The 8 Deadliest And Most Gruesome Epidemics In Human History

Disease has been with us since the very beginning, and it's shaped our lives in more ways than we can imagine. To illustrate just how fateful they’ve been, here are the 8 deadliest epidemics in human history.

Humanity, and pretty much all living organisms, are fatefully vulnerable to disease. Viral and bacterial infections have been with us since way before our cave-dwelling days ever began, and are poised to remain among us for the foreseeable future. Much of our history is defined by disease and epidemics (especially before modern medicine), and for good reason. They shape our social and political contexts, they don’t discriminate (killing king and pawn alike), and we’re often at their mercy.

There are diseases, like malaria, that have been around for thousands of years and have killed hundreds of millions of humans throughout history. But these extended, ever-present ailments are not exactly what we think about when it comes to epidemics. Rather, an epidemic outbreak involves a contagious disease or group of diseases killing thousands of people (or more) in a relatively short period. With that definition in mind, here are the 8 deadliest and most gruesome epidemics in human history.


The Antonine Plague

Back in the first century AD, at the height of the Roman Empire, some unassuming Roman troops returned home from a siege in Seleucia (modern-day Iraq), in the winter of 165. Ignorant of what they had brought back with them, the soldiers exposed the whole Roman world to an unknown assailant (now suspected to have been either smallpox or measles). Soon enough, a quarter of the population was dead. Emperor Lucius Vernus, who reigned alongside Marcus Aurelius Antonius (for whom the epidemic was named) is reported to have been among the 5 million victims. At one point, the plague claimed more than 2,000 lives per day in Rome.

The angel of death striking a door during the plague of Rome, by Levasseur.


Plague of Justinian

One of the deadliest outbreaks on this list, the 6th-century Plague of Justinian was a catastrophe for Europe at the time, and it shaped much of subsequent European history. An instance of the bubonic plague, and afflicting mostly the Byzantine Empire, this plague claimed up to 50 million lives overall, around 13% to 26% of the world’s population at the time. Emperor Justinian I himself, for whom the event was named, contracted the disease—and although he survived, most people around him didn’t.

The Black Death

One of the most famous epidemics of all, the Black Death truly lives up to its somber name. It killed anywhere between 75 million to 200 million people across Europe, more than half its inhabitants, in a span of just four years—and fundamentally altered the medieval perception of death and punishment. As the second instance of the bubonic plague, the Black Death reduced the world’s population from around 450 million to roughly less than 350 million, which took more than 200 years to recover. Otherwise known ominously as simply The Plague, it's one of the most momentous events in human history; one that forever changed the social, political and economic landscape of Western civilization.


Cocolitzli Epidemic

Cocolitzli is a Nahuatl umbrella term, meaning “pest,” that refers to a series of diseases that decimated the native Mesoamerican population after the Spanish conquest in the age of colonization. The European invaders brought bacteria to the Americas for which the natives had no developed resistances, making them particularly vulnerable to violent outbreaks. Symptoms for these ailments included vertigo, high fever, severe headaches, black tongue, dark urine, excruciating abdominal and chest pains, and bleeding from nose, eyes, and mouth, killing people in as little as 3 days. Overall, it’s estimated that Cocolitzli killed as little as 15 million people in Mexico, with smallpox killing another 8 million.

The Third Plague Pandemic

The third major instance of the bubonic plague began in Yunnan province, China, in 1855. It spread all the way to India, killing at least 12 million people in the process. The World Health Organization declared this pandemic remained active well into the 20th century.


The Spanish Flu

This one’s not only one of the worst epidemics the world has ever known. It’s one of the deadliest natural disasters in human history, period. This exceedingly violent influenza pandemic is estimated to have infected more than 500 million people across the world, killing over 100 million—about five percent of the world’s population at the time). It was the first major pandemic related to the H1N1 influenza virus (the second being the far less lethal 2009 outbreak), and by far the most widespread. Its colloquial name (Spanish Flu) can actually be misleading. Most affected countries minimized reports of the disease in order to avoid panic, except for Spain, giving the impression the Iberian nation had been particularly devastated—or even that the disease may have come from there. In fact, no one knows exactly where the plague originated, but there’s no reason to think Spain was the culprit.

The Asian Flu Pandemic

Speaking of flu pandemics, here’s another one. The 1957 Asian Flu Pandemic was caused by the H3N2 virus (avian influenza), and led to the death of up to 4 million people across the world. It all begun in China when a mutation of the avian-exclusive virus in wild ducks freakishly mixed with a pre-existing strain that affected humans, thus creating a perfect storm.


HIV/Aids global pandemic

The human immunodeficiency virus, better known as HIV, is a particularly nasty disease that can cause acquired immunodeficiency syndrome (AIDS) over time, leading to death if left untreated. Ever since it originated in Cameroon, its worldwide spread and death toll has rendered it one of the deadliest pandemics in history, depriving humans of their immune system and allowing other simple infections and even cancers to thrive. The virus has infected over 60 million people and killed more than 25 million of them. Though the pandemic is still ongoing, at least today the infection is treatable, and the medical community is making progress towards finding a cure.

Your voice matters!
Are you a history or medical expert? Do you want to be heard? Read our submissions guidelines and send us a 500-word article to for a chance to share your thoughts with the rest of the world!

Check out these other articles!
The Weirdest Things To Keep In Mind If You Time-Traveled To Medieval England
10 Brutal Facts About World War 2 You Probably Didn't Know
The Bloody Viking Torture Method That Shaped Ribs To Look Like Wings

Podría interesarte