Poxes great and small: The stories behind their names

The word "pox" indicated, during the late 15th century, a disease characterized by eruptive sores. When an outbreak of syphilis began in Europe during that time, it was called by many names, including the French term "la grosse verole" ("the great pox"), to distinguish it from smallpox, which was termed "la petite verole" ("the small pox"). Chickenpox was initially confused with smallpox until 1767, when the English physician William Heberden (1710-1801) provided a detailed description of chickenpox, differentiating it from smallpox. The cowpox virus was used by Edward Jenner (1749-1823) to develop a successful vaccine against smallpox. He devised the term "variolae vaccinae" ("smallpox of the cow") to denote cowpox. Jenner's pioneering work on a smallpox vaccine has led to the eradication of this disease and opened the way to preventing other infectious diseases, such as monkeypox, a poxvirus that is closely related to smallpox and that is currently infecting persons around the world. This contribution tells the stories behind the names of the various "poxes" that have infected humans: the great pox (syphilis), smallpox, chickenpox, cowpox, and monkeypox. These infectious diseases not only share a common "pox" nomenclature, but are also closely interconnected in medical history.