Studying Past Plagues: Paleopathology & Evidence

How to Study Past Plagues

• Ancient hunter-gatherer groups did not experience infectious diseases commonly seen in modern times due to their small size, isolation, and mobility
• Historians, archaeologists, biologists, and geneticists use various sources to study past plagues, each with its own limitations

Paleopathology

• The science of interpreting evidence of disease in ancient human remains
• Encompasses all parts of the body: bones, teeth, soft tissue, hair etc.
• Aims to describe and analyze standard observations on remains to create a differential diagnosis, ideally arriving at a single most likely diagnosis
• Direct evidence comes from human remains, while indirect evidence includes coprolites, soil, and animal remains
• Focus has shifted from individual cases to populations

Direct Evidence Examples

• Mummies have soft tissues preserved, sometimes including skin and internal organs
• Skeletal and dental remains are sources of evidence

Mummies

• Relatively rare, they can be deliberate or accidental
• Require hot and dry, cold and dry, or anaerobic conditions for preservation
• Distribution of sites skews our understanding of past health

Tollund Man

• A "bog body" found in a Danish peat bog
• Underwent natural mummification

Ötzi the Iceman

• A 5000-year-old mummified man
• Had tattoos located where he had osteoarthritis

Studying Bones and Teeth

• Bones and teeth preserve better than soft tissue
• Paleopathologists look for abnormalities in shape, size, bone formation, bone loss, fractures, dislocations, arthritis, developmental issues, and genetic diseases
• It is slow, taking time for bone lesions to develop
• Bone has two reactions: growth and resorption, making it hard to distinguish diseases

Bone Provenance

• Scientific archaeological excavations of cemeteries, villages, houses, and ceremonial places
• Salvage archaeology during building roads, buildings, and pipelines
• Erosion
• Graverobbing

Diseases

• Syphilis, caused by Treponema pallidum, leads to a worm-eaten appearance of the skull and saber shins
• Tuberculosis results in Pott's Disease = collapses the spine.
• Hansen's Disease aka Leprosy is caused by Mycobacterium leprae and is hard to identify

Dental Pathology

• Useful to tell about disease, diet, age etc
• Dental caries or cavities can leave a mark forever

Paleoparasitology

• Examines parasites in ancient material
• Useful because eggs preserve but worms degrade

Coprolites

• Preserved feces found in ancient bathrooms or near stomach areas within burials
• Preserves parasites and eggs

Body Lice/Fleas

• Can be found on mummies, clothing, and in living spaces
• Preserved eggs are primarily what can be found

Ancient DNA (aDNA)

• Isolates from ancient specimens
• It can be very objective and very sure if get results

Analysis

• Demographic history, phylogeny, selection signatures
• Taxonomy analysis and microbial profiling
• Damage pattern analysis
• Genome reference analysis

Caveats of aDNA

• Destructive to bones and tissues
• Very expensive
• Often fails
• It is unreplaceable especially in old bodies

Art

• Art can depict disease but with interpretive bias

Historical Records

• Include chronicles, letters, diaries, newspapers, and parish records
• Definitely biased because only literate people could produce them

Death Certificates

• Give an idea of mortality

Explore the study of past plagues through paleopathology, which focuses on interpreting evidence of disease in ancient human remains. Direct and indirect evidence, including mummies and skeletal remains, provide insights into the diseases that affected past populations. The focus has shifted from individual cases to populations.