"The noxious vapors that cause disease, are known as miasma.
The miasma spreads through the air and as it is breathed in,
the human being becomes possessed of sickness."
"Uhm... I'm not sure that is how it works..."
"You know nothing, John Snow!"
John Snow, yes really, was no lord's son. He was born to a coal yard worker
in one of the poorest neighborhoods of York. It was 1813.
Napoleon had just retreated from Russia and the Industrial Revolution in England
was in full swing. Young Snow's mind outpaced his setting.
He was a perspicacious youth, always curious and inquisitive.
Always digging in to whatever he found.
His mother noticed her child's perpetually active mind
and swore to herself that he would be no coal hand.
She took a small inheritance that she had come into
and paid to send him to school.
He took to schooling like nothing else.
By the time he was 14, he was apprenticed to a doctor in Newcastle
and it was here that he would first meet the specter that would haunt
the rest of his life: cholera. You see, cholera had its roots in India,
but with the increase in trade and transport in the 19th century,
it crept its way up to Russia, then crawled westward through Europe.
First making its way to London and then to Newcastle in 1831.
But so many were struck so fast by the disease, that the doctor who Snow
was apprentice to was overloaded.
And so it was at the age of 18, that John Snow was sent alone into the
horror of the coal slums to treat the coal workers dying of this disease.
And make no mistake: cholera is one of the most terrifying diseases out there.
It doesn't cause the unimaginable mortality rate of the plagues, smallpox
or even some strains of influenza, but it's a horrific disease to contract.
A disease whose horror is in how it manifests,
how it takes over a person's body. It is swift and utterly wretched.
Cholera can take a healthy person, and leave them a husk overnight.
And its onset is sudden: a person can be walking down the street
and then all of a sudden they'll grab their stomach and fall to the ground
spewing vomit and diarrhea. They'll continue to expel diarrhea at up to
20 liters a day (about 5.3 gallons) until their skin becomes turgid and
their blood turns to sludge, becoming too dehydrated and thick to circulate
due to how much fluid the person's lost. Then the organs shut down one by one.
And the person dies, not directly because of an action of the disease,
but because they've lost so much fluid that their body can no longer form
the plasma it needs to keep itself alive.
And all the things John Snow had learned as an apprentice achieved nothing.
From house to house he'd walk, trying to apply every technique know to
medicine at the time to treat the sick; bleeding, opium, strong herbs to
keep off the miasma. All of these things had no effect
and patient after patient died. Even when he tried giving them water,
no mater how much water he gave them, they'd appear better for a few short
hours, then they would soon sink back down to torpor and finally death.
So despite his training, one by one as he made his rounds, he left his
patient's blue pale corpse behind.
His idea to rehydrate them was correct, but the medical community was only just
beginning to understand that the excessive diarrhea not only caused
a loss of water, but a loss of sodium as well, which is a key component
of blood plasma. And it wouldn't be until the 20th century that the major
breakthrough was made. When it was discovered that drinking glucose would
help a cholera ravaged intestinal system take up the saline it so
desperately needed. And so John Snow's patients died.
But as an apprentice, he'd kept meticulous journals with his observations
and theories. He had seen that coal workers would often be struck down by
cholera deep in the coal pits, far from the graveyards, swamps or sewage pools
that the infectious miasma was thought to seep from.
So he hypothesized that there must be something else going on.
He didn't know exactly what, but he tried to express to local doctors that,
rather than miasma, there was something. Something that could persist in water
and be transmitted from person to person that caused disease.
And they all told him: "You know nothing John Snow."
And so, as the cholera epidemic eventually passed as mysteriously
as it had come, John Snow moved on to other work.
He bounced between apprenticing for a few other doctors, until in 1836 he
went to London to begin his formal education in medicine.
And he was a man who loved education. In one year he completed the schooling
necessary to get a license as a General Practitioner.
Then he got his Apothecaries' License. Then he received a bachelor's and
a Doctorate in medicine, which apparently wasn't a requirement
for practicing medicine at the time.
And finally, he qualified to join the Royal College of Surgeons,
which is about as rad a doctor thing as you could do in those days.
During this period, John doing serious study on anesthesia.
You see, before Snow, most doctors of the day would just pour some chloroform
on a rag and toss it over their patient's face.
Nighty night! See you in a few hours, if you're lucky.
But Snow began to scientifically test dosages and assess what mixtures
at what times, were the most effective.
His work revolutionized anesthesiology.
In fact, his work was so acclaimed, he even twice anesthetized the queen herself.
And the medical community finally said: "You know something, John Snow."
But he had never forgotten cholera,
that specter that had been burned into him in his youth.
And in 1848, when John was 35, cholera returned to haunt London.
This time he was determined not to let it win.
He knew cholera wasn't just a result of bad air
And he was determined to prove it.
He reached out to all of his connections in the medical community
and tracked down the first case of the new outbreak. A sailor named John Harnold.
He had a lead! He went and immediately talked to the physician who treated
mister Harnold, only to find out that he had treated another man in the
exact same room mister Harnold rented 8 days after mister Harnold died.
The case was afoot.
John suspected contagion, perhaps from soiled bed linens that had gone unwashed
after the first death. Not miasma from some poison floating in the air.
No, this disease was transferred from one man to another.
He was sure of it. He just needed proof.
Cases began to pop up all over London
and he raced from one lead to the next.
Interviewing patients and physicians to see if he could draw the link.
He was told by one person after another that the pain started in their intestines,
which led him to believe that the disease must be caused by something
they ingested, rather than something they inhaled. Otherwise, wouldn't
the disease start in the nose or the throat or the lungs?
So, obviously not all of his reasoning was perfect,
but it did lead him down the right path in this case.
He theorized that the diarrhea caused by cholera, might not only be a symptom,
but also how the disease was spread. Now, because the term ' germs' was
frowned upon by many in the medical profession at the time, he started
writing about how cholera was caused by a 'self multiplying poison' found
in the water contaminated by fecal matter.
He did a case study. He found a street where on one side, all the waste poured
out by the residents flowed toward the well they got their drinking water from.
Whereas, on the other side, the waste flowed away from their well.
He surveyed all those living on either side of the street.
On the side where the well water mixed with the sewage, almost all of the
inhabitants were laid low. On the other side of the street, only one
person succumbed to cholera. He had it, he had his proof.
He wrote furiously. Detailing it all out and then raced to the presses.
He'd done it! His pamphlets circulated the city. The most learned minds
of the day, heard what he discovered! And they said:
"You know nothing, John Snow."
Join us next time as John Snow goes full statistical Sherlock Holmes
to show that cholera is spread through the water. And invents
the science of epidemiology in the process.