Yellow Fever, Race, and Ecology in Nineteenth-Century New Orleans by Urmi Engineer Willoughby (review)

Perhaps the most important lesson from Urmi Engineer Willoughby's book is that human activity drives the spread of mosquito-borne illnesses. Willoughby persuasively argues that, in the case of nineteenth-century New Orleans and the Atlantic world more broadly, human migration, both forced and free; urban development; and the growth of the sugar industry created conditions ideal for yellow fever. Repeated outbreaks of the fever over the course of the nineteenth century stemmed from human-induced ecological change, and both medical and popular responses to these epidemics reflected changing ideas about race.

The strongest parts of the book explain the ways human-induced ecological change invited yellow fever epidemics. These changes can be grouped into three rough categories: the creation of sugar plantations, landscape alterations, and human migration. Sugar plantations, which expanded in Louisiana after the Haitian Revolution, created conditions especially favorable to A. aegypti, the species of mosquito that transmits the disease. Moreover, urban and rural landscape alterations created mosquito habitats. Water management projects facilitated the growth of mosquito populations, while deforestation reduced the number of natural predators.

Willoughby argues that these activities spurred an increase in mosquito-borne illnesses not only in New Orleans but also in West Africa, the Caribbean, and Latin America. Although much of the existing scholarship on yellow fever in the early republic focuses on Philadelphia, Willoughby makes a compelling case for the importance of studying New Orleans, in part because of the region's migration patterns. Because survivors of yellow fever develop a lifelong immunity to it, Louisiana residents tended to have acquired immunities to the illness. Thus in early-nineteenth-century New Orleans, both physicians and other residents thought of yellow fever as a "stranger's disease," one afflicting recent migrants to a region in which it was endemic (p. 53). Waves of European immigration brought susceptible populations to the area, allowing yellow fever to thrive. The slave trade also spread yellow fever around the Atlantic world, and New Orleans's location as a port city meant that inhabitants were consistently exposed to the disease.

As an increasingly binary system of racial classification took hold during the mid-to-late nineteenth century, both popular and medical perceptions of the disease began to shift. Willoughby argues that physicians and others no longer believed that yellow fever afflicted all strangers but instead started to imagine racial divisions in susceptibility. Willoughby is unclear about exactly when this shift occurred, stating that medical authorities began advocating theories of "race-based resistance" in the 1830s and 1840s and that they "emphasized race as a factor in determining yellow fever resistance" during the 1850s (pp. 64, 85). These views "gained widespread acceptance" after an epidemic in 1853, but decades later, the epidemic of 1878 also "marked a period of shifting views about racial immunity," as physicians "emphasized race" as a crucial factor (pp. 86, 120, 121). While these various dates likely reflect an uneven transformation in both medical and popular thought, they can be confusing.

Willoughby presents substantial evidence demonstrating black susceptibility to yellow fever, both in New Orleans and across the Atlantic world. These documents, drawn from medical texts, journals, and other reports, support her argument that theories of race-based resistance were entirely imagined and were, in large part, driven by racism. In fact, Willoughby is so thorough at debunking race-based theories that evidence demonstrating the prevalence of these theories—which are crucial to her larger claims that physicians advocated these ideas in the face of evidence to the contrary—is thin. While it is not difficult to believe that physicians promoted racial theories, more examples showing their pervasiveness would strengthen Willoughby's argument.

Finally, Willoughby links the spread of mosquito-borne illnesses in the twentieth century to U.S. imperialist projects. She explains how increased sanitation measures in the wake of germ theory lowered the number of yellow fever outbreaks in...