Bioterrorism was among the many concerns that occupied Gen. George Washington in the winter of 1775, six months after taking command of the ragtag American forces in Cambridge, Massachusetts. The years of the American Revolution coincided nearly perfectly with a smallpox epidemic that spanned the North American continent claiming more than 130,000 lives from 1775 to 1782. And Washington had reason to believe that the British were waging germ warfare by deliberately infecting American troops with the highly contagious and deadly smallpox virus.

Washington knew firsthand the misery of the disease having survived a smallpox infection years earlier; he was well aware that a smallpox epidemic would ravage his fledgling armies. It is impossible to know with certainty whether the British practiced germ warfare against the Americans or not. However, a series of letters from Washington to Congress written in December 1775 reveal that the threat of biological warfare was sufficiently real in his mind to merit mention in his official reports. First, his fears were based on a report that he heard and then fuelled by what he saw with his own eyes.