Smallpox one-third of the cases resulted in blindness. These deaths included those of four reigning monarchs and a queen consort. In the 20th century smallpox killed 200-300 million people. Edward Jenner discovered in 1798 that vaccination could prevent smallpox. In 1967, the WHO intensified efforts to eliminate the disease. Smallpox is one of two infectious diseases to have been eradicated, the other being rinderpest in 2011. The term "smallpox" was first used in Britain in the 15th century to distinguish the disease from syphilis, which was then known as the "great pox". Other historical names for the disease include pox, speckled
Mozart and smallpox increased crowding, making it easier for the disease to spread; yet effective protection from smallpox through a smallpox vaccine was discovered only at the end of the century (see below). The disease was a terrible one for its victims. Ian and Jenifer Glynn write: So what was it like? As children, we were told it was like chickenpox but worse. In fact it is not related to chickenpox, and it was unimaginably worse. In an unvaccinated population, something like 10–30 percent of all patients with smallpox would be expected to die. And dying was not easy; smallpox was, as Macaulay