None. The area was chosen, at the recommendation of President Washington, by the New York City-based congress in the Residence Act of 1790, which also made Philadelphia the temporary capital. The Constitution had already stipulated the creation of a Federal District to act as a national capital, and the site was chosen between Maryland and Virginia as a concession to the south. The city was designed in 1791 and construction of the Capitol Building began in 1793. The Capitol was officially moved to Washington, D.C. in 1801 following the completion of the Capitol Building and White House.

Philadelphia served as the temporary capitol from the end of 1790 to early 1800. The Yellow fever in Philadelphia was at its peak in the fall of 1793, mostly between the end of the Second Congress and convening of the Third. The regular schedule of Congress was not affected by the fever.

President Washington remained at the President's House in Philadelphia until September of 1793, when he left to place the cornerstone of the new Capitol Building. He remained at his home at Mount Vernon until November, and returned to the President's House in time for the convening of the Third Congress in December.

The claim of an "exodus from Philadelphia" is false as well. While almost half of the population fled the city, most returned after the "all clear" was declared on November 14th. From the 1790 census to the 1800 census, Philadelphia grew by 45%, and continued its streak of population growth for the next 150 years. This is the exact opposite of an exodus from Philadelphia.