Yellow fever the introduction of sugar plantations created the conditions for mosquito and viral reproduction, and subsequent outbreaks of yellow fever. Deforestation reduced populations of insectivorous birds and other creatures that fed on mosquitoes and their eggs. Although yellow fever is most prevalent in tropical-like climates, the northern United States were not exempted from the fever. The first outbreak in English-speaking North America occurred in New York City in 1668, and a serious one afflicted Philadelphia in 1793. English colonists in Philadelphia and the French in the Mississippi River Valley recorded major outbreaks in 1669, as well as those occurring later in
1793 Philadelphia yellow fever epidemic the personal letters, which are largely held by Quaker colleges in the area. While Powell did not write a scholarly history of the epidemic, his work reviewed its historical importance. Since the mid-twentieth century, scholars have studied aspects of the epidemic, first in papers. For example, Martin Pernick's "Politics, Parties, and Pestilence: Epidemic Yellow Fever in Philadelphia and the Rise of the First Party System," developed statistical evidence to show that Republican doctors generally used Rush's therapies and Federalist doctors used Kuhn's. Scholars celebrated the 200th anniversary of the epidemic with the publication of papers on various aspects of the