Vaccination disease people tried to prevent by inoculation and was the first disease for which a vaccine was produced. The smallpox vaccine was invented in 1796 by English physician Edward Jenner and although at least six people had used the same principles years earlier he was the first to publish evidence that it was effective and to provide advice on its production. Louis Pasteur furthered the concept through his work in microbiology. The immunization was called "vaccination" because it was derived from a virus affecting cows ( 'cow'). Smallpox was a contagious and deadly disease, causing the deaths of 20–60% of
1947 New York City smallpox outbreak died May 7, a week after receiving her vaccination. According to the Center for Disease Control, the rate for post-vaccination encephalitis following the smallpox vaccine is 3 to 12 per million, and the fatality rate is about 1 in a million. (Since this was the largest vaccination campaign ever, it is likely to have contributed substantially to the C.D.C.'s data and estimates.) Even President Harry S. Truman received a vaccination for a brief trip to give a speech in New York City to news reporters. There were two additional cases of smallpox transmitted in the New York City area at