Paleopathology, also spelled palaeopathology, is the study of ancient diseases. It is useful in understanding the past history of diseases, and uses this understanding to predict its course in the future.

History of paleopathology

From the Renaissance

Renaissance

The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...

 to the mid nineteenth century, there was increasing reference to ancient disease, initially within prehistoric animals although later the importance of studying the antiquity of human disease began to be emphasised. The true genesis of the field of human palaeopathology is generally considered to occur between the mid nineteenth century and World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 when a number of pioneering physicians and anthropologists, such as Marc Armand Ruffer

Marc Armand Ruffer

Sir Marc Armand Ruffer was an Anglo-German experimental pathologist and bacteriologist; he is considered a pioneer of modern paleopathology....

, clarified the medical nature of ancient skeletal pathologies. This included a review of human paleopathology published by H.U. Williams in 1929 and a book published by Pales in 1930 on paleopathology and comparative pathology. This work was consolidated between the world wars with methods such as radiology

Radiology

Radiology is a medical specialty that employs the use of imaging to both diagnose and treat disease visualized within the human body. Radiologists use an array of imaging technologies to diagnose or treat diseases...

, histology

Histology

Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...

 and serology

Serology

Serology is the scientific study of blood serum and other bodily fluids. In practice, the term usually refers to the diagnostic identification of antibodies in the serum...

 being applied more frequently, improving diagnosis and accuracy with the introduction of statistical analysis. It was at this point that palaeopathology can truly be considered to have become a scientific discipline.

After World War II palaeopathology began to be viewed in a different way: as an important tool for the understanding of past populations, and it was at this stage that the discipline began to be related to epidemiology

Epidemiology

Epidemiology is the study of health-event, health-characteristic, or health-determinant patterns in a population. It is the cornerstone method of public health research, and helps inform policy decisions and evidence-based medicine by identifying risk factors for disease and targets for preventive...

 and demography

Demography

Demography is the statistical study of human population. It can be a very general science that can be applied to any kind of dynamic human population, that is, one that changes over time or space...

.

New techniques in molecular biology

Molecular biology

Molecular biology is the branch of biology that deals with the molecular basis of biological activity. This field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry...

 also began to add new information to what was already known about ancient disease, as it became possible to retrieve DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

 from samples that were centuries old.

Human paleopathology

Human Osteopathology is classified into several general groups:

• Arthropathy
  Arthropathy
  -Scope:Arthritis is a form of arthropathy that involves inflammation of one or more joints, while the term arthropathy may be used regardless of whether there is inflammation or not.Spondylarthropathy is any form of arthropathy of the vertebral column....
  
  
• Infection
  Infection
  An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
  
  
• Oral pathology
• Trauma
  Physical trauma
  Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
  
  
• Tumor
  Tumor
  A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
  
  

Whilst traumatic injuries such as broken and malformed bones can be easy to spot, evidence of other conditions, for example infectious diseases such as tuberculosis

Tuberculosis

Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...

 and syphilis

Syphilis

Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact; however, it may also be transmitted from mother to fetus during pregnancy or at birth, resulting in congenital syphilis...

, can also be found in bones. Arthropathies, that is joint diseases such as osteoarthritis

Osteoarthritis

Osteoarthritis also known as degenerative arthritis or degenerative joint disease, is a group of mechanical abnormalities involving degradation of joints, including articular cartilage and subchondral bone. Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion...

 and gout

Gout

Gout is a medical condition usually characterized by recurrent attacks of acute inflammatory arthritis—a red, tender, hot, swollen joint. The metatarsal-phalangeal joint at the base of the big toe is the most commonly affected . However, it may also present as tophi, kidney stones, or urate...

, are also not uncommon.

The first exhaustive reference of human paleopathology evidence in skeletal tissue was published in 1976 by Ortner & Putschar. In identifying pathologies, physical anthropologists rely heavily on good archaeological documentation regarding location, age of site and other environmental factors. These provide the foundation on which further analysis is built and are required for accurate populations studies. From there, the paleopathology researcher determines a number of key biological indicators on the specimen including age and sex. These provide a foundation for further analysis of bone material and evaluation of lesions or other anomalies identified.

Archaeologists increasingly use paleopathology as an important main tool for understanding the lives of ancient peoples. For example, cranial deformation is evident in the skulls of the Maya

Maya peoples

The Maya people constitute a diverse range of the Native American people of southern Mexico and northern Central America. The overarching term "Maya" is a collective designation to include the peoples of the region who share some degree of cultural and linguistic heritage; however, the term...

, where a straight line between nose and forehead may have been preferred over an angle or slope. There is also evidence for trepanation

Trepanation

Trepanning, also known as trephination, trephining or making a burr hole, is a surgical intervention in which a hole is drilled or scraped into the human skull, exposing the dura mater in order to treat health problems related to intracranial diseases. It may also refer to any "burr" hole created...

, or drilling holes in the cranium, either singly or several times in a single individual. Partially or completely healed trepanations indicate that this procedure was often survived.

Infectious diseases in the archaeological record

Several diseases are present in the archaeological record. Through archaeological evaluation these diseases can be identified and sometimes can explain the cause of death for certain individuals. Aside from looking at sex, age, etc. of a skeleton, a paleopathologist may analyize the condition of the bones to determine what sort of diseases the individual may have. The goal of a forensic anthropologist looking at the Paleopathology of certain diseases is to determine if the disease they are researching are still present over time, with the occurrence of certain events, or if this disease still exists today and why this disease may not exist today. Some disease that are found based on changes in bone include

• Tuberculosis
  Tuberculosis
  Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...
  
  
• Leprosy
  Leprosy
  Leprosy or Hansen's disease is a chronic disease caused by the bacteria Mycobacterium leprae and Mycobacterium lepromatosis. Named after physician Gerhard Armauer Hansen, leprosy is primarily a granulomatous disease of the peripheral nerves and mucosa of the upper respiratory tract; skin lesions...
  
  
• Syphilis
  Syphilis
  Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact; however, it may also be transmitted from mother to fetus during pregnancy or at birth, resulting in congenital syphilis...
  
  

Apart from bones, molecular biology

Molecular biology

Molecular biology is the branch of biology that deals with the molecular basis of biological activity. This field overlaps with other areas of biology and chemistry, particularly genetics and biochemistry...

 has also been used as a tool of paleopathology over the last few decades, as DNA can be recovered from human remains that are hundreds of years old. Since techniques such as PCR

Polymerase chain reaction

The polymerase chain reaction is a scientific technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence....

 are highly sensitive to contamination, meticulous laboratory set-ups and protocols such as "suicide" PCR are necessary to ensure that false positive results from other materials in the laboratory do not occur.

For example, the long-held assumption that bubonic plague

Bubonic plague

Plague is a deadly infectious disease that is caused by the enterobacteria Yersinia pestis, named after the French-Swiss bacteriologist Alexandre Yersin. Primarily carried by rodents and spread to humans via fleas, the disease is notorious throughout history, due to the unrivaled scale of death...

 was the cause of the Justinian plague and the Black Death

Black Death

The Black Death was one of the most devastating pandemics in human history, peaking in Europe between 1348 and 1350. Of several competing theories, the dominant explanation for the Black Death is the plague theory, which attributes the outbreak to the bacterium Yersinia pestis. Thought to have...

 has been strongly supported by finding Yersinia pestis

Yersinia pestis

Yersinia pestis is a Gram-negative rod-shaped bacterium. It is a facultative anaerobe that can infect humans and other animals....

 DNA in mass graves; whereas another proposed cause, anthrax

Anthrax

Anthrax is an acute disease caused by the bacterium Bacillus anthracis. Most forms of the disease are lethal, and it affects both humans and other animals...

, was not found

Tuberculosis

Some diseases are difficult to evaluate in the archaeology, however, tuberculosis can be found and dates as far back as the Neolithic period. Tuberculosis is presumed to have been transmitted from domesticated cattle to humans through ingestion of contaminated meats and the drinking of contaminated milk. It is also possible to contract tuberculosis through contact with infected persons. When an infected person coughs, they eject infected mucus from their body which can possibly infect those close by. There are several types of tuberculosis, the kind that affect cold-blooded animals, the kind that affects birds and the bovine type that causes disease in humans. Because bovine tuberculosis is often found in children, it may be that the disease is spread through the consumption of contaminated milk.

Tuberculosis manifests itself in the archaeological record through DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

 extraction from the skeletal remains of people. Tuberculosis rarely manifests itself in the skeleton of individuals and when it does, it is usually only in advanced stages of the disease. The tuberculosis bacteria stays in the growth centers and spongy areas of the bone. This disease has a very long period of maturation, or the time it takes the disease to reach it's full destructive potential. Because of the long period of development in the body, tuberculosis damages the body and then the body has time to repair itself. The evidence of the disease in bones can be seen in the destruction and healing of the bone structures especially in joints. Tuberculosis therefore appears in the archaeology record in the knee and hip joints and also the spine.

It was thought that there was no tuberculosis infection in North America before the arrival of Europeans but recent findings from the 80's and 90's have overturned that idea. Through extraction of DNA

DNA

Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

 within the bone tuberculosis was not only found, but also dated to have been present in the Americas since 800 BC. Tuberculosis is a disease that thrives in dense populations. So the implications of finding tuberculosis in pre-Columbian society indicates that there was a large thriving community at the time. The earliest evidence of tuberculosis has been found in Italy dating to the 4th millennium BC. Evidence of tuberculosis has also been found in mummies from ancient Egypt

Ancient Egypt

Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...

 dating to the same period. There is however, a lack of medical texts from ancient European and Mediterranean regions describing diseases that are identifiable as Tuberculosis but the bones show that there was a disease of this type.

Syphilis

Syphilis is a disease classified in a category of Treponemal disease. This group includes diseases like pinta, yaws, endemic syphilis and venereal syphilis. These disease have symptoms that include inflammatory changes in tissues throughout the body. Initially the infected person may notice an area of inflammation at the site where the bacteria entered the body. Then the individual can expect more widespread soft tissue changes and lastly the diseases start to affect the bones. However, Only 10-20 percent of people infected with venereal syphilis show bone changes. Venereal syphilis has more severe symptoms than the other types of treponemal disease. Nervous system and circulatory disruption are unique to venereal syphilis and are not seen in yaws, endemic syphilis or pinta.

Bone changes can be seen in the archaeological record through lesions on the surface on the bone. In venereal syphilis the bone change is characterized by damage to the knees and joints. The damaged joints could be the source of infection or they could be damaged because of disruption in the nervous systems and ability to feel. In the beginning stages of the disease, the bone forms small lesions on the skull and tibiae. These lesions are caused mostly by inflammation of the marrow. In the final stages of the disease the bones start to be destroyed. Lesions that are formed tend to look similar to "worm holes" in the bone and are seen in the skull as well as large bones in the body. Most of the bone that is destroyed is due to secondary infections.

Syphilis has been seen in the Americas and Europe alike but there is debate as to what the origin of the disease is. Columbus and his sailors were said to have brought it to the Americas, however, Europeans blame Columbus for bringing the disease to Europe. There have not been any evidence of bone lesions associated with the disease that Columbus and the Europeans describe. The debate on the origins of venereal syphilis has been the subject of scientific discussions for hundreds of year and has recently been discussed and debated. At the first International Congress on the Evolution and Paleoepidemiology the subject was examined and debated by scholars from all over the world. There was no conclusive decision made as to the origin of venereal syphilis. There is however, more archaeological evidence for the disease in the Americas than there is for the disease in Europe at the time of Columbus's expeditions.

Animal paleopathology

In archaeology

Archaeology

Archaeology, or archeology , is the study of human society, primarily through the recovery and analysis of the material culture and environmental data that they have left behind, which includes artifacts, architecture, biofacts and cultural landscapes...

, the study of the diseases of animals has not been as wide and extensive as those of humans. Baker and Brothwell’s seminal work was published in 1980 and is still considered a classic text, being frequently referred to within the discipline. However, this position of importance has largely come about, not because of its comprehensive coverage, but because there has been no real alternative. Most palaeopathological literature is to be found in periodicals or compiled publications of conference papers. No synthesis of the research in the field as a whole has been attempted for the last twenty-five years. The study of dinosaur paleopathology has undergone a resurgence in the past two decades. An extensive bibliography of dinosaur paleopathology was released in 2002

External links

• Animal Palaeopathology Working Group (ICAZ)
• Paleopathology Association
• Samples of paleopathology publications
• A French site devoted to pathography, i.e. paleopathology of famous historical figures
• Paleopatologia.it - Official website of the University of Pisa, Italy. Directed by Gino Fornaciari
• The International Journal of Dental Anthropology - IJDA
• The Journal of Paleopathology