As the COVID-19 pandemic swept the globe in 2020, it left in its wake the near-paralysis of many hospital systems, unprepared and unequipped for the waves of illness and death that suddenly overwhelmed capacities for treatment that were after all at best only palliative care, since for this deadly new virus there was neither a cure nor a clear route to prevention. Overnight, epidemiologists—scrambling for answers or even just clues—became the most critically significant members of the public health community, even if their informed voices were often shouted down by the shriller ones of media pundits and political hacks.

Meanwhile, data collection began in earnest and the number of data dashboards swelled. In the analytical process, the first stop was identifying the quality of the data and the disparities in how data was collected. Was it true, as some suggested, that a disproportionate number of African Americans were dying from COVID? At first, there was no way to know since some states were not collecting data broken down by this kind of specific demographic. Data collection eventually became more standardized, more precise, and more reliable, serving as a key ingredient to combat the spread of this highly contagious virus, as well as one of the elements that guided the development of vaccines.  Even so, dubious data and questionable studies too often took center stage both at political rallies and in the media circus that echoed a growing polarization that had one side denouncing masks, resisting vaccination, and touting sideshow magic bullets like Ivermectin. But talking heads and captive audiences aside, masks reduce infection, vaccines are effective, and dosing with Ivermectin is a scam. How do we know that? Data. Mostly due to data. Certainly, other key parts of the mix include scientists, medical professionals, case studies, and peer reviewed papers, but data—first collected and then analyzed—is the gold standard, not only for COVID but for all disease treatment and prevention.

But it wasn’t always that way.

In the beginning, there was no such thing as epidemiology. Disease causes and treatments were anecdotal, mystical, or speculative.  Much of the progress in science and medicine that was the legacy of the classical world had long been lost to the west. The dawn of modern epidemiology rose above a horizon constructed of data painstakingly collected and compiled and subsequently analyzed. In fact, certain aspects of the origins of epidemiology were to run concurrent with the evolution of statistical analysis. In the early days, as the reader comes to learn in this brilliant and groundbreaking 2021 work by historian Jim Downs, Maladies of Empire: How Colonialism, Slavery, and War Transformed Medicine, the bulk of the initial data was derived from unlikely and unwilling participants who existed at the very margins: the enslaved, the imprisoned, the war-wounded, and the destitute condemned to the squalor of public hospitals. Their identities are mostly forgotten, or were never recorded in the first place, but yet collectively the data harvested from them was to provide the skeletal framework for the foundation of modern medicine.

In a remarkable achievement that could hardly be more relevant today, the author cleverly locates Maladies of Empire at the intersection of history and medicine, where data collection from unexpected and all too frequently wretched subjects comes to form the very basis of epidemiology itself. It is these early stories that send shudders to a modern audience. Nearly everyone is familiar with the wrenching 1787 diagram of the lower deck of the slave ship Brookes, where more than four hundred fifty enslaved human beings were packed like sardines for a months-long voyage, which became an emblem for the British antislavery movement. But, as Downs points out, few are aware that the sketch can be traced to the work of British naval surgeon Dr. Thomas Trotter, one of the first to recognize that poor ventilation in crowded conditions results in a lack of oxygen that breeds disease and death. His observations also led to a better understanding of how to prevent scurvy, a frequent cause of higher mortality rates among the seaborne citrus-deprived. Trotter himself was appalled by the conditions he encountered on the Brookes, and testified to this before the House of Commons. But that was hardly the case for many of his peers, and certainly not for the owners of slave ships, who looked past the moral dilemmas of a Trotter while exceedingly grateful for his insights; after all, the goal was keep larger quantities of their human cargo alive in order to turn greater profits. Dead slaves lack market value.

A little more than three decades prior to Trotter’s testimony, the critical need for ventilation was documented by another physician in the wake of the confinement of British soldiers in the infamous “Black Hole of Calcutta” during the revolution in Bengal, which resulted in the death by suffocation of the majority of the captives.  Downs makes the point that one of the unintended consequences of colonialism was that for early actors in the medical arena it served to vastly extend the theater of observation of the disease-afflicted to a virtually global stage that hosted the byproducts of colonialism: war, subjugated peoples, the slave trade, military hospitals and prisons. But it turns out that the starring roles belong less to the doctors and nurses that receive top billing in the history books than to the mostly uncredited bit players removed from the spotlight: the largely helpless and disadvantaged patients whose symptoms and outcomes were observed and cataloged, whose anonymous suffering translated into critical data that collectively advanced the emerging science of epidemiology.

Traditionally, history texts rarely showcased notable women, but one prominent exception was Florence Nightingale, frequently extolled for her role as a nurse during the Crimean War. But as underscored in Maladies of Empire, Nightingale’s real if often overlooked legacy was as a kind of disease statistician through her painstaking data collection and analysis—the very basis for epidemiology that was generally credited to white men rather than to “women working in makeshift hospitals.” [p111] But it was the poor outcomes for patients typically subjected to deplorable conditions in these makeshift military hospitals—which Nightingale assiduously observed and recorded—that drew attention to similarly appalling environments in civilian hospitals in England and the United States, which led to a studied analysis that eventually established systematic evidence for the causes, spread, and treatment of disease.

The conclusions these early epidemiologists reached were not always accurate. In fact, they were frequently wrong. But Downs emphasizes that what was significant was the development of the proper analytical framework. In these days prior to the revolutionary development of germ theory, notions on how to improve survival rates of the stricken put forward by Nightingale and others were controversial and often contradictory. Was the best course quarantine, a frequent resort? Or would improving the sickbed conditions, as Nightingale advocated, lead to better outcomes? Unaware of the role of germs in contagion, evidence could be both inconclusive and inconsistent, and competing ideas could each be partly right. After all, regardless of how disease spread, cleaner and better ventilated facilities might lead to lower mortality rates. Nightingale stubbornly resisted germ theory, even as it was widely adopted, but after it won her grudging acceptance, she continued to promote more sanitary hospital conditions to improve survival rates. Still, epidemiologists faced difficult challenges with diseases that did not conform to familiar patterns, such as cholera, spread by a tainted water supply, and yellow fever, a mosquito-borne pathogen.

In the early days, as noted, European observers collected data from slave ships, yet it never occurred to them that because their human subjects were black such evidence was not applicable to the white population. But epidemiology took a surprisingly different course in the United States, where race has long proved to be a defining element.  Of the more than six hundred thousand who lost their lives during the American Civil War, about two-thirds were felled not by bullets but by disease. The United States Sanitary Commission (USSC) was established in an attempt to ameliorate these dreadful outcomes, but its achievements on one hand were undermined on the other by an obsession with race, even going so far as the sending out to “. . . military doctors a questionnaire, ‘The Physiological Status of the Negro,’ whose questions were based on the belief that Black soldiers were innately different from white soldiers . . . The questionnaire also distinguished gradations of color among Black soldiers, asking doctors to compare how ‘pure Negroes’ differed from people of ‘mixed races’ and to describe ‘the effects of amalgamation on the vital endurance and vigor of the offspring.’” With its imprimatur of governmental authority, the USSC officially championed scientific racism, with profound and long-term social, political, and economic consequences for African Americans. [p134-35]

Some of these notions can be traced back to the antebellum musings of Alabama surgeon Josiah Nott—made famous after the war when he correctly connected mosquitoes to the etiology of Yellow Fever—who asserted that blacks and whites were members of separate species whose mixed-race offspring he deemed “hybrids” who were “physiologically inferior.” Nott believed that all three of these distinct “types” responded differently to disease. [p124-25] His was but one manifestation of the once widespread pseudoscience of physiognomy that alleged black inferiority in order to justify first slavery and later second-class citizenship. Such ideas persisted for far too long, and although scientific racism still endures on the alt-right, it has been thoroughly discredited by actual scientists.  It turns out that a larger percentage of African Americans did indeed succumb to death in the still ongoing COVID pandemic, but this has been shown to be due to factors of socioeconomic status and lack of access to healthcare, not genetics.

Still, although deemed inferior, enslaved blacks also proved useful when convenient. The author argues that “… enslaved children were most likely used as the primary source of [smallpox] vaccine matter in the Civil War South,” despite the danger of infection in harvesting lymph from human subjects in order to vaccinate Confederate soldiers in the field. In yet one more reminder of the moral turpitude that defined the south’s “peculiar institution,” the subjects also included infants whose resulting scar or pit, Downs points out,    “. . . would last a lifetime, indelibly marking a deliberate infection of war and bondage. Few, if any, knew that the scars and pit marks actually disclosed the infant’s first form of enslaved labor, an assignment that did not make it into the ledger books or the plantation records.” [p141-42]

Tragically, this episode was hardly an anomaly, and unethical medical practices involving blacks did not end with Appomattox. The infamous “Tuskegee Syphilis Study” that observed but failed to offer treatment to the nearly four hundred black men recruited without informed consent ran for forty years and was not terminated until 1972! One of the chief reasons for COVID vaccine hesitancy among African Americans has been identified as a distrust of a medical community that historically has either victimized or marginalized them.

Maladies of Empire is a well-written, highly readable book suitable to a scholarly as well as popular audience, and clearly represents a magnificent contribution to the historiography. But it is hardly only for students of history. Instead, it rightly belongs on the shelf of every medical professional practicing today—especially epidemiologists!