a pet.

But you don't want to be too mainstream about it, so instead of a nice dog or cat you opt

for a rat- hey, rats can be cute too you know.

You and your rat, Wilbur, quickly become best of friends, but then one day your best rat

buddy picks up an unwanted hitch hiker- a flea.

Then Wilbur's flea decides that it'd like to take a chomp out of you, and without you

even feeling it, the tiny flea has bitten you and sucked on your blood.

For the next three days you and Wilbur continue your best friendship, going on best friend

adventures and solving mysteries together- then on the fourth day you start to not feel

so hot.

You chalk it up to all the excitement you and Wilbur have been sharing lately, but as

the symptoms progress you start to feel like you might have the flu instead.

Then suddenly you start growing what look like huge blisters in your armpits and groin,

and the tips of your fingers turn black as the flesh begins to die!

Congratulations, because you've got the bubonic plague and much like most of Europe back in

the 1300s, you're about to be dead.

The plague, or black death as it is most commonly known, has its origins amongst the fleas of

rodents from the Central and Western Asian region of the world.

It's believed that climate change during a period of warming during the medieval ages

caused the rodents who carried the infected fleas to flee the drying up grasslands, while

those rodents who didn't believe in climate change stayed behind and died.

Forced into close contact with humanity, the fleas of these rodents began to feast on our

soft, supple human flesh, and in return infected us with the plague.

Historians believe that the plague killed off many early populations of humans before

naturally receding, but what would come to be known as the Black Death kicked off in

earnest early in the 1300s.

A secession of natural disasters and lesser plagues hit south and central asia, which

led to widespread famine.

Not wanting to be left out of the 'kill all humans' party, the bubonic plague arrived

in 1331, and is believed to have killed 25 million Chinese people before it finally reached

Constantinople in 1347.

Mongol raids and travelers along the famous silk road are believed to have pushed the

disease further and further west, but it wasn't until Genoese traders brought plague-infected

fleas into the port city of Kaffa in Crimea in 1347 that the bubonic plague went mainstream.

Pretty soon the black death, as it was known by then, was all the rage amongst Europeans,

and by 1351 it had reached as far west as Spain and as far north as Russia.

Before the black death went out of style, it had killed between 75 to 200 million people,

and it's believed that it took the world 200 years to recover the numbers lost to the disease.

In the wake of the plague, zealous persecution of various scapegoats blamed for the outbreak

led to the deaths of many thousands more, including Jews, friars, foreigners, beggars,

pilgrims, lepers, gypsies, and people who get to the front of the line at Starbucks

and have to check the menu because they still aren't sure what to order.

The plague had had such a good time in Europe though that it revisited the continent intermittently

throughout the 14th and 17th centuries, causing many hundreds of thousands of additional deaths.

In 1771 the Plague hit Moscow and killed between 50,000 and 100,000 people, or as much as 33%

of the city's population.

A hundred years before that the plague killed 100,000 in London.

Like adventurous European university students though the plague went global, and between

1500 and 1850 the plague was present in at least one location throughout the entire Islamic

world.

So you've gone and gotten yourself infected with the Black Death- because maybe modern

diseases are just too trendy for you- why is this the worst thing that could ever happen

to you?

Well, first, could it happen to you?

The answer to that question is no, humanity has long since overcome the terrible affliction

known as the Black Death and is safe from the ravages that once killed hundreds of millions

of people.

Just kidding, you can totally get the Black Death today, and if you think you're safe

in your First World life because surely it's only a disease that strikes at the most remote,

poorest regions of the world, you may want to think again.

As of 1900 the Black Death had made its way to the United States, when an epidemic struck

San Francisco and lasted until 1904, then quickly made a comeback throughout 1907 and

1908.

While that was over a hundred years ago and we have developed many drugs and treatments

for the plague, just in October of 2017 the deadliest outbreak in modern times hit Madagascar

and killed 170 people while infecting thousands more.

But that's in an island off the coast of Africa, and San Francisco was over a hundred years

in the past, surely we're safe today.

Once more, no, absolutely not, and in fact the western United States is one of the largest

geographic areas where the plague is reported in wild animals and livestock alike- so keep

that in mind next time you decide to hit up a petting zoo.

But what about the plague is so terrible?

Well, before we tell you we'll warn you to go ahead and finish eating if you were eating,

or to cancel any lunch or dinner plans you may have had coming up, because we doubt you'll

have the appetite after this episode.

It starts off with a flea bite, or perhaps a bite from an infected rodent, and then suddenly

your body is host to a nasty little bacteria called Yersinia pestis.

Our bodies however have had plenty of exposure to the plague by now, seeing as Yersinia pestis'

favorite historical past time was to murder all humans, and so the body has learned to

very quickly recognize Y. pestis from a unique molecule in its outer membrane.

Unfortunately, some time in the past Y. pestis caught on to this fact and now when it detects

a temperature of about 98.6 degrees (37 Celsius), the bacteria figures that it's inside a warm

blooded mammal.

This triggers Y. pestis to modify the structure of the give-away molecule, effectively blinding

your body's immune system to its real identity.

With your immune system fooled, Y pestis makes a mad dash for your lymph nodes- which seems

like an odd choice for an invading bacteria because your body's lymph nodes are basically

immune system fortresses, and constantly looking for foreign invaders to wipe out.

For any other bacteria this would pretty much be a suicide run, but Y pestis is basically

the Seal Team Six of bacteria.

Your body immediately tries to stop the bacteria with white blood cells, the cells responsible

for immune system response, but Y pestis responds by shooting these responding cells with an

appendage that injects toxins directly inside the cell's membrane, destroying it.

After owning the crap out of your immune system, Y pestis needs to recover by getting a hold

of some iron, and luckily for it your body is chock full of it.

Unfortunately for the bacteria, all that precious iron in your body is wrapped up in hemoglobin

and other proteins- or unfortunate for you really, because if you've learned anything

by now it's that Y pestis gets what it wants when it wants it.

While it holds the fort down in your lymph node, each bacteria releases a molecule called

yersiniabactin which has a very high affinity for iron.

The molecules cruise through your blood system on the lookout for a specific iron-rich protein

in your body called transferrin.

Once the molecules find some transferrin they literally rip the iron away from the protein,

destroying it in the process, and bringing it back home to Y pestis.

By now the plague is happily making your lymph nodes into its new home, kicking up its feet

and replicating out of control thanks to a rich supply of iron.

At this point you're definitely feeling under the weather, with general flu-like symptoms,

but if you're like most people you ignore these symptoms and push through without going

to the doctor.

In this case your failure to get checked out will be fatal, as with modern medicine the

plague can be cured in over 90% of cases if caught early.

If not, well your odds aren't very good at all.

At this point your lymph nodes begin swelling up, which create the iconic “buboes” so

characteristic of the bubonic plague.

These look like very large blisters and can appear on the arms, leg, groin, and arm-pits,

can grow to be as big as an apple!

By now you're going to have a really high fever and might even be vomiting blood, and

if any of those buboes burst open you'll be oozing pus and other disgusting fluids from

the open sores.

This can be extremely dangerous, because buboes that are burst open can lead to secondary

infections from other bacteria, but luckily for you you'll be dead long before any of

these infections can properly set in.

Gangrene can also set into extremities, and fingers and toes can blacken as the flesh

dies and eventually fall off.

Incredibly, it's not the plague that kills you though, but rather your own body that

does the deed.

With Y pestis bacteria throughout your blood stream your immune system totally loses its

cool and triggers a condition known as septic shock, causing your blood vessels to leak

which lowers blood volume, clotting, and eventually, organ failure.

Luckily though modern medicine is able to cure plague if caught quickly enough, though

many doctors today worry that the plague will very quickly begin to develop an immunity

to most of the drugs we use against it.

This has prompted a renewal of the arms race that has lasted for millennia between man

and bacteria, and it's hoped that new vaccines and antibodies can be developed to stop the

plague before it kicks off another world tour and leaves millions dead in its wake.

Where in the past the remote nature of most human villages and cities made it difficult

for the plague to be transmitted and thus limited its lethality, today's hyperconnected

world would let the plague travel around the world in as little as a day, and an outbreak

that started far overseas could be in your neighborhood by that evening.

In fact, it might already be there, and we might all be on the verge of the next huge

outbreak.

Do you think we could survive another outbreak of the plague?

Let us know in the comments!

Also, check out the brand new channel called“I Am.”

Real stories come to life as they're told from the perspective of the people who lived

it.

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