By the beginning of the eighteenth century, smallpox had killed countless people and was a constant threat in the world's major cities. British historian Thomas Babington Macaulay wrote in his History of England, "The smallpox was always present, filling the churchyard with corpses, tormenting with constant fears all whom it had not yet stricken, leaving on those whose lives it spared the hideous traces of its power, turning the babe into a changeling at which the mother shuddered, and making the eyes and cheeks of a betrothed maiden objects of horror to the lover."Communities used quarantine to control the spread of smallpox.

This required isolating infected individuals to keep them from transmitting the disease. Smallpox patients were housed in secluded facilities such as "smallpox ships" moored in harbors or "pesthouses" far from population centers. Smallpox victims stayed in these...