In a July 5, 1776 letter to Joseph Ward, John Adams wrote, “The Small Pox has been our most fatal Enemy. Our People must reconcile themselves, to inocculating Hospitals.”
Before Edward Jenner developed vaccination in 1796, the more risky procedure of inoculation offered smallpox immunity to survivors. Historian Elizabeth A. Fenn suggested the disastrous effects of smallpox on Continental efforts in Canada helped Americans overcome misgivings about inoculation.
By January 1778, Gen. George Washington undertook the mass inoculation of soldiers and officers in the Continental Army. In her landmark book Pox Americana: The Great Smallpox Epidemic of 1775-82, Fenn wrote that Washington’s “little-recognized resolution to inoculate the Continental forces must surely rank among his most important decisions of the war.”
Elizabeth A. Fenn, Pox Americana: The Great Smallpox Epidemic of 1775-82 (New York: Hill and Wang, 2001), pages 27-28, 39, 134.