Epidemiology 101 for Medievalists—or, Why Narratives Matter in Historicizing Hate-Speech

by Monica H. Green

I. Where Are You From?

I confess. I get no small pleasure in disrupting the “Where are you from?” questions I’ve gotten all my life. When I answer “Japan,” the logical fallacy reveals itself on the face of my interlocutor. I don’t “look” Japanese and therefore the initial question, which should have allowed them to compartmentalize me according to a “continent of origin” racial logic, proves useless. Sometimes “facts” are useless.

There has been much talk this past year about “infodemics.” This is not just your garden variety “Fake News” but the circulation of factoids and narratives that do immediate harm in terms of disrupting public health initiatives and even allowing certain individuals or groups to be targeted for harassment. In the context of a pandemic, separating disease narratives from both geography and ethnicity has been crucial for the World Health Organization, which for some time has recognized the need for neutral terminology to refer to new diseases. Overall, the WHO was successful in quickly shifting public usage toward “COVID-19” and “SARS-CoV-2” early in 2020. Trump’s insistence on using geographic terminology was deliberate, aggressive, and malicious.

But here’s the problem: it was not factually wrong. To label all such information as “false” undercuts a basic moral objective that both History and epidemiology share: truth-telling. Because for both History and epidemiology, origin stories are important. They tell us something about when things happen, how things happen, and why they happen. To date, both on-the-ground and modelling studies suggest that the origin of the SARS-CoV-2 virus—its definitive transition from a virus of another animal host to one of humans—happened not too long before (and possibly not too far away from) the place where the first human cases were reported in December 2019.

As medievalists, we know the power of stories. And we know all too well how stories are constructed selectively and can be used to actively harm as well as enlighten. We know how lacunae and inferences, episodic plotting and time compression, can direct attention different ways. We are in an extraordinary moment of global awareness now, the whole world having been united by a pandemic this past year. I, a specialist in medieval medicine, am one of the historians who has been arguing that our present crisis is not unique, but shares important parallels with pandemic crises humankind has faced before. A field I call “Global Health History” is coalescing as the histories of humanity’s major infectious diseases come more tightly into focus under the trifold efforts of the fields of palaeogenetics, bioarchaeology, and medical history. But as this line of investigation coalesces, so, too, should awareness of how stories shape our ways of thinking and choices in behavior.

And that is why, as medievalists, we should recognize the role we might inadvertently already be playing. We have already been made aware of the Pandora’s box of white supremacy that is openly making use of partly-true, partly-fictitious narratives about the Middle Ages. Most recently, we are seeing the rise of anti-Asian racism and violence. Both crises were fueled by the former U.S. President. But they did not come out of nowhere, and their intersections are not unrelated. We are in a position not only to be attuned to mistaken uses of the past, but to be more careful in how we ourselves connect the past to the present.

II. Not Origins, But Processes

In an essay published in the Smithsonian Magazine on 25 March, David Perry (a fellow medieval historian), described my recent work on the origin of the late medieval plague pandemic: “[Green] identifies a ‘big bang’ that created four distinct genetic lineages [of the plague bacterium] that spread separately throughout the world and finds concrete evidence that the plague was already spreading from China to central Asia in the 1200s.” Actually, Perry got the geography reversed. Amplifying and revising arguments that sinologist Robert Hymes had already laid out in 2014, I argued that plague spread from central Asia (specifically, the Inner Asian Mountain Corridor) to China in the 1200s. The error was seemingly minor, yet simply “correcting” it is not the intervention that’s needed. Whether backwards or forwards, the statement could be read by the casual reader as reinforcing beliefs that somehow Asia is inexorably associated with disease. The thing is, all human populations are associated with disease. And we need smarter thinking about that fact.

Infectious diseases infect. By definition (in our modern understanding) they are conditions caused by microscopic organisms that enter into human bodies. These microorganisms have their own evolutionary objectives of survival and replication; they are only “pathogens” because of what they do to us. Sometimes (as with SARS-CoV-2) they become “obligate”: they adapt to humans as their main or sole host and move solely from human to human. Sometimes (as with plague) they have multi-host ecologies, in which humans are an incidental stage. The point is, this process of interacting with human bodies had a beginning. Every pandemic, before it became pan-demic, was a local outbreak. And that’s where geographies of origin take their genesis.

Mapping disease is at the heart of epidemiology as a field. The so-called “father of epidemiology,” the 19th-century anesthesiologist John Snow, famously mapped a local cholera outbreak in London in 1854, gradually determining why certain individuals were exposed or not depending on their water supply. Case investigation and contact-tracing are the most common forms of “shoe-leather epidemiology,” and they have been vital for interventions in the current pandemic. How, then, do we navigate this narrow strait, between the Scylla of needing, as historians and epidemiologists, to track the forces that transform a random spillover event into epidemics and pandemics, and the Charybdis of weaponized epidemic geographies? How we navigate it, I propose, is by following the WHO and all epidemiologists in fundamentally separating the necessary investigation into causes from any assignation of blame.

And that is for several reasons, first and foremost because all spillover events (and there have no doubt been many thousands more than we will ever know about) are accidents. “[D]ocumenting humans doing what humans do” was how I phrased the epidemiological historian’s task in my 2020 essay. Seeking sources of food, or fuel, or “fun” is what humans do. All of us. And it is in the course of pursuing those human pursuits that a bug—a bacterium, a virus, a microparasite—that has not previously taken up its home in human bodies makes the leap. What happens after that leap determines whether that bug initiates a pandemic.

In a tweet announcing his article in the Smithsonian, Perry wrote: “In the midst of a global pandemic, the stakes for understanding how pandemics happen couldn’t be higher.” How pandemics happen, not “where they come from.” That is indeed the question. How the late medieval plague pandemic happened is a rather mundane story of grain supplies. I proposed that a spillover event involving marmots (long-term hosts of plague in the Inner Asian Mountain Corridor) connected the disease in those wild rodents to commensal rodent-flea transmissions involved in shipping grain through Mongol military supply chains. This would have happened during the decades of active military campaigning, from the 1210s to the 1250s. About 90 years later, the process repeated in the region of the Black Sea and the Caucasus, where a new plague focus apparently had been seeded. Hannah Barker, in a brilliant deconstruction of sources from Venice, Genoa, and Mamluk Egypt, pinpointed grain supplies as being the most likely mechanism moving plague out of the territory of the Golden Horde and across the Mediterranean. In neither case, either in the 13th or the 14th century, so far as we know, was there any awareness of how or why the disease was spreading. The “bioterrorism” story that has been told repeatedly since Gabriele de’ Mussi’s chronicle was rediscovered in the 19th century is a fiction.

That story about plague-ridden bodies being catapulted over the walls of Caffa relates to the Mongols of the Golden Horde. But there is also a Black Death origin story that connects with the Mongols of Yuan China. This story has several layers of retelling, but its roots can be traced back to the 14th century, right when the disease newly presented itself in the Mediterranean. As Nahyan Fancy and I explain in a new paper, reactions to plague’s initial arrival in Persia, Syria, and Egypt in the late 1250s—if 13th-century writers delved into the “cause” at all—framed it in terms of a miasmatic atmosphere created by the Mongols’ destruction of Baghdad. The invading forces didn’t bring plague to the region; they caused plague to arise out of the killing fields left in their wake.

After 1258, plague seems to have gone underground, at least in the west, its own recent “origin story” slowly forgotten. In the 14th century, when plague reared its head again, even more ferociously, a handful of travelers returning from China, including Ibn Battuta, reported on a major plague outbreak in northeast China in the 1330s. Other outbreak news likewise seems to have quickly accumulated. This hearsay is why writers in the Middle East and al-Andalus spoke of a transcontinental Eurasian plague experience; one of them, Ibn al-Khatib, believing that miasmatic conditions could be spread long-distance by winds, actually understood the internecine wars in northern China as the origin of the pandemic in the Mediterranean. Importantly, there was no opprobrium in their accounts of these recent events; rather, it was more a sense of shared ill-fate.

The environmental explanation for plague that coalesced in the Arabic-speaking world was not universally shared within Europe, however. Rather, uniquely, many parts of Europe looked locally for a cause of the devastation. As Tzafrir Barzilay is now documenting, what had been fairly generalized accusations of well-poisoning early in 1348 turned decisively into accusations against Jewish communities in the late summer of that horrific first pandemic year. At least 300 communities were targeted across southern and central Europe in the following year and a half; some were completely exterminated.

Those were the events—coming out of early understandings of plague’s origins—of the 13th and 14th centuries. In the here-and-now, however, it is not enough for us to analyze and deconstruct how those medieval narratives came to be. We also need to assess their afterlives. Magda Teter, more than anyone, has put her finger on the urgency of looking at narrative afterlives, and of putting as much effort into deconstructing the process of selective remembrance and forgetting that allows some narratives to survive and others to be left on the wayside. For example, in an important analysis, she showed how slender a thread tied together accounts in 15th-century German chronicles that told repeated stories about the persecution of Jewish communities and the accusations against them. Once fixed in print, those stories persisted for hundreds of years, as did Hartmann Schedel’s iconographic depiction of a conflagration scene.

But even “persisting,” such stories may have been used differentially. And that is why it is crucial that we better understand the ways disease origin stories have changed, first in the era of growing international law tied to systems of quarantine in the early modern period, and then in the era of late 19th-century germ theory, when notions of atmospheric miasmas were replaced with far more specific narratives about hygiene and behavior generated in contexts of colonial control and global labor migrations. To imagine a direct, unbroken chain linking 13th– or 14th-century narratives about the late medieval plague pandemic to our current moment is as problematic for explaining current-day anti-Asian sentiment as it is for explaining present-day anti-Semitism.

III. The Art of Flower-Arranging

I am indeed “from” Japan. I was born there, at a United States military hospital, while my father served in the Air Force; my mother, of course, was there, too. The locus of my birth doesn’t have much to say about the child or adult I became. I have no conscious memories of Japan. I don’t speak Japanese and have never been back to visit. But my origin story is very important to me: in connecting me to the woman my mother was, it allows me to glimpse the delight she got from flower-arranging, a craft she studied during her sojourn in Japan. It allows me to understand the extraordinary conviction she had when, returning to the U.S., she and my father spent the better part of the next decade fighting against racism back home.

We need to look at both origins and processes of endurance. Plague has “plagued” human populations across the Eurasian steppe for at least 5000 years. And it is likely that humans were directly involved in much of that disease transmission—not, again, because humans carried the disease in their own bodies, but because, as humans doing what humans do, they caused environmental disruptions that created opportunities ripe for new interactions between microbial, animal, and human life. People in the lands we now call China have been, and still are, among plague’s victims. The same is true of all the other globalized infectious diseases, up to and including COVID-19.

As the histories of the world’s major infectious diseases continue to be revised and refined thanks to revolutionary new analyses in the sciences, different time periods, different continents, and different contextual circumstances will be implicated in disease origin stories. Those narratives must necessarily be geographically specific. But it is our job to make sure that those narratives are also humane. Never before have we had so much knowledge-generating capability. And not just in the sciences, but in humanistic fields as well. We need all-hands-on-deck against the challenge of infodemics: expertise not simply in genomics, but in rhetoric; not simply in isotope analysis, but in the ways religion and art and language shape the experience of disease.

Things can be true—they can be facts—but tell no meaningful story. Our skill, our craft as story-tellers, and our self-awareness of our role in wielding that craft, has never been more necessary.


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