be spread from person to person and affects many individuals

all at the same time in a location where the disease is

not permanently prevalent.

A pandemic is like an epidemic, but is much larger in scale.

Pandemics can affect whole countries, continents,

and sometimes even the entire world.

Today, we're going to take a look

at the most destructive epidemics and pandemics

in human history.

But before we get started, be sure to subscribe

to the Weird History Channel.

After that, we'd be grateful if you'd leave a comment

and let us know what unsettling historical topics you

would like to hear about.

OK.

Ready to hear some scary stuff?

Remember, we did warn you.

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Striking at about 430 BCE during the Peloponnesian War,

the Plague of Athens took out somewhere

in the area of 100,000 people within a three year period.

If that doesn't sound too impressive,

keep in mind that's a full 25% of the entire Athenian

population of the day.

In order to help others later identify it,

the Athenian general and historian Thucydides

recorded his own eyewitness account

of the plague and its symptoms.

He described his sickness as presenting with a high fever,

diarrhea, and a pustular rash.

Equally disturbing is Thucydides' description

of the social effects of the epidemic.

He claimed that a widespread belief the plague could not

be survived caused people to start behaving

like criminals and mobs.

He wrote, "The catastrophe was so overwhelming

that men, not knowing what would happen next to them,

became indifferent to every rule of religion or law."

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Also known as the Plague of Galen,

the Antonine Plague ravaged the Roman Empire from 165 to 180

CE.

While the nature of the plague isn't known today,

it's believed that it might have been an outbreak of measles

or smallpox.

Whatever the case, historians think

it was likely brought to Rome by troops returning from war.

At its most deadly, the Antonine Plague

was killing a full quarter of all who became infected by it.

In the end, it is believed to have killed

roughly 60 million people.

And it wasn't just the poor and needy who suffered.

The list of the dead is believed to have included

Lucius Verus, a Roman emperor.

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From about 249 to 262 CE, the Roman Empire

was afflicted by an epidemic that eventually

came to be known as the Plague of Cyprian,

in honor of the early Christian saint

and writer who recorded the event.

Contemporary accounts suggest the symptoms included vomiting,

bloodshot eyes, loss of hearing, blindness,

and loss of coordination.

Historians don't agree on which disease was behind the plague,

but candidates include smallpox, some type of flu,

or a strain of the Ebola virus.

It is believed that the epidemic at its worst,

was killing 5,000 people a day in Rome.

In the aftermath, the empire faced

some of its most difficult years and very nearly collapsed.

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The Plague of Justinian infected the Byzantine Empire

around 541 CE and is considered one

of the first recorded pandemics.

You may want to check out some of our other videos about it.

At its peak, this plague killed roughly 10,000 people a day

and ultimately took the lives of roughly 100 million people

around the world.

While many suspected the Plague of Justinian originated

in China or India and was then spread through sea trading

routes, the particular virus or disease

that caused the pandemic was never identified.

It lasted 225 years before it finally disappeared.

And it managed to alter the course

of human political history by preventing the Byzantine Empire

from spreading into Italy.

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Smallpox is the name for a highly contagious disease that

is caused by variola virus.

Though no one knows how smallpox came into existence

or how it spread so fast, the earliest known cases

come from Egypt and India.

The oldest known evidence for smallpox

actually comes from the mummy of the Egyptian Pharaoh Ramses V.

Ramses died in 1145 BCE.

And his remains show signs of the same pockmarks

that are associated with this particular disease.

Smallpox epidemics are believed to have

killed massive numbers of people during the Middle Ages

and within the Roman Empire.

It was eventually introduced to the Western hemisphere

in the 17th century.

Brought by European explorers and settlers,

it led directly to the deaths of millions of people native

to North, South, and Central America.

It is also believed to have decimated

the populations of the Aztec and Inca civilizations.

As if all that's not frightening enough,

the Japanese smallpox epidemic, which lasted only from 735

to 737 CE, killed off approximately one-third

of the entire population of Japan.

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Malaria is an infectious disease caused

by a parasite found in mosquitoes

that infects as many as 200 million people every year.

Highly resistant to drugs, it is one

of the most consistently deadly pandemics in human history.

Spread principally through those same mosquitoes,

malaria typically impacts less developed countries.

Though scientists didn't understand it

or how it was spread until the 1800s,

this particular epidemic has been around a while.

Documented descriptions that match the symptoms of malaria

date all the way back to 2700 BCE.

Some even believe it may have been responsible

for the demise of Genghis Khan.

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Black Death is the colloquial name

for the bubonic plague, which ravaged Europe's population

throughout most of the 1300s.

It is the most notorious pandemic in human history.

And we have plenty of videos about this one.

Caused by a bacteria called "Yersinia pestis," which

is highly deadly to humans, the plague

was spread by fleas who were themselves immune to it.

The fleas would latch onto rats, who

were spread by merchant ships moving from Asia to Europe.

The Black Plague is characterized

by oozing, bleeding sores and high fevers.

During the 14th century, it is thought

to have killed somewhere in the neighborhood of 50

million people throughout Asia, Africa, and Europe.

In fact, it is believed 30% to 60%

of Europe's total population was completely wiped out.

It was also persistent.

Various forms of the plague continued

to spring up and become a recurring threat

for the next century or so.

Each time it reappeared, it claimed even more lives.

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The Cocoliztli Epidemic, also known

as the "Great Pestilence," was an incident

that occurred from 1545 to 1548 in what is today Mexico.

A mysterious illness or illnesses,

characterized by high fevers and bleeding,

swept through the Mexican highlands.

While the identity of the sickness is still unknown,

some modern researchers suspect a strain of salmonella

called "Paratyphi C" might have been the initial cause.

Today, estimates for the death toll

range from five to 15 million people,

making it the deadliest epidemic in Mexican history.

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Another outbreak of the bubonic plague, the Moscow Plague,

killed 50,000 to 100,000 people in 1770.

There is no exact figure.

But it is believed this outbreak killed about one-third

of Moscow's population at the time.

Before all was said and done, the city

experienced food shortages and intense rioting.

If there is a silver lining, it's

that after this reappearance in Moscow,

the bubonic plague essentially disappeared from Europe

in the 18th century.

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The pandemic that has come to be called the "Spanish flu"

started in 1918 and would go on to infect an entire third

of the world's population.

Estimates on the death rate vary.

But this particular sickness is believed

to have affected roughly 500 million people

and taken the lives of between 20 and 50 million people

worldwide in just two years.

Scientists would later identify the Spanish flu

as a particularly brutal flu strain called "H1N1."

The so-called Spanish flu also serves

as a warning about what can be concluded from the name

given to a pandemic.

Scientists are unsure of where in the Spanish flu originated.

France, China, and Britain have all

been suggested as a potential birthplace of the virus,

and so has the United States, where the first known case was

reported at a military base in Kansas on March 11, 1918.

So why is it called the Spanish flu?

Well, though it was one of the most ruthless pandemics

in history, it struck during World War I.

And most of its destruction wasn't

reported on at the time because of censorship.

Spain, however, was a neutral country during the war

and its newspapers were the only ones to cover the pandemic.

This led to the misnomer "Spanish flu,"

which has caused some people to falsely believe

the disease originated in Spain.

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The third pandemic was an outbreak

of the bubonic plague that originated in China

and lasted from 1855 to the 1950s.

Yes, this outbreak actually lasted almost 100 full years.

The pandemic slowly spread beyond Asia to other continents

and is believed to ultimately have taken the lives of as

many as 15 million people.

It wasn't until 1898 that Paul-Louis Simond

discovered the cause of the disease

was brown rats and rat fleas.

This discovery, the first time a scientist had conclusively

demonstrated what caused the plague,

helped curb the spread of the sickness

and eventually led to the creation of a vaccine.

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The swine flu pandemic lasted from 2009 to 2010

and is believed to have killed over 200,000 people worldwide.

Rooted in a unique influenza virus that had never previously

been identified in animals or humans,

it posed a huge problem for scientists.

The closest related flus were the North American swine, H1N1,

virus and the Eurasian swine, H1N1, virus.

But investigations quickly showed

that most of the people infected had never been exposed to pigs.

This made it clear that the new virus was only

affecting humans.

At the time, the 2009 H1N1 was considered

one of the most deadly modern pandemics

and served as a warning about how incredibly vulnerable

we humans still are to influenza strains.

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The 2014 Ebola outbreak was the largest known breakout of Ebola

in history and constituted the first actual Ebola epidemic.

This outbreak, which would last roughly two years,

would prove especially destructive to the people

of West Africa.

Finally, in March 2016, the World Health Organization

determined that the situation was under control.

Sadly, this was long after at least 28,616 cases had

been confirmed and at least 11,310 deaths

had occurred throughout Liberia, Guinea, and Sierra Leone.

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Acquired Immune Deficiency Syndrome, more widely known

by the acronym AIDS, has caused the deaths

of millions of people.

Scientists believe the disease originated in Africa

during the 1920s and spread slowly from there.

By 1981, a case had been reported

in Los Angeles, California.