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
History of HIV/AIDS the necessity to supply workers and because firearms became more widely available. The colonial authorities also gave many vaccinations against smallpox, and injections, of which many would be made without sterilising the equipment between uses (unsafe or unsterile injections). Chitnis "et al." proposed that both these parenteral risks and the prostitution associated with forced labor camps could have caused serial transmission (or serial passage) of SIV between humans (see discussion of this in the next section). In addition, they proposed that the conditions of extreme stress associated with forced labor could depress the immune system of workers, therefore prolonging the