Inoculation was already a standard practice in Asian and African medicine, but involved serious risks, including the possibility that those inoculated would become contagious and spread the disease to others. In 1721,
Lady Mary Wortley Montagu had imported
variolation to Britain after having observed it in
Constantinople. While
Johnnie Notions had great success with his self-devised inoculation (and was reputed not to have lost a single patient), his method's practice was limited to the
Shetland Islands.
Voltaire wrote that at this time 60% of the population caught smallpox and 20% of the population died from it. He also stated that the
Circassians used the inoculation from time immemorial, and that the Turks may have borrowed the custom from them. In 1766 Daniel Bernoulli analysed smallpox morbidity and
mortality data to demonstrate the efficacy of inoculation. By 1768, the English physician
John Fewster had realised that prior infection with cowpox rendered a person immune to smallpox. In the years following 1770, at least five investigators in England and Germany (Sevel, Jensen, Jesty 1774, Rendell, Plett 1791) successfully tested a cowpox vaccine against smallpox in humans. successfully vaccinated with cowpox and presumably
induced immunity in his wife and two children during the 1774 smallpox epidemic, though it was not until Jenner's work that the procedure became widely understood. Jenner may have been aware of Jesty's procedures and success. In 1780
Jacques Antoine Rabaut-Pommier made similar observations in France. Jenner postulated that the
pus in blisters from sufferers of
cowpox (a disease similar to smallpox but much less virulent) protected them from smallpox. On 14 May 1796, he tested his hypothesis by inoculating
James Phipps, the eight-year-old son of Jenner's gardener. He scraped pus from cowpox blisters on the hands of Sarah Nelmes, a milkmaid who had caught cowpox from a cow called Blossom). Phipps was the 17th case described in Jenner's first paper on
vaccination. Jenner inoculated Phipps through two small cuts on his arm that day; this led to a fever and some uneasiness, but no full-blown infection. The American physician
Donald Hopkins has written, "Jenner's unique contribution was not that he inoculated a few persons with cowpox, but that he then proved [by subsequent challenges] that they were immune to smallpox. Moreover, he demonstrated that the protective cowpox pus could be effectively inoculated from person to person, not just directly from cattle." Some of his conclusions were correct, some erroneous; modern microbiological and microscopic methods would make his studies easier to reproduce. The medical establishment deliberated at length over his findings before accepting them. Eventually, vaccination was accepted, and in 1840, the British government banned variolationthe use of smallpox to induce immunityand provided vaccination using cowpox free of charge (see
Vaccination Act). The success of Jenner's discovery soon spread around Europe and was used
en masse in the Spanish
Balmis Expedition (1803–1806), a three-year-long mission to the Americas, the Philippines,
Macao and China led by
Francisco Javier de Balmis with the aim of giving the smallpox vaccine to thousands. The expedition was successful, and Jenner wrote: "I don't imagine the annals of history furnish an example of philanthropy so noble, so extensive as this".
Napoleon, who at the time was
at war with Britain, had all his French troops vaccinated, awarded Jenner a medal, and at Jenner's request, released two English prisoners of war, allowing them to return home. Napoleon remarked he could not "refuse anything to one of the greatest benefactors of mankind". Jenner's continuing work on vaccination prevented him from continuing his ordinary medical practice. He was supported by his colleagues and
King George III in petitioning
Parliament, and was granted £10,000 for his work on vaccination in 1802. In 1807 he was granted another £20,000 after the Royal College of Physicians confirmed the widespread efficacy of vaccination. File:"Edward Jenner advising a farmer to vaccinate his family". O Wellcome V0018221.jpg|
Edward Jenner advising a farmer to vaccinate his family. Oil painting by an English painter, File:A cow's udder with vaccinia pustules and human arms exhibiti Wellcome V0016678.jpg|Jenner's discovery of the link between cowpox pus and smallpox in humans helped him to create the smallpox vaccine. File:Jenner phipps 01 (cropped).jpg|Jenner performing his first vaccination on
James Phipps, a boy of age 8, on 14 May 1796 File:The cow pock.jpg|
James Gillray's 1802 caricature of Jenner vaccinating patients who feared it would make them sprout cowlike appendages. File:Jenner and his two colleagues seeing off three anti-vaccinat Wellcome V0011075.jpg|1808 cartoon showing Jenner,
Thomas Dimsdale and
George Rose seeing off anti-vaccination opponents File:Edward_Jenner._Photograph_of_a_sculpture_by_Giulio_Monteverd_Wellcome_V0028722.jpg|1873 sculpture of
Jenner Vaccinating His Own Son Against Smallpox by the Italian sculptor
Giulio Monteverde,
Galleria Nazionale d'Arte Moderna, Rome == Later life ==