Maladies of Empire: How Colonialism, Slavery, and War Transformed MedicineJim DownsHarvard University Press, 2021Applying the study of history to medicine can often be uncomfortable, so I had some trepidation as I picked up Maladies of Empire: How Colonialism, Slavery, and War Transformed Medicine by Jim Downs. The title certainly grabbed my attention; did these events really transform medicine? After reading this provocative book, it is hard to argue otherwise.With meticulous research and compelling evidence, Downs demonstrates how colonialism, slavery, and war enabled physicians to study the spread of disease among captive populations, contributing to the development of the emerging field of epidemiology. Between 1756 and 1866, these history-shaping forces created bureaucracies that collected information, analyzed data, and issued reports, allowing physicians to develop theories on the cause, spread, and prevention of infectious disease.Downs skillfully brings together seemingly disparate events, arguing that the international slave trade, the expansion of colonialism, the Crimean War, the US Civil War, and the travels of Muslim pilgrims—topics isolated from each other until now—changed the medical profession's understanding of disease transmission, significantly shaping the study of epidemiology. More importantly, he emphasizes how the people who were the subjects of study—the enslaved, the imprisoned, the poor, and the dispossessed—have been largely erased from history. Downs brings these people to the forefront, telling their stories, documenting their lives, their sufferings, and often their deaths, as best one can with a limited historical record.Maladies of Empire offers a history lesson on the cost of medical progress. When British soldiers died while packed into a tiny Calcutta jail in 1756, the infamous “Black Hole of Calcutta,” researchers drew conclusions on the dangers of crowded spaces and the importance of fresh air. Alternately, women washing the linens of passengers on ships from plague-infected countries in the 1830s unknowingly became the subject of studies. Passengers traveling from North Africa and the Middle East were forced to quarantine on the island of Malta before continuing to Europe. Researchers discovered that the laundresses did not contract the disease, leading some to question contagion theory and the need for quarantine laws.The slave trade enabled physicians to study how long humans could live without food, and how placing large numbers of enslaved people in crowded and unsanitary conditions in the bottom of ships, which then led to medical disorders, provided valuable information for researchers.Downs details the work of “the Lady of the Lamp,” Florence Nightingale, known by most for her work providing nursing care to wounded soldiers during the Crimean War. Nightingale studied the spread of disease in India, a place she never visited, by collecting reports, collaborating with investigators, publishing papers, and developing theories, making her a pioneer in the use of statistics to study disease. That Nightingale's significant contributions to epidemiology have been ignored is likely due, Downs contends, to the fact she was a woman and a nurse in a field dominated by white European men.During the US Civil War, facing smallpox vaccine shortages, doctors injected lymph into the arms of enslaved children, then used the children's bodies to harvest vaccine matter for use in soldiers. Southern doctors experimented with vaccines on Union soldiers at the infamous Andersonville prison, causing the deaths of men who were suffering from scurvy. Doctors studying Black Union troops began classifying racial differences as key factors in examining the spread of disease. Unsurprisingly, this led to the development of racist theories that persisted for decades.Ultimately, Downs contends that part of the origin story of epidemiology has been largely ignored because it resulted from studying people who suffered from war, enslavement, and imperialism, most of whom were people of color. Downs' stated purpose in Maladies of Empire is to shift the focus from the physicians to the people they studied, whose suffering and death contributed to foundational medical knowledge, but whose identities have been erased from the medical record. Downs believes it is far past time for these oppressed groups of humanity to reclaim their rightful place in history.While I find the history of medicine, given its generally grisly track record, to be anything but pleasant—the words ghastly and abhorrent also often come to mind—understanding how the medical profession treated certain underprivileged—to put it mildly—groups of people in the past can, as witnessed by this insightful work by Jim Downs, perhaps, raise awareness of how unconscious racial and ethnic biases contribute to health inequities among marginalized groups today.