The collision of a set of otherwise innocuous circumstances can lead to an epidemic that was the worst in the history of the city. In 1793 Philadelphia had a wet spring, leaving behind swamps and stagnant pools that became breeding grounds for mosquitoes. At the same time, refugees who carried the yellow fever virus were fleeing to Philadelphia from the Revolution in Santo Domingo (now Haiti). At some point in the summer if 1793, a female aedes aegypti (the mosquito carrier of yellow fever) bit an infected refugee. When this mosquito later bit a Philadelphian, she passed along the deadly yellow fever virus.

On August 17, 1793, Philadelphia's renowned Dr. Benjamin Rush conferred with two other local doctors about a disease that he had observed over the last two weeks. Symptoms included fever, nausea, skin eruptions, black vomit, incontinence, jaundice-and finally death. In those early weeks of the epidemic the disease centered on the waterfront district. Rush and his fellow physicians diagnosed the disease as yellow fever and suspected the cause to be putrefied air-miasma-from a spoiled cargo of Santo Domingo coffee that had been dumped on the docks.

Rush believed that the seriousness of the outbreak called for drastic purging and bleeding-removing as much as four-fifth of an infected person's blood. Dr. Currie and his followers prescribed milder treatments.

From mid-August to late September, over 600 more Philadelphians died from the fever. Half the population fled the city. Those who remained lived in constant dread of falling ill. Philadelphian Mathew Carey wrote later: "Acquaintances and friends avoided each other on the streets, and only signified their regard by a cold nod. The old custom of shaking hands fell into such general disuse that many were affronted at even the offer of a hand." In an effort to stem the spread of the virus, the city's hospital and the almshouse refused entry to yellow fever victims. A special fever hospital was set up at Andrew Hamilton's estate on Bush Hill, organized by a French physician, Dr. Deveze, familiar with yellow fever.

Meanwhile, Dr. Rush persuaded prominent African-American clergymen Absolom Jones and Richard Allen that Blacks were immune to the fever (as many believed at the time) and could safely assist in care of the victims. Encouraged by the ministers, African Americans worked as nurses and as carters of dead bodies during the epidemic. But the immunity was an illusion; soon African American Philadelphians were also dying in great numbers.

By November, when the epidemic receded, probably 5000 Philadelphians had died, more than 10% of population. The next summer yellow fever returned, but not as severely, and also in 1796 and 1797. Another severe epidemic came in 1798, killing 1292 Philadelphians. By this time, the advantages of flight were clear. At the peak of the 1798 epidemic all but 7000 residents had left the city.

For the Adult Readers:
Powell, J.H.
Bring Out Your Dead: The Great Plague of Yellow Fever in Philadelphia in 1793
Philadelphia: University of Pennsylvania Press, 1993

Young Readers:
Anderson, Laurie Halse.
Fever 1793
New York: Simon & Schuster Books for Young Readers, 2000
Fever 1793, a fictional account of the 1793 yellow fever epidemic in Philadelphia, is an excellent book for readers of all ages. Using primary source information on the epidemic, Anderson illuminates the controversy surrounding Rush's bleeding techniques versus French methods; she also discusses the overall impact of the epidemic on the city.