Diseases are an interesting thing. The development and location of an area can drastically change the types of diseases present, and which are most deadly. If you look at global health maps, such as HealthMap, you can see how drastically different outbreaks are occurring in different areas. For example, cholera has been a major concern in different places as development of them has occurred. It is an infection of the intestine caused by bacteria, and is transmitted through water that has been contaminated by infected human feces. It was a major health threat in English cities during the mid-19th century, but now it is rarely found in first world countries. Today, cholera continues to plague third world countries, and is especially prevalent in Africa, though the most recent epidemic occurred in 2010 in Haiti. The difference is the ability to gain access to clean water- whether that means rural areas where water hasn’t been contaminated or processed and cleaned water from modern cities. Due to place and development having such an effect on the health of the local population and the types of diseases, we can use paleopathology, the study of disease in human remains, to learn more about major changes in human history.
One of the largest developments mankind has faced is the change from a hunter-gatherer mobile groups to agricultural sedentary communities. A new article from the Journal of Osteoarchaeology by Mosher, Smith, Albrecht and Salaka (2013), discusses the changes in paleopathology associated with the switch to maize agriculture and village settlements in West Central Illinois from 1050 to 1300 CE. While the period overall saw major changes, the way that this was experienced and the pace of development was highly varied throughout this region due to differences in culture, the ecological contexts of the river bottom versus upland communities, and their differential interactions with Cahokia, the largest settlement north of Mexico. In order to understand how this development affected a specific population from a remote hinterland area of the Upper Mississippi River, the prevalence of treponemal disease and tuberculosis were examined in the skeletal population. Prior studies have linked the rise of these two diseases as consistent with increased sedentism (not mobile, but living in the same place over long periods of time) which challenges previous inferences that this region was occupied by foraging mobile horticulturalists in this period.
First, a little introduction to treponemal disease and tuberculosis. Nonvenereal treponemal disease (including yaws and treponarid, not syphilis) is a chronic disease that is transmitted by Treponema spirochetes invading the skin. It is most commonly contracted during childhood and is found associated with poor hygiene. The tertiary stage of the disease affects the bones, most commonly appearing as star like lesions on the cranium. There is a correlation between the rise of villages and increased treponemal disease. Tuberculosis (TB) is a pulmonary disease that affects human bone, and is associated with living in aggregated communities like villages. In human remains it is most commonly interpreted from anterior vertebral kyphosis, when the vertebral bodies collapse, and is seen more frequently following increased maize production in 900 CE in North America.
In order to determine how sedentary and agricultural the community was from Schroeder Mounds, Mosher et al. (2013) examine the skeletal remains from the site that date from 900–1100 CE. The adult skeletal sample includes 53 individuals. 18 individuals show some type of reactive bone growth indicative of non-specific disease or trauma. Of these, 7 display the star-like lesions or other types of indicators commonly associated with treponemal disease such as nodular lesions. Of those 7, 3 have signs of traumatic injury that may have led to the initial infection. 4 other individuals have plausible signs of treponemal disease, but cannot be completely diagnosed based on the available evidence. There were no individuals who had signs the diagnostic signs of tuberculosis, although 3 had plausible cases based on lesions on the ribs ends.
The goal of this analysis was to solve the question of how mobile or sedentary this group was using paleopathology as evidence. There is a lack of other archaeological evidence such as ceramics have prevented full conclusions about this area to be determined. Mosher et al. (2013) argue that the presence of tertiary stage treponemal disease confirms that this group was sedentary, which is a common pattern for the broader region and time period that had not been determined locally. This is not a final conclusion, but rather a starting point from which future archaeological evidence can be interpreted.
G. M. MOSHER, M. O. SMITH, J. L. ALBRECHT, & V. P. SALAKA (2013). Treponemal Disease, Tuberculosis and Subsistence-settlement Pattern in the Late Woodland Period West-central Illinois International Journal of Osteoarchaeology DOI: 10.1002/oa.2344