Our contribution here seeks to demonstrate how African history can draw from, contribute to, and perhaps reorient biomedical debates. It suggests, too, a very different model for pursuing historical research: our expanding collaborative research not only brings together historians with diverse fields of expertise, but it also puts us in dialogue with virologists, epidemiologists, primate scientists, and evolutionary biologists. Our goal in describing this work is to stimulate historians of Africa to consider how their research on social and cultural histories of environmental change, resource exploitation, urbanization, and medicine might concretely contribute to pressing global health questions about disease emergence.Footnote 1
Our specific collaboration addresses the historical emergence of HIV, a topic that has received considerable attention from biomedical researchers, but far less from historians of Africa. Indeed, although the emergence of this pandemic disease has preoccupied researchers for more than three decades, our own collaboration has developed only in the last few years.Footnote 2 Publications concerning HIV ‘origins’ in Africa over the past decade have burgeoned; in 2011–2 alone, two major books and four articles in prominent biomedical journals appeared in print.Footnote 3 Not a single historian of Africa authored or coauthored these publications. Biomedical researchers and journalists have, of course, consulted historians to gain their perspectives on the history of HIV in Africa, but relatively few historians have themselves published on the question of HIV's beginnings and expansion.Footnote 4 Interestingly, biomedical publications most frequently cite one historical analysis conducted by anthropologists, none of whom is a specialist of equatorial African history – a regional expertise that would appear to be crucial for understanding the processes of HIV emergence during the first several decades of the twentieth century.Footnote 5
Are we merely patrolling disciplinary boundaries, fearful that non-historians are usurping our authority, or do historians really have something crucial to offer in debates about HIV emergence? Our contention here is twofold. First, virologists, evolutionary biologists, and other biomedical researchers have conducted important historical research about which historians of equatorial Africa should be aware. Recent advances in virology, phylogeny (the study of evolutionary relations between living beings), and population genetics have facilitated the development of powerful tools to analyse the DNA sequences of pathogens, and thus to study the history of epidemics. These new tools of genetic analysis offer an unprecedented opportunity for historians to revisit the environmental, medical, and social histories of Africa and the Atlantic world. And second, we argue that while biomedical researchers agree on the contributions of broad historical changes to HIV emergence that occurred in the first half of the twentieth century, historians of Africa have much to offer: we can mobilize historical methodologies to shed light on the contexts and specific dynamics that on several occasions transformed simian viruses into human ones, including the pandemic HIV/AIDS.
WHAT WE KNOW AND DON'T KNOW ABOUT HIV EMERGENCE
We use the term ‘emergence’ to refer not only to a pathogen's adaptation from one species to another, but also to the historical context that permitted its transformation from localized infection into a global pandemic.Footnote 6 Readers may already know that there is more than one Human Immunodeficiency Virus (HIV). The pandemic virus afflicting much of the world, including large parts of Central, East, and southern Africa, is HIV type 1 group M (HIV-1M); virologists have identified its beginnings in a Simian Immunodeficiency Virus (SIV) that has affected a subspecies of common chimpanzees (Pan troglodytes troglodytes) living in the rain forests of south-eastern Cameroon, perhaps for millennia.Footnote 7 There are three other HIV-1 viruses (groups N, O, P) that emerged from other non-human primates, including western lowland gorillas, but these viruses account for a miniscule proportion of all HIV infections. A second large group of HIVs is HIV-2, which emerged in human populations from sooty mangabeys (Cercocebus atys atys) in the forests of Guinea Bissau and Côte d'Ivoire, and now account for about 5 per cent of all HIV infections.
Because HIVs evolve as they are transmitted, virologists can identify differences in DNA sequences of multiple virus samples from different times. This analysis permits them to project back in time the date of the common source (referred to as the Most Recent Common Ancestor, or MRCA), presumed to be the date of the earliest adapted human virus. Generally, these studies demonstrate that the HIVs crossed over to human populations on several independent occasions during the first part of the twentieth century in West and Central Africa. For the pandemic HIV-1M, discovered in the early 1980s, the estimated dates of this host shift ranged between 1919 and 1945 (median 1933); subsequent analysis moved the dates back to 1908 to 1933 (median 1921).Footnote 8 The less widespread, less aggressive HIV-2 virus has been studied less, but researchers have suggested that its groups A and B emerged in human beings in Guinea-Bissau between 1940 and 1945 and became epidemic during the country's independence war (1963–74).Footnote 9 Why and how these crossovers took place has constituted the focus of much biomedical debate, and as readers will readily notice, such questions are fundamentally historical ones.
Over the past two decades, researchers have offered a multitude of explanations for the mechanisms of the simian virus's adaptation to human beings, and for the broad contextual factors that facilitated human exposure to and transmission of the virus. In the late 1990s, journalist Edward Hooper argued that a contaminated polio vaccine was to blame for the virus's crossover to human beings, although subsequent studies categorically disproved the claim. Since then, biomedical researchers have generally accepted that exposure to chimpanzee meat was a more plausible source of zoonotic infection.Footnote 10 They have focused on the broader historical circumstances facilitating human-to-human transmission of the virus, considered the limiting factor in the emergence of pandemic HIV. Preston Marx and Ernest Drucker proposed a ‘serial passage theory’, in which the virus passed ‘serially’ between patients, possibly through contaminated syringes used on several patients, thus increasing the virus's virulence and capacity to adapt to its human host.Footnote 11
More broadly, many biomedical researchers have focused on the imposition of colonial rule and, at times, particular processes that it unleashed. In a frequently cited piece on the MRCA of HIV/AIDS, evolutionary biologist Michael Worobey and colleagues first suggested that the establishment of Leopoldville (now Kinshasa) as Belgian Congo's capital, and more generally ‘[t]he rise of cities’ and ‘the founding and growth of colonial administrative and trading centres such as Kinshasa’ caused Central Africa ‘to become the epicentre of the HIV/AIDS pandemic’.Footnote 12 Anthropologists Amit Chitnis, Diana Rawls, and Jim Moore also focused on changes effected by colonial rule in Belgian Congo, including conscription and forced labor, social turmoil, the disruption of ‘traditional’ sexual practices, and massive vaccination campaigns.Footnote 13 Recent interventions on the ‘origins’ of pandemic HIV have ranged from highly specific (genital ulcer diseases in ‘promiscuous urban communities’) to broad, multi-causal factors (prostitution, human mobility, and mass medical campaigns within the changing sociopolitical context of colonial rule).Footnote 14
The best known analysis actually written by a historian is John Iliffe's The African AIDS Epidemic, which offers a historical synthesis of Africa's AIDS epidemic up to 2006.Footnote 15 The first two chapters provide an admirable overview of the first host shift through the epidemic's expansion in Central African urban centers. In keeping with the aims of this historical synthesis, Iliffe reports – but does not critique – the broad explanations cited above for HIV's beginnings:
colonial innovations … [such as the] penetration of the forest for hunting, rubber collection and logging; increased viral transmission through labor concentrations and vaccine campaigns against sleeping sickness and smallpox; and the adaptation of the virus to humans through rapid passaging by arm-to-arm inoculation that would have the effect of accelerating evolution.Footnote 16
Of HIV-1M's expansion within western equatorial Africa, Iliffe summarizes a rich epidemiological literature from the 1980s to document how, from the 1970s, HIV expanded among ‘a minority of vulnerable individuals in wide networks of ephemeral sexual relationships in which the men were significantly older and wealthier than the women’ in Kinshasa.Footnote 17 He also explains how the epidemic's spread varied considerably in other equatorial African cities and countries – the consequence of different virus strains, transportation networks, gender relations, and sexual practices.
Iliffe's masterful synthesis was not, however, the last historical word on HIV's beginnings. Tinderbox, recently published by Washington Post journalist Craig Timberg and epidemiologist-anthropologist Daniel Halperin, is an indictment of colonial rule for triggering the AIDS pandemic and of contemporary global health actors for its intensification in Africa.Footnote 18 Drawing from secondary historical sources, the authors argue that colonial rule transformed HIV from what might have been a ‘dead end’ into a global pandemic: German colonial rule in south-eastern Cameroon triggered new human mobility, propelling an HIV-infected person (hunter, porter, or trader) to colonial Kinshasa, where ‘sexual license’ increased viral transmission; expanding transportation networks then catalyzed HIV's explosion elsewhere in equatorial Africa and, ultimately, the world.Footnote 19 Timberg and Halperin's account is highly selective and relies on stereotypes of Central Africa's past, caricatures African ‘sexual behavior’, neglects a serious analysis of medical practice, and provides only snapshots of historical moments rather than accounts of fully developed historical processes that might have facilitated HIV emergence.
Some biomedical researchers digging away at HIV ‘origins’ have worked in historians’ hallowed grounds – the archives. Joao de Sousa and colleagues plumbed secondary literature and archival holdings in France and Belgium to argue that an ‘unprecedented’ epidemic of genital ulcer disease (GUD) among prostitutes and their African clientele in 1920s Leopoldville effectively facilitated HIV transmission.Footnote 20 Epidemiologist-physician Jacques Pépin in 2011 published The Origins of AIDS, drawing from colonial archival sources in Belgium, France, Canada, the United States, Switzerland, and the Netherlands. The resulting work is an impressive effort to trace HIV-1M's ‘origins’, from the Cameroonian ‘cut hunter’ (the almost mythical progenitor of the HIV pandemic), to the cataclysmic changes unleashed by colonial rule in the cities of Brazzaville and Kinshasa and forced labor projects such as the Congo-Océan Railway, population expansion, human mobility, urban gender imbalances, sexual and domestic activities of femmes libres, and sexually transmitted diseases.Footnote 21 Echoing claims of researchers Marx, Drucker, and Alcabes, and Gisselquist, he highlights the contributions to HIV emergence of mass injection campaigns and unsterile injection practices against sleeping sickness, yaws, syphilis, tuberculosis, and malaria.Footnote 22 For Pépin, contaminated needles were not the mechanism that adapted the simian virus to human beings, but rather a key mode of transmission that magnified HIV's initial spread. While not always in a form that historians would easily recognize, these writings on the ‘origins’ of HIVs constitute histories that contribute importantly to our understandings of when and why HIV-1M and HIV-2 became epidemic.
Yet these explanations fall short in ways that historians of Africa could actively remedy. First, these writers do not always evaluate critically colonial sources and interrogate the political and professional interests that shaped colonial claims.Footnote 23 Thus, while these researchers use written evidence as if it offers undisputable proof of past reality, historians of Africa recognize well the blind spots, biases, predilections, and broader contexts of such primary sources that shape their interpretation, and that these sources and the archives that house them, are not simply, as Ann Laura Stoler puts it, ‘sites of knowledge retrieval but of knowledge production’.Footnote 24
A related methodological shortcoming involves the sources that have gone entirely unexplored in debates about HIV beginnings. While biomedical researchers have largely confined their analyses to secondary literature and colonial medical and other documents, historians of Africa have a rich tradition of investigating a much wider array of sources – oral historical testimonies, material culture, the popular press, photography, particular technologies – that could offer insight into changing relations and practices that facilitated HIV emergence. Histories of HIV emergence would benefit from close analyses of how African social and professional groups depict changing hunting and butchering technologies and practices; mobility; gender relations and domestic, sexual, and livelihood practices in urban centers; and medical practices in hospitals and clinics. Such histories would be further enriched by attention to social, political, economic, and cultural conditions that produced varied sources.Footnote 25 This kind of historical work could move HIV emergence histories beyond single factors, ‘smoking guns’, and caricatured colonial histories of Africa. Instead, it would locate such ‘factors’ within ongoing processes of political economic, social, and ecological change and longer-term continuities.
Second, almost all biomedical and other works cited above focus exclusively on change, not on historical continuities: with dates of HIV emergence in hand, they seek out what they presume to be new developments, but they fail to contextualize such changes in a longer historical framework. To be sure, German, French, and Belgian colonial rule imposed important new political and economic relations on equatorial African societies, but certain practices and processes were well under way in the eighteenth, nineteenth, and twentieth centuries, including human mobility, long- and short-distance trade, markets, and hunting.
Third, biomedical writings have tended to focus on large-scale, traumatic transformations and events that may have contributed to HIV emergence, but have overlooked everyday practices. Urbanization, prostitution, sexually transmitted diseases, and disease control campaigns have all been mobilized to explain HIV emergence.Footnote 26 This is quite right, but we would argue, too, that historians' attention to more mundane, daily practice can potentially illuminate much about HIV emergence: the use of blood transfusions as therapy, the conduct of daily medical care, making a living in urban centers, and the historical participants in and practices of hunting and butchering of game. In the following section, we assess the historical literature and raise additional historical questions that can be posed about the daily practices surrounding each of these topics (medical care, hunting, and urbanization and migration) that can shed alternative light on HIV emergence.
Finally, biomedical researchers’ relentless search for the ‘smoking gun’ of HIV ‘origins’ should itself raise questions.Footnote 27 That biomedical sciences persistently seek such ‘origins’ should come as no surprise to us, for this quest is a hallmark of biomedical sciences’ ways of knowing, and particularly of epidemiology. But the pursuit of an ‘origin’ should make historians ill at ease. In the early 1970s, Michel Foucault characterized the search for ‘origins’ as a futile ‘attempt to capture the exact essence of things’ and to recover a pure ‘truth’. He proposed instead ‘historical beginnings’ to capture ‘the accidents, the minute deviations – or conversely, the complete reversals – the errors, the false appraisals, and the faulty calculations that gave birth to those things which continue to exist’.Footnote 28 HIV emergence is so profoundly entangled in ongoing human social, political, and ecological processes and moments of historical rupture in equatorial Africa that for historians, any effort to delineate a moment of ‘origin’ might be considered a fool's errand.
HISTORIANS' CONTRIBUTIONS TO THE DEBATES
Historians, then, can mobilize our methodologies to reconfigure the questions that biomedical researchers pose about HIVs' ‘origins’. We can offer a more critical approach to a broader array of sources, an attention to continuity and change, as well as to the everyday and the cataclysmic. We know that the ‘historical beginnings’ of HIV emergence are messy, indeterminate, and contingent. Although there are other stories to tell about HIV-2 emergence in West Africa,Footnote 29 we focus below on developments in Central Africa, discussing how our methods and other sources can raise new questions that flesh out and complicate narratives of HIV-1M ‘origins’.
‘Cut hunters’ and historical continuities
That the pandemic HIV-1M came from a chimpanzee SIV localized in south-eastern Cameroon is widely accepted, but biomedical researchers have generated a mythical progenitor (the ‘cut hunter’) and narrative to explain the viral host shift from chimps to people.Footnote 30 Typically, analysts have signaled that the voracious demands of new colonial regimes intensified human activities in the forest, increasing the frequency of hunting, trapping, and butchering of great apes, and thus amplifying human exposure to the simian virus.Footnote 31 The infected person (hunter or trader) would then have traveled by steamer from an inland port (Moloundou or Ouesso) to Kinshasa.
But does this story make sense in terms of equatorial African history? Several fallacious presumptions undercut the notion that colonial rule intensified human contact with great apes: precolonial societies in equatorial Africa lived in peaceful isolation; they did not trade or have markets; they possessed no firearms and thus rarely hunted chimpanzees; and, based on contemporary observations of intensive game hunting, hunting expanded in linear fashion from the imposition of colonial rule.
Existing historical analyses not only challenge such assumptions, they can also raise new questions about HIV emergence. Historians of Africa have used an array of methods to demonstrate that Central Africans have long been in contact with great apes, and that the eighteenth and nineteenth centuries catalyzed significant human mobility through the forest, trade, hunting, and violence.Footnote 32 Relying on historical linguistics and oral histories, Kairn Klieman has shown that from the 1840s, northern equatorial forest societies were caught between intensive trading and slave raiding pressures from the north, east, and south; and they were highly geographically mobile and engaged in a dynamic long- and short-distance trade in guns, slaves, ivory, foods including meat, and other commodities.Footnote 33 In the Lobéké forests where the SIV ancestor of HIV-1M was identified, anthropologist Stephanie Rupp has collected oral histories detailing warfare and slave raiding, but also ‘intermarriage and mutual cooperation’ among Bakwele, Bangando, Baka, and Mbomam peoples.Footnote 34 Other studies have drawn from oral histories and early explorers’ accounts to demonstrate that many societies possessed firearms but also other technologies to kill chimpanzees or gorillas.Footnote 35 Thus, German, Belgian, and French colonization in the early twentieth century likely continued earlier processes and practices that exposed human beings to great apes.
Second, historical methods could flesh out or perhaps reorient the ‘cut hunter’ scenario. Biomedical researchers presume that the person was African and male, and that he likely took a steamer from the Sangha basin to Kinshasa. But was the hunter African? Europeans were heavily armed, and they hunted intensively for food and sport. Was the hunter male? Stephanie Rupp has demonstrated in the Lobéké that hunting and trapping have not been exclusively male practices. In the context of company and administration complaints about a grievous dearth of available African labor, would an African colonial subject even be permitted on a steamer to Kinshasa?Footnote 36 Such questions have thus far gone unexplored.
Further, oral histories suggest that hunting, trapping, and butchering practices in the northern forest changed over the twentieth century, as have local and colonial restrictions on who could kill or consume chimpanzees and gorillas.Footnote 37 Oral historical investigations might yield greater detail about these changing practices, proscriptions, and contexts of ape hunting or consumption. Colonial documentation suggests that the range of game hunters and the number of firearms expanded in the early twentieth century, and that demand for ivory and animal skins came from new colonial sources. But colonial control over this region was only slowly implemented, and colonial concessionary company demands for animal products may have redirected, rather than increased, game hunting.Footnote 38 Forest hunting most likely intensified in the mid-twentieth century, when commercial coffee, cocoa, and timber production expanded, concentrating workers in sites of exploitation and focusing hunting pressures in these areas. The effects of colonial game laws remain difficult to evaluate, but additional oral historical research might illuminate how consistently authorities applied them and how easily hunters circumvented them.Footnote 39 Our historical research would not question, of course, the host shift from chimp to human being. But it could derail a three-decade old biomedical discourse of an imagined history, and in its stead, draw from an existing literature, linguistic and oral historical sources to offer more robust historical contexts for HIV-1M emergence that can more usefully inform general understandings of interspecies transmission.
Urbanization, migration, and prostitution
The timing (1921–33) and location of pandemic HIV emergence necessitates a closer investigation of European colonial rule and its role in promoting urbanization, reorienting mobility patterns, developing transportation networks, and precipitating labor and military movement, all of which facilitated infectious disease transmission.Footnote 40 New urban centers and colonial construction projects expanded previously limited or non-existent practices and conditions, including denser settlement patterns, forced labor, and urban prostitution, particularly in Kinshasa and Brazzaville. Several developments may explain these cities’ prominence in HIV beginnings, but they require broader contextualization, attention to different sources, and closer analysis of colonial policies, interventions, and their wide-ranging consequences.
In contrast to biomedical researchers’ claims, Central African urbanization and demographic change began well before colonization: dense riverine networks had long facilitated the exchange of goods, ideas, and people through matrimonial alliances and slave trade.Footnote 41 The place that became Kinshasa lay on Malebo Pool, the last navigable expanse of Congo River linking the forest and the coast. Merchants stopped at Malebo Pool to trade, contributing to the expansion of this demographic hub. Its population reached at least 50,000 by the late nineteenth century.Footnote 42 Malebo Pool's urbanization and demographic growth continued with the imposition of Belgian and French colonial rule; Brazzaville served as the capital of French Equatorial Africa from 1910, and Leopoldville (future Kinshasa) became the capital of Belgian Congo in 1923. New administrative functions brought an unprecedented urban boom in both capitals.
Over the centuries, Congo populations had suffered several upheavals that facilitated disease transmission and stymied demographic growth, and colonial rule continued these long-term trends.Footnote 43 The transatlantic slave trade and, later, forced labor and concessionary company regimes all exposed populations to recurrent famine and epidemics.Footnote 44 Venereal diseases, sleeping sickness, and dysentery, afflicting Europeans and Africans alike, spread following colonial expansion.Footnote 45
Understanding why HIV-1M emerged in a narrow time window requires an analysis illuminating the dramatic social, cultural, and environmental change facilitating viral transmission. Shifting from conquest and rapacious resource extraction to a system that premised economic growth based on African labor, migration, and taxation, French and Belgian colonial powers exacerbated the conditions for disease transmission. Employment opportunities and the development of schools, hospitals, and churches brought rural migrants to cities and facilitated urban growth. Leopoldville's European population more than doubled between 1924 (1,224) and 1929 (2,766), and its African population grew even more, although many African residents lived under more constrained conditions: male workers found themselves confined to ‘urban’ temporary settlements lacking basic amenities; single women could not legally live there until the mid-1930s. In 1928, some 21,500 African men, but only 358 legally married African women, lived in Leopoldville. Still, by then, nearly 5,000 single women had been smuggled into the city.Footnote 46
This sex-ratio imbalance has prompted several biomedical studies to link urban prostitution to HIV emergence.Footnote 47 De Sousa and colleagues attribute an early twentieth-century syphilitic genital ulcer outbreak to the ‘origin, initial spread and adaptation of HIV’.Footnote 48 But in order to link HIV emergence to expanding sex work between 1890 and 1920, these authors project backwards by several decades a development that only began in the late 1920s and intensified after the Second World War.Footnote 49 Here, ‘sex work’ refers to occasional or regular transactional sexual services that individuals provide in exchange for money and/or goods. These activities, when they involve many sex workers who derive their income from them, tend to create a market and are usually defined by the term ‘sex industry’. As such, sex work did not exist in Central Africa before colonization, as several sources have attested, and, until World War II, the prohibition against single women legally residing in the city meant that ‘prostitution’ offered the sole possibility for their survival.Footnote 50
Yet the nature of this ‘commercial’ sex work demands closer attention than biomedical researchers have given it. Unlike prostitution in European cities, characterized by procurers, sex houses, and high turnovers, Kinshasa's pre-Second World War ‘prostitution’ entailed an array of sexual, affective, and domestic services that were offered to a few regular African and European customers in exchange for money, shelter, and food. As Amandine Lauro points out, the tendency to refer to such practices as ‘prostitution’, a misnomer in this case, reflected the colonial authorities’ ignorance of African urban life as well as their metropolitan obsession with the ‘venereal peril’ that had little to do with the colony itself.Footnote 51 In so doing, they ignored the ways in which the spread of sexually transmitted diseases (gonorrhea and syphilis) was entangled with a wider political economy of colonial forced labor, taxation, and migration.Footnote 52
Historical insights such as these call into question biomedical researchers' use of computer simulations. De Sousa and his colleagues modeled the spread of HIV in Kinshasa in 1919, 1928, and 1958, using parameters extracted from Yaoundé sex worker data, which came from an epidemiological study conducted in four African cities in 2000–01. ‘Commercial sex workers’ included in their 1919 model, for instance, engaged in an average of 600 ‘sex acts’ per year – a highly presentist assumption, premised on already-unreliable evidence about reported sexual behavior. Such models have no real historical significance: pandemic HIV history requires more meticulous attention to the changing nature of these intimate domestic, affective, and sexual relations between women and their male customers. Fine-grained historical insights might illuminate why there was no noticeable HIV epidemic between the 1920s and the 1960s, and raise the possibility that a later emergence of serial prostitution (in the 1940s or 1950s) would more likely have contributed to heightened HIV transmission.
A broader analysis of the role of mobility in epidemic emergence is also necessary. De Sousa et al.'s research neglects the connection between Leopoldville and Brazzaville, including cross-river mobility of sex workers. Indeed, de Sousa has contended that although HIV emerged in Leopoldville in the 1920s, it only reached Brazzaville in the 1970s. In this case, the simulation models led to an implausible conclusion that unprecedented conditions in Leopoldville enabled the sexual spread of the virus only within the city, but not across the river.Footnote 53
Some filles publiques escaped Leopoldville and colonial strictures against prostitution to practice their work elsewhere in the colony; many European employers hired African maids to perform mundane household and to provide sexual services.Footnote 54 The Force Publique, an African police force created by Leopold II as an instrument of terror and coercion under his ‘red rubber’ scheme, was routinely dispatched to remote areas. There, they often used rape and other sexual abuses as a weapon against recalcitrant communities and villagers. Spreading terror among civilians, the Force Publique also likely disseminated venereal diseases in remote communities.Footnote 55
Finally, attention to cultural change reflected in other kinds of sources illuminates Kinshasa's gender revolution in the 1940s and 1950s – and offers new clues to possible early HIV mortality patterns. Didier Gondola's studies of 1940s and 1950s Kinshasa suggest that young free women (femmes libres or ndoumba in Lingala), empowered by their newfound economic and social status, subverted existing gender norms and patterns that largely favored men.Footnote 56 Contemporary popular lyrics and newspapers offer insight into these new femmes libres, who reveled in fashion, fête, and friendship through recreational associations that bear suggestive names: ‘la violette’, ‘la rose’, and ‘diamant’. These women could be seen, decked out in the latest fashion in myriad beer halls, nightclubs, and flamingos that sprouted up throughout African townships. It was rumored that they changed male partners as often as they would their colorful pagnes (wraparound skirts). For all their youthful exuberance, success, and swagger, the femmes libres entertained a heightened anticipation for death; popular press and music suggest that a lifestyle of multiple partners had exposed them to an epidemic that depleted their ranks. They lived their lives as if death was lurking around the corner, and planned accordingly. Journalist Jean-Jacques Kande wrote in 1957, ‘A popular young woman in Leopoldville shouldn't have fewer than twenty buses to accompany her hearse to her final resting place. Otherwise she brings shame on her relatives and female friends.’Footnote 57
Medical campaigns, blood transfusions, and unsterile medical procedures
One significant achievement of recent scholarship on HIV beginnings is the demonstration that mass medical campaigns contributed to HIV's initial spread. Following Marx and Drucker, Jacques Pépin and his collaborators documented in southern Cameroon, south-western Central African Republic, and Gabon how unsterile medical procedures during colonial public health interventions between 1910 and 1960 likely accelerated HIV transmission in African populations. They based their conclusions on the epidemiology of Hepatitis C virus (HCV), a pathogen exclusively transmitted through contaminated blood exposure. Because HCV carriers can live for decades with chronic infection, HCV prevalence constitutes an indirect marker of past procedures at risk for HIV transmission by blood, including medical interventions.Footnote 58 Hence, the current HCV epidemic in Cameroon, which mostly affects elderly people in rural areas, can be interpreted as evidence of a major event of iatrogenic transmission of blood borne viruses between 1920 and 1960. This event may well have facilitated HIV spread, but because HIV kills its victims more rapidly than HCV, it left no long-term survivors, and thus has gone undetected in recent studies. Similar studies are under way in the Democratic Republic of Congo.
Colonial archives and a literature on colonial medicine have been crucial to this work, correlating current patterns of infection with past medical interventions. Pépin's research systematically documents how the scale, intensity, and nature of the campaigns against endemic diseases (especially yaws, syphilis, and trypanosomiasis) in Central Africa heightened the risk of transmitting HIV. It has shifted debates about AIDS origins away from refuting Edward Hooper's hypothesis concerning the putative role of oral polio vaccines; instead, it takes seriously the question of iatrogenic transmission and evaluates it using accepted virological evidence.
Recent historical research on the contribution of blood transfusion to the early HIV epidemic demonstrates the value of attention to new sources, everyday medical practices, and multi-causal factors in emergence. Researchers consistently overlooked the role of blood transfusion in HIV emergence until William Schneider and Ernest Drucker published a first overview in 2006.Footnote 59 Since then, several analysts have accepted transfusion as yet another example of iatrogenesis through contaminated injections.Footnote 60
But blood transfusion in Africa warrants further attention, both for its role in expanding HIV-1M transmission and in adapting simian viruses into human ones. Blood transfusion is a highly efficient means of transmitting disease – nearly 100 per cent, compared to sexual transmission or unsterile needles (ranging from 0·001 per cent to 0·3 per cent from contaminated persons, depending on their viral load).Footnote 61 Indeed, no twentieth-century medical development permitted disease transmission more efficiently than blood transfusion. Conducted in sub-Saharan Africa as early as the 1920s and practiced regularly in some colonies (including Belgian Congo), blood transfusion in Africa began concurrently with HIV-1M's earliest adaptation. It likely facilitated the HIV epidemic, by transmitting more contagious strains, and almost certainly by spreading the epidemic in the 1960s and 1970s.Footnote 62
Documenting the scope of blood transfusion has required exploring new sources, including documents detailing laboratory testing or patient and other hospital records. Although some physicians reported the earliest transfusions in journals,Footnote 63 standardized hospital reporting of transfusions did not occur until the 1950s, so maintaining transfusion records depended on individual hospital practice. Whether recorded or not, several trends facilitated the spread of transfusions. First, transfusions became progressively easier to practice during the first half of the twentieth century. Equipment (syringes) was readily available, the ‘medicine’ (human blood) was easily accessible, and patients generally accepted transfusion. The limiting factor was doctors with knowledge of transfusion, but as training grew more common in Europe and more doctors joined colonial health services, the procedure became more widely used. The growth of hospitals following the First and Second World Wars also expanded the practice. Even before the formal establishment of blood banks in Belgian Congo, donors on demand provided blood to a wide range of patients, from those with pneumonia, to those undergoing surgery for accidents or experiencing difficult obstetrical deliveries, to anemic infants.Footnote 64 By the 1950s, blood transfusions were widely used in Leopoldville and other Belgian Congo centers.Footnote 65
The exact contribution of blood transfusion to HIV transmission remains difficult to estimate. Until recently in Africa, men between the ages of 18 and 40 made up the overwhelming majority of donors. Men with serious injuries also received many of the transfusions. Few records exist to indicate the likelihood of a transfusion recipient subsequently donating blood, but it is plausible. Adult males receiving blood transfusions were encouraged to become donors, and they in turn would inspire others to donate.Footnote 66 The practice of collecting blood from groups such as prisoners, soldiers, and older male school children increased the likelihood of recipients themselves later donating blood.
These observations assume the existence of a fully adapted, epidemically contagious virus. But several decades elapsed between the early 1920s (the estimated date of HIV-1M's earliest ancestor) and the detection of an epidemic in the early 1980s. Perhaps partially adapted HIVs were transmitted at low rates until new circumstances permitted epidemic transmission, including the adaptation of an epidemic form of the virus. The timing suggests that the growth of transfusion played a role in the adaptation process. Moreover, the place and estimated times of the earliest forms of HIV-2 viruses in Western Africa occurred in the 1940s – when blood transfusion was already practiced throughout sub-Saharan Africa.Footnote 67
Transfusion alone, however, does not likely account for the HIV-1M virus's adaptation to human transmission, since it remained relatively infrequent in the 1920s and 1930s in Central Africa. In addition, other means of viral transmission were simultaneously increasing: migration to urban and other work centers expanded sexual relations, and large-scale injection campaigns using inadequately sterilized needles began in the 1920s and escalated in the 1940s.Footnote 68 Hence, as with the expansion of the epidemic itself, HIV-1M's adaptation to human beings may have resulted from a combination of all these modes of transmission. The process may have occurred over the course of years, even decades. So too may have the later HIV-2 adaptations arisen from an entirely different combination of these developments. In any case, both scenarios contrast sharply with the ‘smoking gun’ explanation that many biomedical researchers have sought.
The upshot of historical work on blood transfusions and medical campaigns is that it shifts explanations away from vague allusions to urbanization and from an obsession with African ‘behavioral changes’ (especially sexual) associated with colonization or decolonization.Footnote 69 It enables us to locate medical technology and biopolitics at the core of the HIV emergence narrative, and to stress that past and present HIV/AIDS must be understood within a wider political economy of disease.Footnote 70
Such work also inspires new research questions about the material culture of colonial medicine and the management of risks associated with drug toxicity, unsterile injection, or transfusions.Footnote 71 Iatrogenesis occurred as the consequence of debates and choices that involved colonial experts, as well as African nurses, auxiliaries, and patients, and as produced by deliberate, rationalized risk-taking and material constraints.Footnote 72 Frequent and massive accidents led to controversies about the safety and efficiency of disease campaigns.Footnote 73 Historians need to investigate such controversies: how they were followed (or not) by changing procedures and ethics of the campaign; and how they echoed (or not) European debates about the hazards of modern biomedicine.
Research on the contribution of medical interventions to HIV emergence – and their limitations – should inspire further historical investigation. Spectacular interventions such as Eugène Jamot's trypanosomiasis campaigns in Cameroon obscure the role of more dispersed forms of daily hospital, missionary, dispensary, or informal health care.Footnote 74 Historians might also investigate the consequences of post-independence transformations in health care infrastructures, professions, and technologies. Older retrospective epidemiological investigations would thus give way to newer explorations of urban- and rural-based material routines, investments, and lay experiences of daily biomedical practices, and, their roles in shaping the present HIV epidemic.
CONCLUSION
There exists an unusual opportunity for historians of Africa to engage with biomedical scientists in order to rethink social, political economic, and environmental histories of Africa, and to contribute to developing investigations and questions around HIV/AIDS. We can draw crucial questions and evidence from virology, epidemiology, and evolutionary biology, and, at the same time, contribute valuable insights on the beginnings and expansion of HIV-1, HIV-2, and, more broadly, ‘emerging diseases’. Without the new tools of virology and evolutionary biology, there would be no ‘origins of HIV’ debate. Historians of Africa need to take stock of the extraordinary data assembled by practitioners of these sub-disciplines; the growing archive of viral sequences constitutes a new source of viral archeological data that can contribute to our understandings of the social history of Africa and its place in global history.
At the same time, historians can bring their expertise in uncovering and interpreting a wider range of sources to shed light on the multiple and contingent changes contributing to emergence. Expanding the temporal, political, economic, and social contexts and exploring daily living practices and conditions, and routine medical care might assist in understanding better how HIV and other diseases emerged.Footnote 75 What difference would writing more complex, nuanced comparative histories of HIV emergence make? The potential contributions are several. First, critical historical perspectives can help concretely to underscore the inappropriate assumptions in computer simulations of outbreak and emergence. We have argued, for instance, that modeling past HIV emergence based on contemporary, questionable suppositions about sexual contacts renders meaningless conclusions. At the very least, our active reading and critiques can convince modelers, evolutionary biologists, epidemiologists, and virologists of the substantial limitations of exercises premised on such dubious assumptions.
Second, our attention to new kinds of sources, to everyday practices of livelihood, medical interventions and care, mobility, and changing sexual relations, and to comparative perspectives can help to derail the narrow focus on ‘origins’ and ‘smoking guns’. As James Webb has argued for in his contribution to this JAH Forum, we are advocating a genuinely multidisciplinary approach to the questions of disease outbreak and emergence. Such an approach necessitates a real integration of the multiple optics through which history, social sciences, virology, epidemiology, and evolutionary biology evaluate this historical problem. More concretely, we want to show clearly to our biomedical colleagues that history is not just about dramatic events, but also the larger processes, longer-term continuities, and incremental changes in human relations and practices that clearly contributed to HIV emergence and may figure in the emergence of other new diseases.
We are also witnessing an unprecedented biomedical interest in what historical analyses can contribute to questions about HIV beginnings and expansion. As historians, we need to show where evidentiary misinterpretations, a lack of comparative perspective, or an undue focus on particular sources or events, produce misleading conclusions.Footnote 76 We should also vigorously defend our own cognitive strategies and standards of proof, and our disciplinary use of narrative and what Carlo Ginzburg has called ‘indiciary’ knowledge, a way of knowing that uses traces of evidence as metonyms for accessing the past.Footnote 77
We end here with a concrete example that illustrates the value of phylogenetic data for historians, as well as the potential relevance of historical reflection about HIV emergence for public health. In 2007, Gilbert et al. used phylogenetic data to reconstruct the geographic sequence and time line for the pandemic emergence of HIV/AIDS outside of Africa.Footnote 78 The team showed that Haiti served as an epidemic transit point between Congo and the rest of the world. They also found that neither virus mutations nor the migration of human beings had been limiting factors in the global spread of HIV. Despite intense exchanges between Congo, Haiti, and the United States, the current HIV pandemic was provoked by a single introduction of the virus from Congo to Haiti, and then from Haiti to the United States. As a consequence, in Haiti and the United States, the HIV epidemic was initially caused by a genetically homogenous population of viruses that began from that single introduction. The pandemic caused by HIV-1 M subtype B is the product of this series of contingent events. More importantly, they made clear that the initial spread of HIV beyond Africa was limited primarily by the poor transmissibility of HIV, and thus by the very low chance that any infected individual would find him- or herself in a human subpopulation with sufficient epidemic potential. This phylogenetic reconstruction revealed that the existence of discrete, local, and highly favorable conditions enabled HIV to overcome epidemiological bottlenecks and thus to spread worldwide.Footnote 79
While explaining the nature of these specific historical conditions was beyond the scope of the team's work, the very recognition that these conditions gave rise to and shaped the global HIV expansion offers a wealth of questions that historians could tackle. It also offers a major lesson for public health today. Current global health doxa asserts that present-day ‘globalization’, characterized by rapid air transport and implicitly pathologized migration, is a major driver of new disease emergence. The historical ‘success’ of HIV as an emerging pathogen indicates a significant flaw in this ‘emerging diseases worldview’.Footnote 80 The focus of current global health efforts on molecular surveillance and on real-time tracking of emerging pathogens misses the key factor in disease emergence and the lessons offered by HIV. Specific historical and local ecologies – including medical technologies, patterns of gender and sexual relations, as well as broader structural factors – primarily shaped the geography and temporality of the HIV epidemic, not viral fitness or migration pathways. Pandemic preparedness efforts would do well to refocus their attention on socioeconomic and political conditions and processes, for example, by expanding investment in basic primary and hospital health care services and medical training.Footnote 81 Investment in health infrastructure and personnel would be at least as useful in preventing outbreaks as surveillance systems. These investments could help to ameliorate low-resource medical structures, which constitute one fertile terrain for human pathogen emergence, but more critically, they would begin to redress the deplorable inequities in access to basic health care on the African continent.
