What is the earliest known disease? Exploring the origins of ancient human illness

September 23, 2025 •

4 min read

While infectious diseases like smallpox and influenza have plagued humanity for centuries, modern research into paleopathology and ancient DNA reveals that other conditions, such as cancer and tuberculosis, have a far longer history. Recent studies on hominin fossils have provided surprising evidence for what is the earliest known disease.

Quick Summary

Cancer is arguably the earliest known disease, with fossil evidence showing a malignant tumor in a hominin bone dating back 1.7 million years, though older infectious diseases like tuberculosis are also contenders based on ancient DNA analysis.

Key Points

Cancer is incredibly ancient: Fossil evidence reveals a 1.7-million-year-old malignant tumor in a hominin bone, making it a strong contender for the earliest known disease.
Tuberculosis evolved alongside humans: Genetic analysis suggests the bacterium causing TB has co-evolved with hominids for at least 70,000 years, becoming more virulent with the rise of larger human settlements.
Shift to agriculture created new diseases: The Neolithic period, with its dense populations and close contact with domesticated animals, facilitated the emergence and spread of infectious diseases like measles and plague.
Paleopathology and ancient DNA are key: New scientific methods, including 3D imaging of fossils and DNA extraction from ancient remains, are revolutionizing our understanding of ancient illnesses like malaria and leprosy.
Defining 'earliest' is complex: The answer depends on whether one considers the earliest evidence of a disease process (like cancer) or the oldest infectious pathogen identified in human history.

Uncovering the Deep Roots of Human Illness

For centuries, the search for the earliest known diseases relied on ancient texts and visible damage on mummified or skeletal remains. This approach yielded valuable information about infectious scourges and other ailments that plagued ancient civilizations. However, breakthroughs in modern paleopathology and ancient DNA analysis have pushed the timeline of human disease back significantly, revealing illnesses that afflicted our ancestors long before written history began. The question of which is truly the earliest depends on the evidence available and how one defines a 'disease'. By examining evidence from hominin fossils, ancient DNA, and written records, a clearer, though still debated, picture emerges.

The Strongest Contender: Early Evidence of Cancer

Perhaps the most surprising candidate for the earliest known disease is cancer. In 2016, a study on a 1.7-million-year-old toe bone from a hominin found in South Africa's Swartkrans Cave reported the world's oldest known human malignant tumor. Advanced 3D imaging confirmed the diagnosis as osteosarcoma, a type of bone cancer. An even older discovery from the same site revealed a benign tumor, an osteoid osteoma, on the vertebra of a 1.98-million-year-old Australopithecus sediba. These findings demonstrate that cancer, a disease often associated with modern lifestyles, has deep evolutionary roots and is not simply a product of contemporary living conditions.

The Discovery and Analysis

Finding: A 1.7-million-year-old hominin toe bone with evidence of a malignant tumor was discovered in South Africa.
Method: Researchers used advanced 3D imaging for high-resolution analysis without damaging the fossil.
Confirmation: Analysis revealed patterns consistent with osteosarcoma.
Significance: This challenged the view of cancer as a modern disease.

Tuberculosis: An Ancient Infectious Foe

While cancer holds the record based on skeletal evidence, tuberculosis (TB) offers a compelling case for the oldest infectious disease affecting humans. Genetic studies of the Mycobacterium tuberculosis complex have shown that the organism has been co-evolving with hominids for at least 70,000 years. Skeletal remains from a Neolithic settlement dating to 9,000 years ago show characteristic bone lesions and contain DNA evidence confirming TB infection.

The Evolution of Tuberculosis

Early Co-evolution: Ancestral strains likely emerged over 70,000 years ago, initially relatively mild.
Population Growth and Spread: Larger communities in the Neolithic period facilitated the spread and increased virulence of the bacteria.
Human vs. Animal Transmission: Ancient DNA evidence suggests humans may have passed TB to animals rather than the reverse.
Archaeological Evidence: TB evidence is found globally in ancient remains, including Egyptian and Peruvian mummies.

Other Ancient Ailments

Beyond cancer and tuberculosis, paleopathology reveals other ancient conditions.

Dental Caries: Evidence dates back at least 15,000 years, becoming more common with agrarian diets.
Malaria: Genetic analysis shows malaria parasites dating back 5,500 years, likely spreading with agricultural practices creating mosquito breeding grounds.
Leishmaniasis: Identified in mummies from at least 4,000 years ago, with pathogens likely millions of years old.
Plague: DNA of Yersinia pestis found in Bronze Age remains (3,800 to 5,000 years ago), possibly contributing to population declines.

What Makes a Disease 'Earliest'? A Comparative Look

Identifying the "earliest" disease is complex due to varying evidence types and timelines. Here is a comparison:


Feature	Evidence for Cancer	Evidence for Tuberculosis	Evidence for Plague	Evidence for Malaria
Type of Evidence	Malignant and benign tumors on fossilized bone	DNA analysis, characteristic bone lesions in skeletons and mummies	DNA analysis from teeth of ancient humans	Genetic material from ancient human remains
Earliest Confirmed Date	1.7 million years ago (malignant)	At least 70,000 years ago (molecular), 9,000 years ago (skeletal)	3,800 to 5,000 years ago (ancient DNA)	5,500 years ago (ancient DNA)
Infectious vs. Non-infectious	Non-infectious	Infectious	Infectious	Infectious
Discovery Method	3D imaging of physical fossil	Ancient DNA extraction and skeletal analysis	Ancient DNA extraction from teeth	Genetic analysis of tissue samples

The Intersection of Environment, Lifestyle, and Disease

Ancient diseases are linked to human evolution and societal shifts. The transition to settled agriculture during the Neolithic Revolution led to increased population density and proximity to domesticated animals, creating opportunities for infectious pathogens to spread and jump species. Measles and smallpox, for instance, likely evolved from animal viruses and thrived in larger agrarian populations.

Conclusion: A Complex and Evolving Answer

So, what is the earliest known disease? While cancer has strong evidence from a 1.7-million-year-old fossil as the earliest physical manifestation of disease in a hominin, tuberculosis, with a co-evolutionary history potentially stretching back 70,000 years, represents an equally ancient infectious threat. Paleopathology continues to reveal the deep history of disease as an ancient part of the human story.

For more in-depth information, consider visiting the National Institutes of Health website for authoritative research on historical and modern health issues.

Frequently Asked Questions

Scientists use a field called paleopathology, which studies diseases in ancient human and animal remains. Techniques include examining fossilized bones for abnormalities like tumors or lesions and extracting ancient DNA from bone or teeth to identify specific pathogens like bacteria or parasites.

While often associated with modern environmental and lifestyle factors, cancer is an ancient disease. The discovery of a 1.7-million-year-old malignant tumor in a hominin fossil and a 1.98-million-year-old benign tumor provides clear evidence that cancer existed in early human ancestors long before modern times.

Infectious diseases existed before large communities, but many became more prevalent and endemic due to the increased population density and proximity to domesticated animals that came with the agricultural revolution around 12,000 years ago. Some pathogens, like herpes viruses, have been with our ancestors for millions of years.

Tuberculosis is one of the oldest infectious diseases, with genetic evidence suggesting its origin dates back at least 70,000 years, co-evolving with early humans. Characteristic bone lesions and ancient DNA confirm its presence in Neolithic communities as far back as 9,000 years ago.

The existence of malaria in ancient times is supported by genetic material from the parasites that cause it. Recent research has identified malaria DNA in ancient human remains dating back 5,500 years, showing its long history as a human pathogen.

The transition from hunting and gathering to settled agriculture drastically altered disease patterns. Denser, less mobile populations provided ideal conditions for epidemic diseases to spread, while dietary changes contributed to conditions like dental caries. Close contact with domesticated animals also introduced new pathogens.

Pinpointing the first human disease is challenging because much of the evidence relies on preserved remains. Soft tissue diseases leave little trace, and early non-infectious conditions may not be recorded. The definition of a 'disease' can also be debated, adding complexity to the historical record.