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A Malignant Tale (Yellow Fever, 1793 Epidemic) 

Mosquito Time Travel: A Malignant Tale

Ali Rospond, Museum Education Coordinator, American Philosophical Society. 

Imagine Philadelphia in 1793. The growing city had a population of 50,000 of which around 2,000 were black Philadelphians, 310 of whom were enslaved. The city was the center of government, trade, science, and medicine. The country was still trying to find its footing; the U.S. Constitution was signed only six years prior in 1787. Then, tragedy strikes as yellow fever breaks out in 1793, killing 5,000 people, 10% of Philadelphia’s population. 

Philadelphia’s doctors were debating throughout this period about the best treatment against yellow fever as the population grappled with their own theories. People didn’t know if the illness was contagious or not. Some had wild theories as to the origin, like miasma (bad stuff in the air) or spoiled coffee beans on the dock. Today we know that yellow fever is transmitted through the bite of an infected mosquito, specifically the Aedes aegypti. Yellow fever received its name from the effects it has on the body with the development of a high fever and jaundice. People in the 1700s were unsure as to what caused yellow fever and looked to doctors like Benjamin Rush for guidance in combating it. 

Dr. Benjamin Rush was a proponent of medical bloodletting: bleeding a patient to balance out the fluids in the body. This matched the 18th-century belief that illness was the result of an imbalance of “good” and “bad” bodily fluids. To get rid of the bad blood, they would bleed a person, to rid the body of the bad stuff and in hopes that the body would produce more good blood. As the epidemic progressed, Rush saw that there were too many sick people and not enough doctors and nurses to take care of them. Rush turned to the Free African Society for help in combating the epidemic. At the time Rush believed (incorrectly) that all African Americans in Philadelphia were immune to yellow fever. This theory led him to the Free African Society and to ask for their aid in nursing, body removal, and burial. He assured them that they would not contract yellow fever. 

The Free African Society was a mutual aid society that helped develop leaders in African American communities, as well as help newly freed African Americans. This effort to bring in and coordinate volunteers was headed by Absalom Jones, Richard Allen, and William Gray. During the epidemic, they helped identify nurse trainees, kept the streets clean, collected the bodies of the dead, and buried those who died. However, Rush’s hypothesis was incorrect about the immunity of Black Philadelphians: some would become sick with yellow fever.

During the epidemic, around 17,000 people would flee Philadelphia. However, the Black community remained and continued to take care of the sick in Philadelphia, even though they were getting sick themselves. Despite these sacrifices, Black Philadelphians were accused of taking advantage of the sick and dying once the epidemic ended. The main accuser was Mathew Carey, via his publication, A Short Account of the Malignant Fever.

Refuting these claims, Absalom Jones and Richard Allen wrote about the grim experience of Black Philadelphians, how they came to the city’s call as essential workers and took care of the sick, dying, and the dead in their own publication, A Narrative of the Proceedings of the Black People, During the Late Awful Calamity in Philadelphia in the Year 1793 and a Refutation of Some Censures, Thrown upon them in some late Publications. While these essential workers did not get the credit they deserved for their actions during the epidemic, they show up in letters that detailed peoples’ experiences and their contributions are clearly documented in letters that can be accessed today in historical archives and libraries.

Philadelphians would finally get relief when the seasons changed and the frost killed off the mosquitoes. There would continue periodic yellow fever outbreaks over the next 200 years,  but eventually, mosquitoes were discovered as the culprit- and today we have an effective vaccine. 

Want to try the lesson? Check out the lesson on the APS website here:

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