Edward Jenner (17 May 1749 – 26 January 1823) was an English physician and scientist who pioneered the concept of vaccines and created the smallpox vaccine, the world's first vaccine. The terms vaccine and vaccination are derived from Variolae vaccinae ("pustules of the cow"), the term devised by Jenner to denote cowpox. He used it in 1798 in the title of his Inquiry into the Variolae vaccinae known as the Cow Pox, in which Jenner described the protective effect of cowpox against smallpox.

Jenner is often called "the father of immunology", and his work is said to have saved "more lives than any other man". In Jenner's time, smallpox killed around 10% of the global population, with the number as high as 20% in towns and cities where infection spread more easily. In 1821, he was appointed physician to King George IV, and was also made mayor of Berkeley and justice of the peace. Jenner was a member of the Royal Society. In the field of zoology, he was among the first modern scholars to describe the brood parasitism of the cuckoo (Aristotle also noted this behaviour in his History of Animals). In 2002, Jenner was named in the BBC's list of the 100 Greatest Britons.

Early life Edward Jenner was born on 17 May 1749 in Berkeley, Gloucestershire, England, as the eighth of nine children. His father, the Reverend Stephen Jenner, was the vicar of Berkeley, so Jenner received a strong basic education.

Education and training When Jenner was young, he went to school in Wotton-under-Edge at Katherine Lady Berkeley's School and in Cirencester. During this time, Jenner was inoculated (by variolation) for smallpox, which had a lifelong effect upon his general health. At age 13, Jenner was apprenticed for seven years to Daniel Ludlow, a surgeon of Chipping Sodbury, South Gloucestershire, gaining most of the experience needed to become a surgeon himself.

In 1770, at age 21, Jenner became apprenticed in surgery and anatomy under the surgeon John Hunter and others at St George's Hospital, London. William Osler records that Hunter gave Jenner William Harvey's advice, well known in medical circles (and characteristic of the Age of Enlightenment), "Don't think; try." Hunter remained in correspondence with Jenner over natural history and proposed him for the Royal Society. Returning to his native countryside by 1773, Jenner became a successful family doctor and surgeon, practising on dedicated premises at Berkeley. In 1792, "with twenty years' experience of general practice and surgery, Jenner obtained the degree of MD from the University of St Andrews".

Later life Jenner and others formed the Fleece Medical Society or Gloucestershire Medical Society, so called because it met in the parlour of the Fleece Inn, Rodborough, Gloucestershire. Members dined together and read papers on medical subjects. Jenner contributed papers on angina pectoris, ophthalmia, and cardiac valvular disease and commented on cowpox. He also belonged to a similar society which met in Alveston, near Bristol."Papers at the Royal College of Physicians summarised" .

Jenner became a master mason on 30 December 1802, in Lodge of Faith and Friendship #449. From 1812 to 1813 he served as worshipful master of Royal Berkeley Lodge of Faith and Friendship."Edward Jenner biography". Grand Lodge of British Columbia and Yukon A.F. & A. M. Retrieved 22 August 2016

Zoology Jenner was elected a fellow of the Royal Society in 1788, following his publication of a careful study of the previously misunderstood life of the nested cuckoo, a study that combined observation, experiment and dissection.

Jenner described how the newly hatched cuckoo pushed its host's eggs and fledgling chicks out of the nest (contrary to existing belief that the adult cuckoo did it).Jenner Museum: Cuckoo Having observed this behaviour, Jenner demonstrated an anatomical adaptation for itthe baby cuckoo has a depression in its back, not present after 12 days of life, that enables it to cup eggs and other chicks. The adult does not remain long enough in the area to perform this task. Jenner's findings were published in Philosophical Transactions of the Royal Society in 1788."Observations on the Natural History of the Cuckoo". By Mr. Edward Jenner. In a Letter to John Hunter, Esq. F.R.S. Jenner, E Philosophical Transactions of the Royal Society of London (1776–1886). 1788. 78:219–237 (Archived Text)

"The singularity of its shape is well adapted to these purposes; for, different from other newly hatched birds, its back from the scapula downwards is very broad, with a considerable depression in the middle. This depression seems formed by nature for the design of giving a more secure lodgement to the egg of the Hedge-sparrow, or its young one, when the young Cuckoo is employed in removing either of them from the nest. When it is about twelve days old, this cavity is quite filled up, and then the back assumes the shape of nestling birds in general."(Letter to Hunter at the Royal Society, as above) Jenner's nephew assisted in the study.

Jenner's understanding of the cuckoo's behaviour was not entirely believed until the artist Jemima Blackburn, a keen observer of birdlife, saw a blind nestling pushing out a host's egg. Blackburn's description and illustration were enough to convince Charles Darwin to revise a later edition of On the Origin of Species.

Jenner's interest in zoology played a large role in his first experiment with inoculation. Not only did Jenner have a profound understanding of human anatomy due to his medical training, but he also understood animal biology and its role in human–animal trans-species boundaries in disease transmission. At the time, there was no way of knowing how important this connection would be to the history and discovery of vaccinations. This connection can be seen today; many present-day vaccinations include animal parts from cows, rabbits and chicken eggs, which can be attributed to the work of Jenner and his cowpox/smallpox vaccination.

Marriage and human medicine

Jenner married Catherine Kingscote in March 1788 (she died of tuberculosis in 1815). He might have met her while he and other fellows were experimenting with balloons. Jenner's trial balloon descended into Kingscote Park, Gloucestershire, owned by Catherine's father, Anthony Kingscote.Richard B. Fisher, Edward Jenner (Andre Deutsch, 1991) pp. 40–42 They had three children together: Edward Robert (1789–1810), Catherine Fitzhardinge (1794–1833),The Journal of Genealogy and Family History, Vol. 2, No. 1, page 23 Figure 2 (2018) and Robert Fitzhardinge (1797–1854), who was 11 months old when Edward Jenner inoculated him with his cowpox vaccine.John Baron, The life of Edward Jenner ... With illustrations of his doctrines, and selections from his correspondence (H. Colburn, 1838) Vol.1 pp. 147, republished (Cambridge University Press, 2014)

Jenner earned his MD from the University of St Andrews in 1792. He is credited with advancing the understanding of angina pectoris. In his correspondence with Heberden, Jenner wrote: "How much the heart must suffer from the coronary arteries not being able to perform their functions".Valentin Fuster, Eric J. Topol, Elizabeth G. Nabel (2005). "Atherothrombosis and Coronary Artery Disease". p. 8. Lippincott Williams & Wilkins

Invention of the vaccine

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. Robert Sutton's method had similar success in Suffolk. 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. from In 1766, Daniel Bernoulli analyzed smallpox morbidity and mortality data to demonstrate the efficacy of inoculation.reprinted in

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. For example, the Dorset farmer Benjamin Jesty 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. Jenner scraped pus from cowpox blisters on the hands of Sarah Nelmes, a milkmaid who had caught cowpox from a cow called Blossom (whose hide now hangs on the wall of the St George's Medical School library, now in Tooting, London). 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. On 1 July 1796, Jenner injected Phipps with variolous material, the routine method of immunisation at that time, and again no disease followed. Phipps was later challenged with variolous material and again showed no sign of infection. There were no unexpected side effects, and neither Phipps nor any other recipients underwent any future 'breakthrough' cases.

Jenner's biographer, John Baron, later speculated that it was Jenner's observation of the unblemished complexion of milkmaids that led to his understanding that it was possible to be inoculated against smallpox by being exposed to cowpox, that is, he did not build on the work of his predecessors. The milkmaid story is still widely repeated even though it appears to be a myth.

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." Jenner successfully tested his hypothesis on 23 additional subjects.

Jenner continued his research and reported it to the Royal Society, though the initial paper was not published. After revisions and further investigations, he published his findings on the 23 cases, including his 11-month-old son Robert. Some of Jenner's 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).