The history of infectious disease has to be history on a global canvas. Pathogens don’t respect political borders, and health inequity is historically inextricable from patterns of wealth and power. Disease is integral to all the big questions of global history — questions about long-run economic development, connectivity and encounters, colonialism, and imperialism. The recent review essay by Dr. Monica Green in LARB in response to my history of infectious disease explores the question of how well the book achieves its global intentions. I am grateful for a lengthy review essay from a colleague who shares my enthusiasm for new kinds of genetic evidence, and I appreciate the valuable discussion of how historians can draw from this exciting and rapidly growing source of data. But given the focus of Pasts Imperfect, I would like to continue the discussion of how we might pursue a global history of disease. The review is mostly a missed opportunity in this regard, because it prefers to assert that the book is stilted toward a “Western and wealthy” perspective. Unfortunately, this criticism rests on a curious and complete refusal to engage the book’s extensive treatment of non-Western experiences.
To take a representative example, it is claimed that the book’s effort to periodize the deep history of globalization is Western-focused, because it does not register the dispersal of peoples throughout the Pacific and the Americas as a phase of globalization. The dictionary definition of globalization is the integration of distant societies across space, and historians will forever debate how to configure the processes driving connectivity in the past. But it is unusual to characterize dispersal as a form of integration (and thus as a process of globalization in the conventional meaning). It would be fair enough to argue that we need a different definition of globalization, but it is surprising that the reviewer neglects to mention that two chapters do treat the dispersal of humans over the globe, at great length. A reader of the review would take away the impression that a major theme of the book is simply missing, rather than classified differently than the reviewer would apparently wish.
Unfortunately this omission is not the exception, but rather the rule. To take another example, the review criticizes the book’s opening vignette, which asks readers to think about some of the daily routines and technologies that many people use to sanitize their bodies and domestic environments. Far from being tone-deaf, the passage begins by asking readers to think about the quotidian experiences familiar to those who “are privileged enough to live in a developed society.” Moreover, the accusation that such a generic routine is necessarily Western is surely tendentious. After all, in non-Western societies, many people (though of course not all) have access to improved drinking water, toilets, and electricity. To assume that turning on the light switch, using a flush toilet, and washing your hands is the exclusive privilege of Europeans is false (and perhaps a little parochial). But worst of all, it would have only been generous, not to mention responsible, to note that this vignette is followed, immediately, by a stark declaration that the extent of control over infectious disease remains unequal around the globe, as a way of setting up the problem of geographic health disparities as a central theme of the book.
In any case, those instances are reflective of a pattern, which means we have missed an opportunity to ask critical questions about what makes for a good global history of disease.  In my view, writing a global history of disease requires an earnest effort to capture as much of the varied human experience as the sources will allow, without naïvely assuming that any one society’s experience was normal. How can this be achieved in practice? In the history of disease, I suggest three strategies:
First, we should widen the infectious diseases that we write about beyond the usual suspects. Smallpox, plague, measles, typhus, tuberculosis, etc., are all canonical, and indeed must be central to the story. But we should recognize that this list leaves out important diseases, many of which are geographically constrained to the tropics and subtropics. In practice, for instance, I have tried to give ample coverage to schistosomiasis, lymphatic filariasis, falciparum malaria, yellow fever, yaws, and trypanosomiasis. All of these afflictions were absent or marginal in Europe, yet hugely important in human history. In general, any book that devotes as much space to these diseases as to the more cosmopolitan ones is probably not egregiously Europe-centered. Regrettably, this coverage is not even mentioned in the lengthy review, so a reader might come away with a mistaken expectation of what is in the book. It represents a missed chance for critical discussion about how expanding the range of diseases could more authentically represent the human experience from a global perspective. Moreover, we will need to take seriously these too-often-neglected tropical diseases to seek out the deep role of geography in human history.
Second, we can decenter narratives of the classic diseases like plague and smallpox, to avoid the misleading impression that somehow the Western experience was paradigmatic. In the case of plague, for instance, both the genetic evidence (as Dr. Green has shown elsewhere) and non-Western written evidence can be tools to revise the traditional narratives. In the case of the Black Death, for instance, we can (and I try to) let the rich Arabic sources have as much space as the European sources. We must also ask hard questions about the impact and timing of plague in China, South Asia, and Africa, too. The history of smallpox is probably more challenging, for now at least, but I have tried to reframe the conventional story of the “Columbian Exchange,” in which Europeans brought smallpox to the New World with deadly effect in the 16th century, by putting it in a wider, planetary perspective. Smallpox was a bigger problem, everywhere, starting in the 16th century, from Mexico City to Ming China. Sometimes with striking synchronicities, it raged across the planet, from the American Southeast to late Stuart England to early Qing China. In my view, we don’t fully understand why this was so, but a global perspective prompts us to question the blinkered model of the “virgin-soil” epidemics in the New World.
Third, we should try to understand the progress of the last two centuries from a global perspective and not simply a Western triumphalist one, such as is sometimes dominant in the economics literature. Even a global perspective will still need to devote due attention to Europe’s pioneering role in many facets of public health and biomedicine. But, critically, we should recognize that as modern growth and globalization fueled great health crises (like cholera, the Third Plague Pandemic, and the 1918 influenza), the power dynamics of European imperialism and incipient capitalism meant that health and processes of modernization were deeply entangled, to the disadvantage of many non-Western societies. Rather than seeing modernity as a period of unbroken and continuous triumph, we should try to recognize the complex and sometimes causal relationships between progress and inequity. At the same time, we should also try to offer an honest assessment of the globalization of good health — the upward convergence of health outcomes in the 20th century, as developing societies in the age of decolonization rapidly embraced the opportunities to bring infectious diseases under control. One would never guess it from the review, but non-Western experiences of modern development get the majority of the space in the last two chapters of the book.
When you deliberately excise all of the non-Western material, what is left unsurprisingly looks like “Western civ.” But such selective reading doesn’t really advance the cause of global history. Meanwhile, there are genuinely severe challenges in trying to tell the story of infectious disease on a global canvas. Our energy would be better focused on a good-faith discussion of the big methodological and substantive challenges we all face. For instance, the historical demography literature — so valuable in trying to understand how people died in the past — is wildly skewed toward Europe. So is the paleogenomic evidence, at present. How do we get around these biases in the source material, using what we know from this evidence to make inferences about pre-modern societies, without naïvely assuming that what we have is actually universally representative? More conceptually, the entanglements of geography, power, and disease are probably among the most complicated questions we can ask about the history of economic development. Economists have been (much) better at helping us understand the causal factors behind improvements in health, but historians have done a better job at treating non-Western experiences and the problem of imperialism. How can we achieve a disciplinary rapprochement? I do not claim to have overcome these problems, only to have confronted them earnestly from a global perspective.
Monica Green Responds to Kyle Harper:
I thank Professor Harper for his detailed reading of my review and his recognition of its call for dialogue on the pressing question of how “global health” is to be defined and its history pursued in a way that is meaningful for all humanity.
Kyle Harper is professor of classics and letters at the University of Oklahoma.
Monica H. Green is an expert in the history of medicine in premodern Europe and global infectious diseases.
 Also notably unhelpful is the insinuation that the simpler terms “time travel” and “tree thinking,” used as shorthand for the unwieldly technical terms “paleogenomics” and “phylogenetics,” are my “cute” “nicknames.” Time travel comes from Svante Pääbo and Johannes Krause, two founders of the field, and tree thinking is commonly used as well as the name of one of the standard monographs on how to employ phylogenetic reasoning. In my view, pedantry will not help us as we all work hard to bridge numerous disciplines with their sometimes demanding technical language. Furthermore, I am at a loss to understand how “tracking” is a third distinct method of using genetics. What is described as “tracking” in the review is simply phylogenetics (tree thinking) or perhaps its spatial application, phylogeography. I am unfamiliar with specialists in the field who have previously considered this a way of using genetic data entirely apart from phylogenetics.