Plagues in World History (3 page)

lines of his thought. In the first place, whole books have now been devoted to the role that disease played in history, instead of the subject occupying but a minor part in the broader historical narrative. The traditional approach (sometimes also called the “positivist” or “biological” school) of modern historical writing is to follow most ancient authors in treating disease as a discretely defined, exogenous, or foreign variable (now a microorganism rather than an arrow from on high) that suddenly invades a population and wreaks havoc upon it. Taking their cue from Thucydides, who emphasizes how the death from plague of one man, Pericles, altered Athens’ subsequent fortunes in the Peloponnesian War, these writers stress the almost whimsical role that disease has played in dramatically changing the lives and course of historical personalities and events.25 Aligned with this approach are those historians who chronicle humans’ heroic struggle to medically “conquer” the biological enemy represented by disease, a war that mankind, until recently, seemed to be winning as history progressed.26

Then along came William McNeill’s
Plagues and Peoples
in 1976, which some would consider as bringing about a seismic shift in historical studies of disease.

McNeill himself claimed to be writing a new chapter in disease history, ascribing to epidemics an importance not previously found in historical surveys. Even though McNeill did pay homage to “antiquarians,” such as Hans Zinsser, for pointing out isolated disease incidents such as the Black Death that briefly commanded the historical stage, such acknowledgments, he claimed, were rare and made historians uncomfortable because they did not fit in with their orderly views of the past.27

By contrast, McNeill, a world historian who emphasizes cultural fusions among different civilizations that eventually led to Western dominance of the globe,28 adapts this approach to disease in order to accord it a central place in world events. This is especially the case when new technologies or cultural developments enable a disease to become “pandemic,” that is, to be communicated to distant lands far from its epicenter and thus have a dramatic impact on “virgin soil” populations with no prior exposure or immunity to it. McNeill’s classic example of this, and the one that actually inspired his book, is the introduction of smallpox to the Americas in the early sixteenth century and the resulting horrific mortalities among Native American populations there; according to McNeill, smallpox by itself is sufficient to explain how conquistadors such as Hernán Cortés and Francisco Pizarro overcame overwhelming odds to swiftly conquer the once-mighty Aztec and Inca empires in Mexico and Peru.29 In addition to such “transoceanic exchanges,” McNeil devotes another chapter to the role played by the Mongol Empire during the late Middle Ages in the dissemination of the Black Death, both east and west. His concluding chapter is perhaps his most conven-10 y Introduction tional, tracing the now familiar success stories of modern medical science in conquering disease from the eighteenth to the twentieth centuries.

So far, nothing that McNeill has to say is exactly new; as a matter of fact, most of what is mentioned above could be fairly said to have been anticipated by the ancient historian Thucydides. For it was Thucydides who first pointed to the world scope of disease, to its devastating impact upon a population unprepared for it, and even to the central role disease could play in history. But I believe that McNeill has made two contributions to the history of disease that are important and unique.

In the first place, McNeill introduces the idea that disease can be a relative construct, not just a discrete biological entity. Although McNeill uses “macroparasitism” to refer to one class of human beings living off the productive capacity of another class, one can also conceive of it in environmental terms, in which humans through their variegated behaviors alter their disease environment, which in turn adapts to their modifications, and so on in an unending war of mutual attrition; in many respects, this is comparable to how microparasites have adapted to their human and animal hosts, selectively evolving to neither kill them outright nor in turn be eliminated completely. In this way then, human beings can, in effect, create their own sense of just what is a disease. McNeill fully realizes that this can change “the very concept of disease,” making it entirely dependent on social and historical circumstances. As an example, nearsighted-ness and a “dull sense of smell” may be considered perfectly normal in today’s society, but they would have been crippling debilities—indeed a disease—among Paleolithic hunters struggling to survive. However, McNeill rejects a completely relativist approach to disease, preferring to hold onto “a firm and universal nu-cleus to the concept of disease,” one in which “bodily disorder” mainly arises from “parasitic organisms.”30

Despite McNeill’s reservations, the relativist, or “social constructionist,” approach, which increasingly viewed disease as an endogenous phenomenon arising solely out of factors intrinsic to the society or culture in which it occurs, became more popular among historians, particularly during the 1980s; for it was at that time that the emerging AIDS pandemic seemed to be a perfect illustration of how a disease can be a function of socially risky behaviors.31 Indeed, one historian in this school goes so far as to suggest, perhaps facetiously, that one day harmless skin freckles may be deemed unsightly enough to be classified as a disease, complete with a “National Institute of Freckle Research” devoted to eradicating them.32

However, if one goes to extremes with such an argument, one wonders what historical statements, if any, can be made about disease, if the very definition of the term is subject to such speculation. It seems that McNeill was right to insist upon a commonsense foundation from which to start a discussion.

McNeill’s other contribution comes at the end of his book, where he speculates about the future of disease history. Despite the fact that
Plagues and Peoples came out at the very same time that the World Health Organization was successfully eradicating smallpox, and in stark contrast to traditional views of medical historians that foresaw an “end to epidemics,” McNeill concludes that infectious disease will remain an inseparable part of the history of humanity, indeed, for as long as humanity itself continues to exist. Ironically, he sees the very success of medical treatments of disease as only contributing to its perpetuation. A good example is the rash of polio infections that broke out among even the higher classes of American society in the mid-twentieth century, a circumstance attrib-utable, McNeill insists, to the higher standards of hygiene that wiped out minor infections among children, which earlier had conferred some immunity to more serious, full-blown infections.33 In a new preface written in 1997 to take account of the current AIDS pandemic, McNeill maintained his pessimistic view of humankind’s ability to “conquer” disease, citing the worldwide AIDS crisis as just one more example of how the global transmission of disease was only accelerat-ing the biological evolution and adaptation of microorganisms to their hosts.34

The efforts of humanity—the “macroparasite”—to wipe out disease were upset-ting the natural balance and, as recent disease history made clear, was only making things worse, not better. This gloomy perspective has been taken up by a host of far less restrained authors who peddle an alarmist, even apocalyptic, scenario where disease in the end conquers humankind, not the other way around.35

On a very basic level, one can both agree and disagree with McNeill’s thesis that disease has played a central role in human history. It seems an intuitive fact that most people who die a “natural death” do so as the result of some disease or other, rather than being blessed with the good fortune of dying of extreme old age, when the cells of the body simply cease to divide and function. In this regard, disease is almost as ubiquitous as death in terms of its presence and importance in our everyday lives. Yet, one could also argue that the very fact that populations around the globe are increasing in number, and have done so at varying rates of propagation throughout history, prove that human fortunes are rarely dictated or limited by disease and its consequent mortality. Instead, one might counter that it is restrictions on reproductive capacity (aside from disease) that have played the greater role in the course of human development, such as the availability of food and other material resources that, from a Malthusian point of view, are forever locked with population in a struggle to achieve equi-librium or balance.36 In a way, McNeill has sidestepped this whole conundrum by only focusing on large-scale, global pandemics of disease, whose mortalities posed extraordinary challenges to civilizations. His example, by necessity, will be followed in this book.

12 y Introduction

Nonetheless, even within McNeill’s more specialized construct, his thesis has been attacked on two other fronts by revisionist scholars of disease. One group has made the case that disease does not act on its own when impacting human history; rather, it wreaks its devastation only in conjunction with other historical forces, such as the oppressive policies of colonialist/imperialist powers that inten-sify disease’s morbidity and mortality.37 This is true despite the fact that in some cases colonial powers believed they were acting in the best interests of their native subjects, such as by imposing Western standards of hygiene and medicine upon longstanding traditions of healing and customary responses to disease. Native resistance to high-handed health measures—such as hospitalization, isolation of contacts, disinfection, and quarantine—could effectively blunt their intended benefits. Given that, in some places, such as the Americas or the Pacific Islands, the sheer mortalities of imported diseases assuredly outweighed any medical blessings imperialism supposedly bestowed upon a conquered people, even when the benefits of modern medicine had material effect, imperialism could still amplify disease’s impact since these same benefits also allowed Western soldiers and colonists to intrude longer and more deeply into previously inhospitable areas.38 All this implies that McNeill had accorded an overmighty role to disease on the stage of history, which now should give way to a more nuanced, complex interplay with other factors.

Yet another contingent of historians besieged McNeill’s edifice on the grounds that he was too consistently negative about the impacts of disease upon its victims.

Instead, it could be argued that disease brought some benefits for certain elements of society, who might even welcome its arrival among them. This debate has been played out especial y with respect to the Black Death in Europe during the late Middle Ages. McNeill claimed that the ravages of the Black Death, whose mortality in Europe during its first outbreak in the mid-fourteenth century was as high as 50 percent on average, instilled a “fatalistic” or even “suicidal” mentality upon the collective consciousness of Europeans.39 But more recent scholars of the Black Death have argued that it set in train necessary “transformations” in many areas of medieval society, including ushering in a more capitalistic-based economic system, new technologies such as the caravel and the printing press, a more empirical approach to science and medicine, and even the Renaissance and Reformation with their greater emphasis on individual portraiture and piety.40 Not even McNeill’s classic case study of “virgin soil” American populations wiped out during the colonial period was immune from this argument, for some native groups, such as the Tlaxcala people of Mexico, actually benefited from the decimation of their rivals and overlords, chiefly the Mexica, on Lake Texcoco.

To take a more modern example of “always looking on the bright side” of disease, at least from a certain perspective, the ongoing AIDS pandemic is seen

to have brought about a decline in risky social behaviors, such as sexual promiscuity, that are believed to be major contributing factors to propagation and incidence of the disease. But inducing greater morality in human society is traditionally seen to be the exact opposite of disease’s usual impact, going back to Thucydides.41 On a more prosaic level, AIDS has been a boon to Western pharmaceutical companies, which have been able to profit from antiretroviral drugs and “protease inhibitors” that inhibit full-blown symptoms of the disease almost indefinitely. AIDS has thus created a stable pool of captive customers for “Big Pharma’s” products, which will remain the case for as long as a vaccine or cure for the disease remains elusive. Meanwhile, the disease has also created a very large and cheap pool of human “guinea pigs” for trial treatments for AIDS, since the expense of such treatments would otherwise be prohibitive to the vast majority of victims throughout the third world, which is now bearing the brunt of the global AIDS pandemic.

This brings us back to the question with which we opened this chapter: why study disease? Nearly every writer on the topic since Thucydides has clearly demonstrated that disease has had a big impact on human history, and—McNeil is surely right here—it will continue to do so for the foreseeable future. But what about the reverse—the impact that humans can have on disease? For I would argue not only that disease has shaped the history of our predecessors but also that humans have been able to redirect its course and meaning in history. I am particularly fascinated by those moments when civilizations around the world were severely impacted by a disease’s mortality and morbidity, such that their very continued existence was in the balance. For it is at times such as these that human responses to disease assume their greatest importance. Yet, neither can such trials that test or temper a society occur without a very real biological disaster occurring among human populations and very often among the animals that live with them as well. While tribulations of the requisite magnitude or global scale may be relatively rare, they nonetheless will form the focus of this book. I hope to demonstrate from al this that humans can alter the extent to which they suffer from disease, even when this calamity seems to come, as the ancients truly believed, like a bolt from the blue. While some historians may not like studying disease for this very reason, in actual fact its course throughout human history has been far from arbitrary. Indeed, this is what makes disease such a fascinating topic of study. Unlike some other themes in history that have become trendy these days, such as the effects of climate change,42 disease has allowed humans to change their fate at its hands, instead of simply being subject to it. Even without the awesome power of modern technologies, men and women could have a relationship with disease that was not all one way. Humans have thus made their own history of disease even while it was also happening
to
them.