A multi-institution interdisciplinary research team investigated the conditions surrounding the death of a 23-year-old Black male who died in the 1930s with the goal of better understanding the social systems that influenced his health and well-being during his life in early 20th century St. Louis, Missouri. The researchers refer to him as St. Louis Individual, or St. LI, to protect his identity. Their study, “Remembering St. Louis Individual—structural violence and acute bacterial infections in a historical anatomical collection,” was recently published in Communications Biology.
“It’s extremely rare that researchers can identify exactly what killed people in the past, or their cause of death, but the bacterial DNA in St. LI’s calculus precisely matches their recorded cause of death of pneumonia,” said Molly Zuckerman, study coauthor and professor in the Department of Anthropology and Middle Eastern Cultures at Mississippi State University. “This means that dental calculus, or calcified human dental plaque, which dentists scrape off the teeth of the living, can give us an otherwise impossible window into what killed many people in the past and shed light into the end of their lives. This is especially true for many who were historically marginalized, such as those shuttered in institutions, like asylums and public hospitals, and whose end-of-life experiences have largely been lost to history.”
When examining his dental calculus, researchers found bacteria that commonly caused pneumonia and hospital infections before antibiotics became widespread in the 1940s. Pneumonia was one of the most common causes of death amongst humans in the past, especially for the poor, older adults and other marginalized communities living in crowded and cramped cities from the medieval period into the Industrial Revolution. However, pneumonia does not leave marks on the skeleton and was often not well diagnosed by doctors and other medical professionals into the early 1900s.
Rita Austin, the first author of the study and currently a postdoctoral researcher at the University of Oslo in Norway, said, “Combining information from DNA preserved within dental calculus on St. LI’s teeth with historical documents that contextualize their life, and information about their overall health and well-being gleaned from their skeleton, has given us an extraordinary look into how racism, poverty and violence in 1930s St. Louis shaped this person’s life.”
Even in the 1930s, pneumonia was not typically fatal for young adults. But St. LI’s skeleton shows that he was in extremely poor health, especially for his age, and may have been immunosuppressed, leaving him vulnerable to the infection. Specifically, his skeleton shows traces of having experienced trauma, including a poorly healed jaw fracture, which study author Geoff Ward says is “indicative of an exposure to violence and other harm, and inadequate health care, throughout his short lifetime,” noting the “widespread political violence, occupational hazards, and interpersonal conflicts in the period and places where his life unfolded.”
The research team said that St. LI was also probably infected with tuberculosis. Study coauthor Hedwig Lee said TB “was common in the crowded, poor-quality housing Black and African Americans experienced in St. Louis and other cities in the late 19th and early 20th century, such as Philadelphia, as evidenced in research conducted by W.E.B. DuBois during this time period.”