1793 Philadelphia yellow fever epidemic the origin of the fever nor that it was transmitted by mosquitoes (which was not verified until the late nineteenth century). The mayor and a committee of two dozen organized a fever hospital at Bush Hill and other crisis measures. The assistance of the Free African Society was requested by the city and readily agreed to by the members, based on the mistaken assumption that native Africans would have the same partial immunity to the new disease as many had to malaria, the most common source of fever epidemics during the summer months. Black nurses aided the sick and the
Yellow fever vaccine and Brazil in 2017 have further increased demand, while straining global vaccine supply. Therefore, to vaccinate susceptible populations in preventive mass immunization campaigns during outbreaks, fractional dosing of the vaccine is being considered as a dose-sparing strategy to maximize limited vaccine supplies. Fractional dose vaccination refers to administration of a reduced volume of vaccine dose, which has been reconstituted as per manufacturer recommendations. The first practical use of fractional doses of the yellow fever vaccine was in response to the 2016 outbreak in the Democratic Republic of Congo. Yellow fever vaccine Yellow fever vaccine is a vaccine that protects against