Leading from the Middle: Using the Medieval Scourges of Leprosy and Plague to Frame a Deep Global History of Health

Monica H. Green
Professor of History, Arizona State University
Thursday, November 21, 2013 – 4:30 pm
Van Dyck Hall, Room 301
16 Seminary Place New Brunswick, NJ 08901
Reception to follow

Historians of the Middle Ages have been in an unusual situation the past few years:  they have watched as their field has become hot!  The medieval scourge of plague (Yersinia pestis) was the first pathogen to be fully sequenced from ancient remains.  And now a type of leprosy (Mycobacterium leprae) has become the first pathogen to be fully sequenced entirely without a modern reference sequence. The science itself is absolutely
cutting-edge, and most historians who can understand it are in awe of its sophistication and implications for the reconstruction of two major diseases that still afflict far more people than they should in the modern world. Yet historians themselves have been sidelined in most popular news accounts, often breathless in their excitement, of the latest discovery of a plague pit or leprosarium excavated.  Likewise, not a single one of the major studies on plague or leprosy has included a historian on its research team.  Nor, it seems, has a historian ever been asked to do peer review of a biomolecular or paleopathological study published in a science journal.

What are the consequences of the omission of historians from this new writing of disease history?  This paper will argue that historians are not simply useful but vital, since there is no substitute for incorporating rigorously assessed information about human (rather than pathogen) actions into our narratives about the history of disease.  A recent news account about the latest paleogenetics study on leprosy, for example, trotted out
the old canard about leprosy having been spread because of the Crusades. Wars are certainly attractive suspects for the spread of infectious diseases, of course, but neither the chronology nor the epidemiology of
this slow-moving disease fits this theory well enough for it to be taken seriously when setting research agendas for the future.  (Trade, and particularly the slave trade, is a far more likely culprit for the long-distance spread of different strains.)

The notion of “consilience” between different disciplinary results has increasingly been used among climate historians, and it can usefully be applied to disease history, too.  Genetics now can tell us, in broad form, how diseases become global.  But it will be historians that will likely prove critical in reconstructing the finely-grained picture that will give us epidemiologically meaningful information on why, for example, leprosy was able to spread out from Europe to the New World at precisely the time it was contracting in its old home. The fact that plague and leprosy can now be studied in great detail from both material and cultural records from medieval Eurasia gives us, I believe, a formula that can be applied to other diseases and other times and places.   Tuberculosis, malaria, smallpox, syphilis, cholera, and HIV/AIDS all are global diseases that can be studied from the same interdisciplinary perspective that combines genetics, paleopathology, and historical analysis of cultural products.  This synthetic approach can be stretched back to pre-history but also adapted for those historical contexts where we have far more meager remains than we do for medieval Eurasia. The Middle Ages thus become central to a project of constructing a truly global history of health.

Co-sponsored by GAIA, the Department of History, Rutgers-Newark, the Program in Medieval Studies, the Medical Humanities Working Group, and the Center for Cultural Analysis.