Malaria

An Old World parasitic blood disease spread by mosquitoes, malaria extracted a fatal and mysterious toll on human life in colonial America. Undiagnosed until the 19th century, most colonists referred to its feverlike symptoms as the “ague,” and they believed the sickness emanated from miasmic air and impure water.

Initially carried to Mexico and the Caribbean by Spanish explorers and soldiers in the early 16th century, malaria thrived in the tropical areas of the Americas. The parasite quickly established a colonial regime of its own, expanding in advance of European settlers along Native American trade routes that followed mosquito-prone streams north into the Sonoran Desert. In British America, malaria arrived at least as early as the Jamestown expedition, and, by the 18th century, the disease had staked its claim along broad swaths of the Atlantic and Gulf Coasts.

Malaria flourished particularly in the wet, crowded environs of the southern colonies’ low-lying coastal plantations. Lethal on its own, the parasite also weakened human immunities to other infectious diseases. Even though sickle-cell anemia afforded them some resistance to the disease, African and African-American slaves, who often experienced chronic fatigue and malnourishment, suffered from malaria. Realizing a connection between the ague and swampy coastal plantations, most wealthy whites moved to second homes in inland cities to escape summer outbreaks. Those who could afford it also bought “the bark,” an imported antimalarial agent derived from the South American cinchona plant. Although unconfined to any single class, malaria often struck the poor harder than the rich since the former could not afford to escape infected areas.

Further reading: Alfred Crosby, Ecological Emperial-is-m: The Biological Expansion of Europe, 900-1900 (Cambridge: Cambridge University Press, 1986).

—Michael Wise