Yellow Fever
Attacks Philadelphia, 1793
With a population of approximately 55,000 in 1793, Philadelphia was America's largest city, its capital and its busiest port. The summer of that year was unusually dry and hot. The water levels of streams and wells were dangerously reduced, providing an excellent breeding ground for insects. By July the city's inhabitants were remarking on the extraordinary number of flies and mosquitoes that swarmed around the dock area. That same month, a trickle of refugees escaping Philadelphia's docks. Unbeknownst to the city's inhabitants, all the necessary ingredients for an unprecedented health disaster were now in place.
With them, the Caribbean refuges brought Yellow Fever. Philadelphia's ravenous mosquitoes provided the perfect vehicle for spreading the disease by first lunching on an infected victim and then biting a healthy one. The first fatalities appeared in July and the numbers grew steadily. The afflicted initially experienced pains in the head, back and limbs accompanied by a high fever. These symptoms would often disappear, leaving a false sense of security. Shortly, the disease would announce its return with an even more severe fever and turn the victim's skin a ghastly yellow while he vomited black clots of blood. Death soon followed as the victim slipped into a helpless stupor.
http://www.eyewitnesstohistory.com/yellowfever.htm
