This week has been pretty noisy and busy, but overall, it was good. I managed to repot some of my plants and experienced a magical summer solstice night with a beautiful full moon. I made a lot of wishes, mainly focusing on letting go of procrastination without hurting my health.
As I prep for my upcoming qualifying exams, I stumbled upon some fascinating history about the sanitation movement and felt inspired to share it. Back in the mid-19th century, Edwin Chadwick kicked off the sanitation movement in Britain. He was convinced that clean environments were key to good health and worked tirelessly to improve sanitation for everyone.
Funnily enough, John Snow was the topic of the first episode of my podcast, which I had to take down for personal reasons. In my effort to procrastinate less, I've decided to revamp my podcast and take it slow and steady this time. I’ll be doing audio-only episodes since the video aspect required a lot of effort and was the main reason I had to discontinue podcasting. So, it only makes sense to write about the history of the sanitation movement and John Snow's role in it, for Snow's groundbreaking work on cholera made the connection between water contamination and disease, further highlighting the importance of Chadwick’s efforts.
Chapter 1:Snow's Early Encounters with Cholera
John Snow, our child genius, was born into a humble family. His dad was a coal yard worker, so they weren’t exactly swimming in money. Despite this, young Snow was super smart. By the time he was 14, he had already become an apprentice to a famous physician in Newcastle. Here, as an Indian, I have to mention cholera's roots in India. Not that I am proud, but it kinda makes me feel important though. Cholera has a long history in India, with the first recorded pandemic originating in the Ganges Delta in 1817 and spreading across the world. By 1831, the epidemic had reached Newcastle, tracing a path from India to Russia to London and finally to Newcastle, most likely through trade routes.
Now, a quick note on cholera: it’s not something to mess with. Today, we have the means to save someone from cholera, but back then, people would die mainly due to dehydration, not the disease itself. The diarrhea would leave people severely dehydrated, and back then, the importance of electrolytes in rehydration therapy wasn’t discovered yet. So, despite giving fluid therapy, John Snow's patients were dropping dead.
Snow, being the meticulous apprentice that he was, documented his cases thoroughly. It reminds me of how I realized the importance of my lab notes only now, while writing a manuscript for work I did a year ago. Cleaning data sheets from last semester, I saw how much info goes undocumented and how much I've messed things up. I guess I "fucked around and found out," as they say. Not convenient, but it is what it is—I'm learning.
Snow’s careful documentation and sharp observation skills made him a great epidemiologist. He noticed a pattern in his patients' histories and started testing the waters with his initial hypothesis: maybe cholera was spreading through "miasma (bad air) in the water." He wasn’t exactly sure, but it was a start. However, people back then just shrugged and said, "You know nothing, John Snow." And the epidemic eventually passed, leaving him with more proof of his theory.
It's not until cholera returned again in 1848 that the story continues. During the pause, our man John Snow officially became a practicing physician.
Chapter 2: John Snow, The Physician
So, John Snow finally became a full-fledged physician, which gave him better access to all those cholera cases. With this new vantage point, he started noticing that a major symptom was gut-wrenching pain. Snow thought, "Hmm, maybe diarrhea isn't just a symptom; it might be how the disease spreads." He came up with this wild idea that cholera was spread by a "self-multiplying poison" in water contaminated by poop. But to keep the germ theory skeptics off his back, he wisely avoided the "G-word."
Snow decided to put his theory to the test with a little street science. He looked at households on one side of the street where the filth flowed toward their drinking water and compared them to households on the other side where the filth flowed away. The results? A starkly higher chance of dying from cholera for those unlucky enough to have their drinking water mixed with sewage. Bingo! He had cracked it: well water mixing with sewage was causing cholera all along.
Feeling pretty smug, Snow took his findings to the authorities and shared them with the public through newspapers. But guess what? They basically said, "You know nothing, John Snow." Yup, once again, no one believed him.
So, we leave our hero feeling pretty down, having failed yet again to convince the greatest minds of his time.
Chapter 3: John Snow, The Epidemiologist
By 1850, our boy John Snow had leveled up and become a founding member of the Royal Epidemiological Society of London. Epidemiology isn’t just about curing diseases; it's the deep dive into how diseases live their messy lives. Think of it as the ultimate disease stalker: figuring out where they come from, how they spread, and all the juicy details about the environmental, socioeconomic, and political factors that help them along.
Fast forward to 1854, and cholera is back with a vengeance. This time, it's not playing favorites—it's hitting everyone, rich or poor, clean or filthy. Even the staunchest supporters of the miasma theory (the idea that diseases are spread by "bad air") are starting to scratch their heads.
Our hero, now more determined than ever to prove his theory, zeros in on two companies supplying drinking water in London. Company 1 gets its water upstream, far away from the nasty sewage mixing with the Thames, while Company 2 gets it downstream, right where all the sewage party is happening. This situation is a golden opportunity for Snow to conduct the perfect case-control study.
Snow did two big things to nail his point. First, he went around collecting data about the water source of each household directly from landlords because, let's face it, the tenants had no clue where their water came from. Second, he made a map! Yes, the now-iconic field epidemiological tool in outbreak investigations.
From his collected data, Snow proved that 38 out of 44 cholera deaths were among residents who drank water supplied by the company getting it from the sewage-infested downstream of the Thames. Snow now had more proof and confidence in his hypothesis.
Armed with his data, his trusty map, and a newfound sense of determination, epidemiologist John Snow was ready to tackle the infamous cholera outbreak on Broad Street in 1854. This moment was the cornerstone for what would become the Great Sanitary Revolution. Snow's work would eventually earn him the title of the "Father of Epidemiology" and lay the foundation for the sanitary movement—the single greatest public health feat in the history of mankind.
Stay tuned as we continue the thrilling story of John Snow and how his groundbreaking work led to a revolution in public health that changed the world forever.
Yours,
nuz
Sources:
The Ghost Map by Steven Berlin Johnson
The Strange Case of the Broad Street Pump: John Snow and the Mystery of Cholera Hardcover by Sandra Hempel