The plague has been present somewhere in Europe every year between 1346 and 1671.
Just to let you know about how deadly it was, a person could be feeling completely fine
one day and the next morning, he could be dead.
So you get the point, it was really, really bad, like killed between 75 million and 200
million people in Euroasia bad.
In fact, one reason it killed so many people was because it was spreading so effectively
and people didn't know what caused it.
Some believed it was God, others thought it was just some sort of bad air.
But, all this time, nobody suspected the real cause of the black death, .... the alligators...No,
I'm just kidding, it was actually the black rat.
Well, I am kind of half-joking, because, in reality, it was the fleas on the rodents which
caused the plague.
Alright, let's end this bad joke, it was actually the bacteria called Yersinia Pestis, which
lived inside the flea, which lived on black rats, which lived near the humans.
The fleas jumped on humans and bit them, infecting them with the plague and then jumping back
on the rats.
Now, you might ask yourself: "So why were the rats so widely spread in the medieval
cities?"
Like, if there were no rats, there wouldn't have been a plague, which means 75 to 200
million people wouldn't have died, so Europe might have become overpopulated and famines
would have probably happened more often than they already did.
The answer to this is because people didn't care about the cleanliness of the cities.
Anything they found dirty, they would just dump it in the street.
This made a perfect breeding ground for rats and other rodents.
To find a rat in your home today is something very unusual, unless you have them as pets,
but hundreds of years ago, it was completely normal.
The cities were the perfect habitat for the rodents and if there is something that you
learned from this video so far, that is that where there were rats, there was also the
plague.
At the beginning of the 17th century, a new wave of the plague hit Europe again.
In France, it killed approximately 1 million people, but it mysteriously didn't affect
Paris, which was the capital of France at the time.
The residents of the city were mostly unaffected, despite it having the same rat problem as
any other big town in Europe.
So, somehow, the people of Paris managed to stay away from the plague.
Maybe they respected some hygiene measures, so the city became cleaner and rodents left,
or maybe they all stayed home and quarantined until the wave of black death passed.
Or perhaps they poisoned the rats, resulting in the fleas dying as well because you know,
fleas can't live without rats.
It's something similar to the relationship between North Korea and China.
However, if you thought one of these options was correct, well, I don't blame you,
all of them seemed valid options, except that rat poisoning, I made that up.
Alright, now, let's end the suspense, the real reason why Parisians were safe from the
plague, was because of...lemons.
Who doesn't like lemonade?
Not only is it refreshing, but it is also very healthy.
Unfortunately, these cool delicious succulent bright golden things were not very popular
during the beginning of medieval times.
Lemons were distributed widely throughout the Arab world and the Mediterranean region
between 1000 and 1150, but the first substantial cultivation began in Genoa during the 15th
century.
Before then, lemons were too expensive and the limited suitable farmland for lemon trees
had held lemonade back.
Yet one day, when one of the King Of France's chief ministers visited the city of Rome,
he saw lemonade stands everywhere.
Everyone was drinking it.
And, after he took a sip from the refreshing fragrant juice, it left him to wonder: "Why
don't we have lemonade stands in Paris?"
With this being said, because he wanted and he could, he brought his love for lemons to
Paris and not only did it become popular, but it was everywhere.
And, as I said earlier in the video, people used to throw anything into the streets, so
lemon peels were everywhere on the roads of Paris and everyone was crazy about this new
lemonade trend...
Then, the plague hit the country.
Hundreds of thousands died in the cities of France, but Paris was unaffected.
Of course, Bureaucrats and officials took credit for keeping the plague out of the city,
but the real heroes were, actually, the lemons.
You see, they contain something that is called limonene, mostly found in the lemon peels,
which humans do not normally eat.
You see where I am going here?
While the large amount of lemon peels cluttering the streets might have bothered some people,
the rats were happy about it.
Now they wouldn't have to struggle to find food anymore and, who knows, they might have
enjoyed this new flavored nutriments.
As rats ate the peels, they consumed limonene, which killed the fleas or made them leave
the rat's body.
And since fleas can't live without the rodents and the bacteria, Yersinia Pestis, can't live
without the fleas the plague was wiped out from Paris.
That's how lemonade saved tens of thousands of lives in Paris.
And if you think that this was just a coincidence and the Parisians might have had
just pure luck, well, you could be right, but it's actually proven that limonene is
a natural insecticide and insect repellent.
After centuries of researching chemical insect repellents, the US Environmental Protection
Agency still lists 15 insecticides in which limonene is the chief active ingredient, including
both general bug sprays and products for pet flea.
With this being said, summer is here, so knock back as many lemonades as you like.
But, try to remember, how lemonade might have saved Paris about 300 and something summers
ago.