Abstract: Public health organizations, including the Centers for Disease Control and Prevention, the World Health Organization, and the U.S. Department of Health and Human Services, are greatly concerned that a new influenza type A outbreak will result in a rapid spread of infectious disease, overwhelming existing medical response infrastructures. Each of these organizations has published planning guides that call upon local and community organizers to begin planning for such an event. To establish insight and provide context for these organizers, this paper presents a case analysis of the Philadelphia yellow fever outbreak of 1793.