Alright. Let's talk about Pandemics and Science. But not in 2020. In 1854. I'd argue that this particular outbreak is one of the most important in history.

Between 1846 and 1860 there was a global pandemic of Cholera.
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London had had outbreaks, but the one that took place in Soho in 1854 was particularly bad, due to a number of factors.

But first, a little about cholera and why the developed world doesn't have out breaks of it anymore.
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Cholera outbreaks are caused by two things: a bacteria and bad sanitation. London was a hotbed of the latter at the time and Soho was particularly bad.

Cholera basically sucks water out of your body and sends it violently out your Charmin Hole.

Cholera doesn't live very long though, so it you pump enough fluids into your system you can flush the nasty buggers out pretty effectively.

This is where the sanitation comes in. Cholera kills when a person who has it drinks water contaminated by it, reinfecting themselves
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continually until they die. Not fun.

The reason this outbreak is important is because a doctor named John Snow lived nearby. The prevailing theory t the time was that disease was spread by bad air, the Miasma Theory.

Snow had doubts.
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He decided to map out where the infected lived, to see if he could find a source.

He made two surprising and important discoveries this way.

1. Though focused on Soho, there were blank areas of the map. A brewery nearby with no infections, for example.
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2. A handful of deaths were scattered in other parts of the city.

What these two things had in common was water. The brewery had its own water source, separate from the nearby neighborhood.

Several of the scattered cases could be connected, not only back to Soho, but
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to a specific well pump on what is now Broadwick Street. This particular pump had another important association with the outbreak that Snow realized: Patient Zero, a toddler if memory serves, lived and died in the house adjacent to it.

Convinced that there was something about that particular pump, Snow and Reverend Whitehead eventually talked the people of the neighborhood to allow them to remove the tap handle.

This, and some other studies led to the creation of the Germ Theory of infection
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So what had happened was that Patient Zero got infectd (somehow) and her soiled nappies were thrown into a cess pit in the basement. There were cracks in the wall that separated the basement from the well and groundwater. As the family suffered with the disease, they were

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unwittingly reinfecting the local groundwater.

For a far deeper dive check out The Ghost Map by Stephen Johnson.

/fin