Today we know that the yellow fever virus is spread by mosquitoes and there is a vaccines that prevents it. Early Americans, however, were confused about what caused it, suspecting “miasma” (bad air) was to blame. They also had problems treating it. Yellow fever epidemics often disrupted Jewish communities, forcing them to flee cities and quarantine in the countryside. Surinamese doctor David Cohen Nassy helped treated victims of the yellow fever epidemic when he was in Philadelphia. He was very successful and wrote a book about what made his treatments successful.
