What the Yellow Fever Epidemic of 1793 Revealed About America
Yellow fever is a brutal disease that afflicted much of the United States in the eighteenth and nineteenth centuries; it still kills tens of thousands every year in some parts of the world.
In 1793, a particularly bad outbreak killed 10% of Philadelphia’s population, and caused perhaps half the city to flee. The city’s response to the disease exposed some of America’s most intense and enduring fault lines, especially racial prejudice and political partisanship.
Cotton Mather, a Puritan leader who live about a century before the 1793 epidemic, described the symptoms of yellow fever as “turning yellow then vomiting and bleeding every way.” Victims contract a fever, nausea, and aches. In severe cases, people’s livers and kidneys stop functioning (the liver damage causes the yellow skin) and there is bleeding in the patient’s digestive system.
Over half of those who enter this stage die of the disease, even today. In the 1700s, people did not understand the sources of the disease. The Aedes aegypti mosquito’s role in transmitting the virus was not understood until the early 1900s; in the 1790s, people thought that miasma — basically, filthy air — was the vector that transmitted the disease.