[MUSIC PLAYING] [HORSE HOOVES CLOPPING] ALYSSA GOODMAN: In 1854, cholera
struck the city of London. Over 600 people died
in just a few weeks. Physician John Snow is often
credited with discovering that cholera is a waterborne
disease and with ending the 1854 epidemic by removing the handle from
the contaminated Broad Street Pump. The full story is much more interesting. [MUSIC PLAYING] So I've been reading about
the John Snow Pub for years. There it is. Look at that. Right here, on what used to be Broad
Street, is this fine-looking pub. There's this very inauspicious sign. It says here, "The Red Granite
kerbstone," over there, "marks the site of the
historic Broad Street Pump associated with Dr.
John Snow's discovery in 1854 that Cholera is conveyed by water." So that's a really simple summary
of the whole John Snow story. And to give you just an
overview, here's the story. So it's 1854. It's really hot and the end
of the summer in London. We're here is Soho, which was a
very crowded neighborhood filled of tenements with people
not of a lot of means. And there were a lot of people
crammed into these buildings-- many, many people to an apartment. And it's hot, and it's sweaty. And the part that you can't imagine,
looking right now-- because it's still pretty crowded; it's not that hot,
but it's still pretty crowded-- here, the street now is completely clean. We see street sweeping vehicles. We see drainage in the streets. We have sewers. None of that was true in 1854. Instead, the people who lived
in these buildings, some of them had cesspools in these
little front courtyards. And they would take their
human waste and other waste and just kind of throw it out
the window into the cesspool or bring it down to the cesspool. And then it would drain
wherever it drained. And the street-- whoa--
was not something that you could easily walk
on and keep your feet clean. Wow, that's slippery and disgusting. And so people were used to this kind
of somewhat disgusting ambiance. And people thought that when there
were terrible outbreaks of disease, especially cholera, that it was
caused by the very poisonous air at this miasma, that they called it. And the smell from all the poo and all
the animal waste was pretty horrible. And it was a pretty
sensible theory to think that that could be causing disease. But John Snow, who lived
not far from here-- we'll go there later--
was a physician in London, who was convinced that cholera, in
particular, was a waterborne disease. It was not carried in this smelly air. And what happened here
on this spot in 1854 was that there was a baby who lived
at number 40 Broad Street, which would have been just about
here, baby Lewis, who came down with some sort of terrible disease
that caused really terrible diarrhea. And I think pretty quickly, people
realized that it was cholera and that there was going to be another
outbreak of this very terrible disease. And people started dying. So what happens? What happened was the waste
from baby Lewis and other people who became ill with the cholera--
so human vehicle matter-- mixed with the water supply that
was in a relatively shallow well. I think it was about 20 feet
down under the street right here. And then the cholera
bacteria began to multiply. And then people would
ingest the water, which provides the human intestines a place
where the bacteria multiplied fast. They need a host like that. So anyway, when people ingest
this contaminated water, they come down with cholera from
which you die in the hours to days. And John Snow, who really
was looking for a place where he could, unfortunate
circumstances as they were, have a very concentrated
outbreak of cholera where he could study the
origins of the outbreak, was interested in helping the people
but also interested immediately in collecting information about what
was going to happen in this outbreak. So he would have come over
here to this neighborhood and started canvassing all the people
around here to see who was dying and who needed help and what they
had done to possibly ingest water from the various water
supplies in the area. And right here, at a location
right near this red kerbstone, was a source of what was apparently
some very clean-tasting-- sweet-tasting, actually, water for drinking. Right here, it's called
the Broad Street Pump. And it turned out, as he started
canvassing the neighborhood, that he realized that most of
the people who had fallen ill and who were continuing to fall ill had
drunk water from the particular pump. So there were other water
problems in the neighborhood. And one of the things
that we'll see later is that, in the end, when he put all
these data together and he made a map, he had to show that this pump by
walking was the closest to almost all of the people who eventually
died-- 600-something people died in the epidemic. So even though there are other
pumps that are geographically potentially nearer to those
people, this one tasted good and was close to the
people who died by walking. So in epidemiology today, it's known
that one way to really make your case is to have exceptions
to the rules-- so people who should have died, who didn't
die, and then people who did die for no apparent reason. And so John Snow, in
his work, actually found both of those kinds of exceptions. And so one case is what people
sometimes refer to as the people who were saved by the beer. And so these were the brewery workers
who worked a few blocks from here, and drank mostly beer, and so had
a clean supply of things to drink. And the other case was the
workhouse that was near here. And these were the most
indigent potentially people in poorest of health. And so why did they live? They systematically
survived this epidemic. And part of the reason-- the main
and the most important reason-- is that the workhouse had a well, had
its own source of clean drinking water. So there are the exceptions of people
who should have died and didn't die. And then what happened
was he also found out about a family who would bring
water to a member of that family who had moved far, a couple miles,
outside of this neighborhood. And they brought her some
water, an elderly aunt. And she and her niece drank it. And those people both died. So to us, looking at modern
epidemiological methods, John Snow had plenty of evidence to
say that this water from this well contained the contaminant
that caused the disease. But it still took actually many years
until the locals believed his story. And another thing that we should
mention is that John Snow did not collect all this data himself. If you look around the
street here, you'll see that this is a
very busy neighborhood with lots and lots of people. And I think it was even busier in 1854. But it was a small contained community. And there were people, for example
like a curate, Henry Whitehead, who was a local, who kind of knew everybody. And so John Snow worked with Whitehead
and with other people in the area to really canvas the
information and collect the kind of sociological
demographic information that he needed to know who lived where,
when they died, where they likely got their water, who they talked
to, who they came in contact with, all kinds of other details
about their personal lives. And so that kind of
human data collection, in this tightly knit community,
was also really, really important. [MUSIC PLAYING]
