ShmoopTube

00:02

All little kids getting their shots at the doctor's office probably wish vaccines had [Doctor squirting liquid out a syringe]

00:08

never been invented...

00:09

But it’s a good thing kids’ wishes don’t usually come true. [Kid looks scared of needles]

00:13

In this case, anyway. [Kid crying]

00:15

The days before the modern vaccine were not pretty.

00:18

For most of human history, population growth and urbanization were severely limited by [People dying and gravestones popping up]

00:24

epidemic diseases.

00:25

Smallpox, the bubonic plague, cholera, syphilis, malaria, yellow fever… [Different diseases as colored slime]

00:31

We were outgunned and outnumbered by our viral enemies.

00:36

In 1348, the Black Death killed 40% of Egypt's entire population…good thing they didn’t [People become pyramids]

00:44

all need a pyramid.

00:45

In the sixteenth century, smallpox, cholera, yellow fever, and malaria killed up to 90% [Native americans dying]

00:51

of the population of the Americas.

00:53

Sure, some groups developed immunities or slick tricks to avoid disease… [People washing their hands and wearing gloves]

00:58

But mostly people just lived with the constant fear of apocalyptic outbreaks.

01:03

If we lived back then, we’d be huddled in a corner with a jumbo bottle of Purell. [Man stood next to a giant bottle of handwash]

01:08

It definitely didn't help that medieval living conditions were less sanitary than a truck

01:13

stop bathroom on I-70.

01:14

Seriously…think about what a chamber pot actually was. [Old looking chamber pots]

01:21

Smallpox was the Voldemort of infectious diseases.

01:24

It killed about 30% of the people it came in contact with, left the rest horribly scarred [Voldemort as a virus infecting people]

01:30

or blinded, and kept returning and trying to take over the world.

01:34

It was also one of the first diseases that people figured out how to fight through a [Man dressed in karate costume trying to fight smallpox]

01:38

process called inoculation, or variolation.

01:44

Variolation was sort of an early, unreliable vaccine, but it did help stave off massive [Harry potter fighting with the voldemort virus]

01:49

epidemics.

01:50

If smallpox is Voldemort, variolation is the Order of the Phoenix. [Harry Potter kills voldemort]

01:55

To inoculate someone, they had to deliberately infect that person with a mild case of smallpox.

02:01

The mild part was key. [Doctor injecting someone with smallpox]

02:04

Ya know…cuz…getting a bad case of small pox would’ve been a bad way to avoid getting

02:09

a bad case of small pox.

02:11

Okay, timeout.

02:13

Anybody eating anything?

02:14

Yeah, put that down and grab a brown paper bag… [Man puts a sandwich down and picks up a paper bag]

02:17

Cuz here come some gross details of just how variolation was accomplished.

02:22

In India and China, variolation was practiced by the 1400s.

02:26

It involved picking off smallpox scabs and then blowing the crushed scabs into a healthy [Person blowing on another person]

02:33

person's nose.

02:35

No joke.

02:36

They snorted…

02:38

Scabs.

02:39

In Europe, where variolation was adopted in the mid-eighteenth century, they usually cut

02:43

open the sores and put the puss directly into a cut on the healthy person's hand. [Person looks grossed out]

02:49

Ah, nothing like a good dose of puss in the morning right.

02:52

Though this all sounds disgusting, it wasn’t crazy.

02:56

Inoculation worked…mostly. [Man with spots on his face blames doctor]

02:59

Sometimes it killed people, because the virus was too potent…or sometimes the disease [People dropping dead in the street]

03:03

wasn't successfully introduced.

03:05

It also wore off after a few years, leaving people vulnerable again. [Virus gives people spots on their faces]

03:10

But the principle was sound…

03:12

Expose a person's immune system to a mild form of a disease, and their body will produce

03:17

smart new cells that can target that disease if they ever encounter it again. [Diagram of the body making cells to combat the disease]

03:22

It's kinda like our immune systems hang a bunch of wanted posters all over our bodies…

03:27

And then our T-cells know who to shoot on sight.

03:30

Yeah, T-cells are tough cookies like that. [T-cells shooting the disease]

Full Transcript