farr would now track one additional variable: where they got their water.
In a community lacking pure-water supplies, the closest thing to “pure” fluid was alcohol.
The water they supplied their customers was therefore contaminated by the raw waste of the city, thanks to the growing network of sewers that emptied into the increasingly foul river.
the early 1850s, Parliament passed legislation ordering that all London’s water companies had to move their intake pipes above the tidewater mark by August 1855.
If Snow’s theory was right, there should be a disproportionate fatality rate in the S&V homes, despite the fact that they existed side by side with the Lambeth homes.
roughly 1 in 100 died in the S&V subdistricts, while not a single person had died of cholera among the 14,632 Lambeth drinkers.
If Snow could find a breakdown of cholera deaths within those districts along the lines of water supplier, he might well have conclusive proof of his theory, enough perhaps to turn the tide against the miasma model.
Many residents had no idea where their water came from.
Snow had noticed that S&V water consistently contained about four times as much salt as Lambeth water. A simple test in his home lab could determine which company had supplied the water.
when the hearses came round to remove the dead, the coffins were so numerous that they were put on top of the hearses as well as the inside. Such a spectacle has not been witnessed in London since the time of the plague.”
All three of them attributed their recovery to one thing: they had consumed large quantities of water from the Broad Street pump since falling ill.
More than five hundred residents of the Golden Square neighborhood had died in five days, and another seventy-six had fallen ill the day before.
The one intervention the Board of Health had made would have been immediately and viscerally evident to anyone walking through the neighborhood: the streets had been soaked with chloride of lime,
Chadwick helped solidify, if not outright invent, an ensemble of categories that we now take for granted: that the state should directly engage in protecting the health and well-being of its citizens, particularly the poorest among them;
that a centralized bureaucracy of experts can solve societal problems that free markets either exacerbate or ignore; that public-health issues often require massive state investment in infrastructure or prevention.
But some of the most significant programs he put in place ended up having catastrophic effects.
Thousands upon thousands of cholera deaths in the 1850s can be directly attributed to decisions that Chadwick made in the decade before.
London needed a citywide sewage system that could remove waste products from houses in a reliable and sanitary fashion.
But as the city’s population exploded, and as more and more houses discharged their waste into the existing sewers, the quality of the Thames water declined at an alarming rate.
“Within a period of about six years, thirty thousand cesspools were abolished, and all house and street refuse was turned into the river.”
“The Thames is now made a great cesspool instead of each person having one of his own.”
The first defining act of a modern, centralized public-health authority was to poison an entire urban population.
The canary in the miasma coal mine should have been the sewer-hunters, who spent their waking hours exposed to the most noxious—sometimes even explosive—air imaginable.
Whenever smart people cling to an outlandishly incorrect idea despite substantial evidence to the contrary, something interesting is at work.
There may be no clearer example of miasma’s dark irony: on the very day that the outbreak in Golden Square was beginning, one of London’s most prestigious papers was urging the Board of Health to accelerate its work poisoning the water supply.
And seeing the patterns more clearly means progress, in the long run at least.
too many doors went unanswered, and the dead couldn’t report on their recent drinking habits. Personal testimony would not take him far in an evacuation zone.
Snow knew that the case would be made in the exceptions to the rule. What he needed now were aberrations, deviations from the norm. Pockets of life where you would expect death, pockets of death where you would expect life.
In his mind snow was already drawing maps.
the workhouse had a private supply from the Grand Junction Water Works, which Snow knew from his earlier research to be one of the more reliable sources of piped water.
the brewery had both a private pipeline and a well. But, they explained for the benefit of the teetotaling doctor, they rarely saw their men drink water at all. Their daily rations of malt liquor usually satisfied their thirst.
Had Susannah Eley by any chance consumed some of the water from the Broad Street pump?
Snow’s taciturn demeanor would have helped him as the brothers described their regular deliveries of pump water to Hampstead;
when the miasma theorists invoked the inner constitution to explain why half the population of a room might succumb to poisonous vapors while the other half emerged unscathed, Snow was naturally inclined to view the theory with some suspicion.
Snow was also a doctor, a trained observer of physical symptoms, and he understood that the bodily effects of a disease were likely to offer important clues about the disease’s original cause.
The respiratory system, on the other hand, was largely unaffected by cholera’s ravages. For Snow, that suggested an obvious etiology: cholera was ingested, not inhaled.
The sad irony of his argument for the waterborne theory of cholera is that he had all the primary medical explanations in place by the winter of 1848–1849, and yet they fell on deaf ears for almost a decade.
Like Henry Whitehead, Snow brought genuine local knowledge to the Broad Street case.
