10 Most Ancient Diseases Known to Humans

Key Insights

When examining ancient diseases, the dead have the most to tell us.

"Bone deformities are a key indicator," said Dr. Anne Grauer, anthropologist at Loyola University Chicago and president of the Paleopathology Association, in an exclusive interview. The evidence of tuberculosis is particularly easy to trace because of the damage it inflicts on bones. Pneumonia, while likely older than TB, is harder to track as lung tissue decays too quickly in the ground.

"Genomic data also serves as a valuable tool in dating diseases," explained Dr. Charlotte Roberts, archaeologist at the University of Durham and author of the book "The Archaeology of Disease." DNA tests conducted on mummies and skeletal remains can confirm the presence of specific diseases. Even without intact bodies, the genetic markers found in modern samples of TB and leprosy bacteria suggest their origins date back to prehistoric times.

Determining the oldest known diseases may be tricky, largely due to the very definition of "disease." This article will focus solely on human, infectious, viral, or bacterial ailments. So, conditions such as tooth decay, psoriasis, gout, obesity, rickets, epilepsy, arthritis, and other human afflictions are excluded from this study, as they might better be categorized as "conditions" rather than true diseases.

Curiously missing from the list of ancient diseases are some of the deadliest in history, including influenza, measles, and the black plague. These illnesses are typically associated with large population densities, a phenomenon that only emerged as humans began forming cities. Influenza, measles, and the plague spread within social communities, while malaria does not.

We have compiled a list of 10 of the oldest known diseases, presented in no particular order. On the next page, we'll begin by exploring a condition that thrives in crowded environments.

10: Cholera

In around 400 B.C.E., the Athenian physician Hippocrates documented the diseases of his time. Cholera was included in his catalog. While Hippocrates provides the first solid proof of cholera, the disease likely originated along the Ganges River while Athens was still a young city.

Cholera is found in many of the world's water sources, but it is particularly dangerous in areas with dense populations. The Ganges River, being one of the earliest places with such population density, became a hotspot for cholera. As more people became infected, they contaminated the water supply, which in turn spread the bacteria to even more individuals.

Interestingly, the same issue may have been a significant reason for the loss of soldiers during Hannibal's journey over the Alps. With an army of 50,000, the troops and animals at the front would have had access to clear mountain streams, while those at the back would have been forced to drink contaminated, possibly cholera-laden water [source: Hunt].

9: Typhoid

From 430 to 426 B.C.E., a devastating plague struck Athens. The historian Thucydides captured the symptoms as follows:

The timing of the disease couldn't have been worse. The plague played a crucial role in Athens' eventual defeat by Sparta in the Peloponnesian War, marking a prolonged setback for democracy in world history.

What caused this devastating plague?

8: Leprosy

The Bible verse Leviticus 13:2 states, "When a man shall have in the skin of his flesh a rising, a scab, or bright spot, and it be in the skin of his flesh like the plague of leprosy; then he shall be brought unto Aaron the priest, or unto one of his sons the priests."

However, this isn't the earliest documented reference to the disease. The Egyptian "Ebers Papyrus," written in 1550 B.C.E., takes that distinction. It advises: "If you examine a large tumor of Khonsu in any part of a man and it is terrible and it has made many swellings. Something has appeared in it like that in which there is air ... Then you shall say concerning it: It is a swelling of Khonsu. You should not do anything against it" [source: Nunn].

While typhoid and cholera spread aggressively through contaminated water, leprosy uses a different method: dormancy. People can carry the bacteria responsible for leprosy for over 20 years without showing symptoms, and during this silent period, they can unknowingly transmit the disease.

One of the challenges in treating leprosy throughout history was its diagnosis. In its early stages, leprosy can resemble conditions such as syphilis or even psoriasis. This led to misdiagnoses, and many individuals diagnosed with psoriasis were sent to leper colonies, where, ironically, they often contracted and died from leprosy due to increased exposure.

7: Smallpox

The main purpose of mummification is to preserve the soft tissues of the body. Naturally, Egypt holds an abundance of information on diseases affecting these tissues in ancient times.

Sir Marc Armand Ruffer was one of the first researchers to apply a paleopathological approach to Egyptian mummies. In his 1921 work "Studies of the Palaeopathology of Egypt," he identified three mummies with "dome-shaped vesicles," which closely resembled those seen in smallpox [source: Ruffer]. The oldest of these mummies was from 1580 B.C.E., while the most recent was that of Ramses V, who died in 1157 B.C.E.

Upon inspecting the mummy himself, Donald R. Hopkins, a key figure in the World Health Organization's Smallpox Eradication Program, reported that Ramses V's remains showed "a rash of elevated 'pustules,' each about 2 to 4 millimeters in diameter, most pronounced on the lower face, neck, and shoulders, with some visible on the arms." [source: Hopkins]

Is this evidence conclusive? Not entirely, as no modern analysis of Ramses V's mummy has definitively confirmed whether he had smallpox. Still, the circumstantial evidence remains compelling.

Smallpox stands as one of history's most lethal diseases, having caused the deaths of between 300 and 500 million people in the 20th century [source: Saint Louis University].

6: Rabies

Rabies is a clever disease: It not only infects its host, but also manipulates the host's brain, driving it to bite. This behavior is what allows rabies to spread. This has been happening since at least 2300 B.C.E., when it was mentioned in the Eshuma Code of Babylon [source: Rupprecht et al.].

The first known survivor of rabies without receiving a vaccination was Jeanna Giese, a Wisconsin teenager who was bitten by a rabid bat in 2004 while attending church. According to The New York Times, Jeanna went an entire month between the bite and receiving treatment. She was hospitalized with full-blown symptoms of rabies [source: Rosenthal]. At Children's Hospital of Wisconsin, doctors began a regimen of coma-inducing and antiviral drugs, although Giese's family believes prayer played a significant role in her recovery.

5: Malaria

The Romans were the first to propose a remedy for malaria: an amulet to be worn around the neck, inscribed with the potent charm "abracadabra" [source: Shah]. Over time, we've explored various treatments: pouring oil on stagnant water to suffocate mosquito larvae, using pesticides, vaccines, and nets, and even employing advanced technologies like lasers that target mosquitoes mid-flight. However, malaria continues to affect 300 million people annually, claiming the lives of 1 million [source: Shah].

According to The Wall Street Journal, malaria is responsible for half of all human fatalities since the Stone Age [source: Shah].

Admittedly, this statistic stretches the disease's origins beyond its first recorded mention, which appears in the Chinese text "Nei Ching" ("The Canon of Medicine"), around 2700 B.C.E. [source: CDC].

4: Pneumonia

Every day, people inhale more than 11,000 liters (3,000 gallons) of air [source: Nebraska Department of Environmental Quality]. As a result, the lungs become a prime target for bacteria, viruses, fungi, and even parasites. When any of these foreign invaders settle in the lungs, the body typically responds by producing fluid. This accumulation of fluid in the lungs is what we call pneumonia.

Hippocrates defined pneumonia as fluid in the lungs, stating it should be called so if, "the fever be acute, and if there be pains on either side, or in both, and if expiration be if cough be present, and the sputa expectorated be of a blond or livid color" [source: Hippocrates]. He also noted that it was a "disease of the ancients."

How does pneumonia rank among the oldest known diseases? As a soft tissue affliction, its presence in the archaeological record is limited. However, it's probable that various types of pneumonia have existed as long as humans have had lungs.

3: Tuberculosis

In 2008, researchers from University College London uncovered the submerged ancient city of Alit-Yam, located off the coast of Israel. Among their discoveries were the remains of a mother and child, both showing bone lesions typical of tuberculosis [source: Lloyd]. DNA analysis confirmed that tuberculosis is at least 9,000 years old.

Interestingly, this excavation also contributed to the ongoing debate of whether tuberculosis was transmitted from cows to humans or vice versa. While human skeletons displayed signs of TB, no TB DNA was found in animal remains at the site [source: Hershkovitz et al.]. This suggests cows are not the original source as once suspected.

Other historical theories have also been debunked: Neither fossil nor DNA records support the notion that TB was caused by late-night feasts with fairies and sleep deprivation, nor is there any evidence that the disease came from witches turning victims into horses for nocturnal gatherings, as had once been believed [source: Briggs].

While the discovery at Alit-Yam is the oldest confirmed case of tuberculosis, skeletal remains from Turkey, dating back about 500,000 years, also show characteristic bone lesions of the disease [source: Lloyd].

2: Trachoma

Trachoma is a long-lasting infection of the upper eyelid that causes the eyelid to shrink and pull the eyelashes toward the cornea. This persistent rubbing of the eyelashes against the cornea eventually leads to blindness. Historical figures such as Aetius, Paulus Aeginetus, Alexander, Trailaus, Horace, and Cicero are believed to have suffered from this condition. Trachoma is referenced in works by Hippocrates and the Egyptian Ebers papyrus [sources: Siniscal and Nunn].

Interestingly, researchers point to evidence of trachoma in a surprising place: Australia. Aboriginal skeletons from 8000 B.C.E. exhibit a distinct skull lesion around the eyes [source: Webb]. The lesions, caused by bone infection from a soft tissue infection, suggest trachoma. These skeletal remains were found in a region of Australia where trachoma is still prevalent today.

1: Rocky Mountain Spotted Fever

Mitochondria are small organelles found in nearly every cell in the human body. And they perform a function essential to human life, converting glucose from food to energy called adenosine triphosphate, or ATP, which cells can use.

But mitochondria carry their own genetic material -- separate from human DNA -- and these genes look a lot like those of bacteria. In other words, it's very likely that the mitochondria that we depend on for survival are the products of an ancient infection [source: Andersson et al.].

Whatever the infection, it predates animal life, let alone humans. So there's no use exploring the fossil record. Instead, researchers compared the genes of mitochondria to those of existing bacteria. The closest match was to bacteria of order Rickettsiales, many of which cause diseases -- including Rocky Mountain spotted fever [sources: Eremeeva and Dasch, Andersson et al.].

But remember, we're talking about a disease that existed before animal life. So the oldest disease isn't really Rocky Mountain Spotted Fever itself, but some unnamed proto-disease with genetic similarity.

A long time ago, bacteria made their way into a cell. This invasion led to the world as we know it today.

Continue reading on the next page for more articles about infectious diseases.