Edward Jenner developed a vaccination for smallpox in 1796 after observing the seeming immunity provided to milkmaids by a previous infection of cowpox. As is seen in this poster from Liverpool, those without the vaccine still suffered the lethal consequences of the disease. In 1853, two years after this poster was used, vaccination of children was made compulsory by the Vaccination Act. The Smallpox virus is now considered to have been eradicated with the last endemic cases recorded in Somalia in 1977.
Owner: The National Archives UK
Source: Flickr Commons