Edward B. Jenner (May 17, 1749 - January 26, 1823) was an English physician and scientist who is most recognized for introducing and popularizing an effective and relatively safe means of vaccination against smallpox, a discovery that proved to be one of the most significant medical advances of all time.

Although inoculations using dried smallpox secretions had been known for centuries in China and had spread to the Ottoman Empire and then England before Jenner's time, his vaccine utilizing material from a cowpox lesion was safer, more effective, and without the risk of smallpox transmission. Vaccination to prevent smallpox was soon practiced all over the world. Eventually, a disease that had killed many hundreds of millions, and disfigured and blinded countless more, was completely eradicated. It is the only infectious disease in humans that has been completely eradicated.

Jenner also coined the term immunization, which in its original meaning specifically referred to the protection conferred against smallpox using material from cowpox virus. Jenner called the material used for inoculation "vaccine," from the root word vacca, which is Latin for cow.

Jenner also was a naturalist, who studied his natural surroundings in Berkeley, Gloucestershire, in rural England; was a horticulturist; and discovered the fossils of a plesiosaur. He became a Fellow of the Royal Society based on his study of the nesting habits of the cuckoo.

Although Jenner was not the first to discover the practice of inoculation, and even the use of cowpox as vaccine predated him, his leadership and intellectual qualities lead to systematically developing, testing, and popularizing this method that saved countless lives. Ironically, the first experiment he performed, on a young boy, would be considered unethical by current standards, but lead to major benefit for humanity.

Early life

Jenner trained in Chipping Sodbury, Gloucestershire as an apprentice to John Ludlow, a surgeon, for eight years from the age of 13. In 1770, Jenner went up to London to study surgery and anatomy under the surgeon John Hunter and others at St George's, University of London. Hunter was the preeminent medical teacher in Britain (Last 2002), a noted experimentalist, and later a fellow of the Royal Society.

William Osler records that Jenner was a student to whom Hunter repeated William Harvey's advice, very famous in medical circles (and characteristically Enlightenment), "Don't think, try." Jenner, therefore, was noticed early by men famous for advancing the practice and institutions of medicine. Hunter remained in correspondence with him over natural history and proposed him for the Royal Society. Returning to his native countryside by 1773, he became a successful general practitioner and surgeon, practicing in purpose-built premises at Berkeley.

Jenner and others formed a medical society in Rodborough, Gloucestershire, meeting to read papers on medical subjects and dine together. Jenner contributed papers on angina pectoris, ophthalmia, and valvular disease of the heart and commented on cowpox. He also belonged to a similar society which met in Alveston, near Bristol (RCP).

He was elected Fellow of the Royal Society in 1788, following a careful study combining observation, experiment, and dissection into a description of the previously misunderstood life of the cuckoo in the nest.

Common Cuckoo

Jenner's description of the newly-hatched cuckoo pushing it's host's eggs and fledglings from the nest was confirmed in the twentieth century (JM) when photography became feasible. Having observed the behavior, he demonstrated an anatomical adaptation for it-the baby cuckoo has a depression in its back that is not present after 12 days of life, in which it cups eggs and other chicks to push them out of the nest. It had been assumed that the adult bird did this but the adult does not remain in the area for sufficiently long. His findings were published in the Philosophical Transactions of the Royal Society in 1787.

He married Catherine Kingscote (died 1815 from tuberculosis) in March 1788 having met her when balloons were hot science, and he and other Fellows were experimenting with them. His trial balloon descended into Kingscote Park, owned by Anthony Kingscote, Catherine being one of his three daughters.

Jenner did not take any examinations to receive his medical degree, but purchased a medical degree in 1792, from a Scottish University, the University of St. Andrews, and subsequently would apply for a degree from Oxford University, which he was granted (Last 2002).


Smallpox at one time was a very deadly disease, that is estimated to have killed 400,000 Europeans each year during the 18th century (including five reigning monarchs), and was responsible for a third of all blindness (Behbehani 1983). Between 20 to 60 percent of all those infected-and over 80 percent of infected children-died from the disease (Riedel 2005). During the twentieth century, it is estimated that smallpox was responsible for 300 to 500 million deaths (Koplow 2003).

A method of inoculating against smallpox was known from Asia centuries before Jenner. Basically, when the human immune system is exposed to a disease once, it can develop the ability to quickly respond to a subsequent infection. Therefore, by exposing an individual to an immunogen in a controlled way, the person's body will then be able to protect itself from infection later on in life. One does not necessarily have to be exposed to the natural infection, but exposure to a similar agent can confer an increased resistance to the disease.

Recognizing that an infectious disease, once overcome, did not normally reappear, people have tried to prevent getting a disease by purposely inoculating themselves with infected material. This is considered to have first been done successfully with smallpox before 200 B.C.E. (NMAH 2007), and having been practiced in India as early as 1000 B.C.E. (Bourzac 2002). However, this idea of such an early treatment has been challenged and the earliest confirmed inoculations are from China around 1000 C.E. (Last 2002), and were widely practiced during the Ming Dynasty (Temple 1986).

These early inoculations involved the process of variolation, involving either nasal insufflation of powdered smallpox scabs, or scratching material from a smallpox lesion into the skin. However, because the person was actually infected with the virus, a severe infection could result, and the person could transmit smallpox to others. However, the mortality rate was much less than the contracting the disease itself.

From China, this practice of variolation spread along the silk route, reaching Asia Minor sometime in the seventeenth century. In 1718, Lady Mary Wortley Montague, wife of the British ambassador to the Ottoman Empire, reported that the Turks have a habit of deliberately inoculating themselves with fluid taken from mild cases of smallpox and she inoculated her own children (Behbehani 1983). She imported this idea to England when she returned home, and many educated English families used this method to offer some protection against smallpox (Last 2002). Jenner himself was inoculated at a young age (Gross and Sepkowitz 1998).

Around the time of Jenner, smallpox was greatly feared, as one in three of those who contracted the disease died, and those who survived were often badly disfigured. Voltaire recorded that 60.243 percent of people caught smallpox, with 20 percent of the population dying of it.

It was noticed by many that people who had been infected with cowpox, a milder relative of the smallpox virus, did not get smallpox. After 1770, there were at least several people in England and Germany (Sevel, Jensen, Jesty 1774, Rendall, Plett 1791) who had successfully tested the possibility of using the cowpox vaccine as an immunization for smallpox in humans (Plett 2006).

Jenner's Initial TheoryIn fact, Jenner thought the initial source of infection was a disease of horses, called "the grease," and that this was transferred to cows by farm workers, transformed, and then manifested as cowpox. From that point on he was correct, the complication probably arose from coincidence.

In 1774, during a smallpox epidemic, Dorset farmer, Benjamin Jesty had successfully induced immunity in his wife and two children with cowpox. There was a popular belief that people infected and recovered from cowpox did not get smallpox, and Jesty noticed that "milkmaids" did not become infected with smallpox, or displayed a milder form. Jestey took the pus from an infected cow's udder and inoculated his wife and children with cowpox.

It is not known whether Jenner had the advantage of hearing stories of Jesty and perhaps others deliberately arranging cowpox infection of their families and of a reduced risk in those families. However, noting the common observation that milkmaids did not generally get smallpox, Jenner theorized that the pus in the blisters that milkmaids received from cowpox protected the milkmaids from smallpox.

Known: that smallpox was more dangerous than variolation and cowpox less dangerous than variolation.

The hypothesis tested: That infection with cowpox would give immunity to smallpox.

The test: If variolation failed to produce an infection, Phipps was shown to be immune to smallpox.

The consequence: Immunity to smallpox could be induced much more safely.

On 14 May 1796, Jenner tested his theory by inoculating James Phipps, a young boy of 8 years old, with material from the cowpox blisters of the hand of Sarah Nelmes, a milkmaid who had caught cowpox from a cow called Blossom (JM). Blossom's hide now hangs on the wall of the library at St George's medical school (now in Tooting), in commemoration of one of the school's most renowned alumni. Phipps was the 17th case described in Jenner's first paper on vaccination.

Jenner inoculated Phipps with cowpox pus in both arms on one day, by scraping the pus from Nelmes' blisters onto a piece of wood then transferring this to Phipps' arms. This produced a fever and some uneasiness but no great illness. Later, he injected Phipps with variolous material, which would have been the routine attempt to produce immunity at that time. No disease followed. Jenner reported that later the boy was again challenged with variolacious material and again showed no sign of infection.

He continued his research and reported it to the Royal Society, who did not publish the initial report. After improvement and further work, he published a report of twenty-three cases, mostof theim children that he had inoculated, all of whom survived unharmed and did not get smallpox. Some of Jenner's conclusions were correct, and some erroneous. The medical establishment, as cautious then as now, considered his findings for some time before accepting them. Eventually vaccination was accepted, and in 1840, the British government banned variolation and provided vaccination free of charge.

1802 caricature of Jenner vaccinating patients who feared it would make them sprout cowlike appendages.

Later life

Jenner's continuing work on vaccination prevented his continuing his ordinary medical practice. He was supported by his colleagues and the King in petitioning Parliament and was granted £10,000 for his work on vaccination. In 1806, he was granted another £20,000 for his continuing work.

In 1803, in London, he became involved with the Jennerian Institution, a society concerned with promoting vaccination to eradicate smallpox. In 1808, with government aid, this society became the National Vaccine Establishment. Jenner became a member of the Medical and Chirurgical Society on its foundation in 1805, and subsequently presented to them a number of papers. This is now the Royal Society of Medicine.

Returning to London in 1811, Jenner observed a significant number of cases of smallpox after vaccination occurring. He found that in these cases the severity of the illness was notably diminished by the previous vaccination. In 1821, he was appointed Physician Extraordinary to King George IV, a considerable national honor, and was made Mayor of Berkeley and Justice of the Peace. He continued his interests in natural history. In 1823, the last year of his life, he presented his Observations on the Migration of Birds to the Royal Society.

He was found in a state of apoplexy on 25 January 1823, with his right side paralyzed. He never rallied, and died of what was apparently a stroke (he had suffered a previous stroke) on January 26, 1823 at the age of 73. He was survived by one son and one daughter, his elder son having died of tuberculosis at the age of 21.


In 1980, the World Health Organization declared smallpox an eradicated disease. This was the result of coordinated public health efforts by many people, but vaccination was an essential component. Although it was declared eradicated, some samples still remain in laboratories in Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia in the United States, and State Research Center of Virology and Biotechnology VECTOR in Koltsovo, Novosibirsk Oblast, Russia.


Bronze in Kensington Gardens
  • Jenner's house is now a small museum housing among other things the horns of the cow, Blossom. It lies in the Gloucestershire village of Berkeley.
  • Jenner was buried in the chancel of the parish church of Berkeley
  • A statue, by Robert William Sievier, was erected in the nave of Gloucester Cathedral
  • A statue was erected in Trafalgar Square, later moved to Kensington Gardens (RCP)
  • A small grouping of villages in Somerset County, Pennsylvania, United States, were named in honour of Jenner by early nineteenth century English settlers, including what are now the towns of Jenners, Jenner Township, Jenner Crossroads and Jennerstown, Pennsylvania.


  • 1798 An Inquiry Into the Causes and Effects of the Variolæ Vaccinæ
  • 1799 Further Observations on the Variolœ Vaccinœ
  • 1800 A Continuation of Facts and Observations relative to the Variolœ Vaccinœ 40pgs
  • 1801 The Origin of the Vaccine Inoculation 12pgs


  • Aly, A., and S. Aly. 1996. Smallpox. N. Engl. J. Med. 335(12): 900-901. PMID 8778626. Retrieved November 17, 2008.
  • Andreae, H. 1973. Edward Jenner, initiator of cowpox vaccination against human smallpox, died 150 years ago (Article in German). Das Offentliche Gesundheitswesen 35(6): 366-7. PMID 4269783. Retrieved November 17, 2008.
  • Baron, J. 1827. The Life of Edward Jenner MD LLD FRS. London: Henry Colburn.
  • Baxby, D. 1996. The Jenner bicentenary: The introduction and early distribution of smallpox vaccine. FEMS Immunol. Med. Microbiol. 16(1): 1-10. PMID 8954347. Retrieved November 17, 2008.
  • Baxby, D. 1996. The Jenner bicentenary; still uses for smallpox vaccine. Epidemiol. Infect 116(3): 231-234. PMID 8666065. Retrieved November 17, 2008.
  • Baxby, D. Jenner and the control of smallpox. Transactions of the Medical Society of London 113: 18-22. PMID 10326082. Retrieved November 17, 2008.
  • Behbehani, A. M. 1983. The smallpox story: Life and death of an old disease. Microbiol Rev 47(4): 455-509. PMID 6319980. Retrieved November 17, 2008.
  • Blakemore, C., and S. Jennett. 2001. The Oxford Companion to the Body. New York: Oxford University Press. ISBN 019852403X.
  • Bloch, H. 1993. Edward Jenner (1749-1823). The history and effects of smallpox, inoculation, and vaccination. Am. J. Dis. Child. 147(7): 772-774. PMID 8322750. Retrieved November 17, 2008.
  • Bourzac, K. 2002. Smallpox: Historical review of a potential bioterrorist tool. Journal of Young Investigators 6(3). Retrieved November 17, 2008.
  • Budai, J. 1996. 200th anniversary of the Jenner smallpox vaccine (Article in Hungarian) Orvosi hetilap 137(34): 1875-7. PMID 8927342. Retrieved November 17, 2008.
  • Cartwright, K. 2005. From Jenner to modern smallpox vaccines. Occupational Medicine 55(7): 563. PMID 16251374. Retrieved November 17, 2008.
  • Cook, G. C. 1996. Dr William Woodville (1752-1805) and the St Pancras Smallpox Hospital. Journal of Medical Biography 4(2): 71-78. PMID 11616267. Retrieved November 17, 2008.
  • Dunn, P. M. 1996. Dr. Edward Jenner (1749-1823) of Berkeley, and vaccination against smallpox. Arch. Dis. Child. Fetal Neonatal Ed. 74(1): F77-8. PMID 8653442. Retrieved November 17, 2008.
  • Friedrich, I. 1973. A cure for smallpox. On the 150th anniversary of Edward Jenner's death (Article in Hungarian). Orvosi Hetilap 114(6): 336-338. PMID 4567814. Retrieved November 17, 2008.
  • Gross, C. P., and K. A. Sepkowitz. 1998. The myth of the medical breakthrough: Smallpox, vaccination, and Jenner reconsidered. Int. J. Infect. Dis. 3(1): 54-60. PMID 9831677. Retrieved November 17, 2008.
  • Hammarsten, J. F., W. Tattersall, and J. E. Hammarsten. 1979. Who discovered smallpox vaccination? Edward Jenner or Benjamin Jesty? Trans. Am. Clin. Climatol. Assoc. 90: 44-55. PMID 390826. Retrieved November 17, 2008.
  • Hinman, A. R. 2002. Immunization. In L Breslow, Encyclopedia of Public Health. New York: Macmillan Reference USA/Gale Group Thomson Learning. ISBN 0028658884.
  • Jenner Museum. n.d. Edward Jenner and the cuckoo. The Jenner Museum. Retrieved November 17, 2008.
  • Kempa, M. E. 1996. Edward Jenner (1749-1823): Benefactor to mankind (100th anniversary of the first vaccination against smallpox) (Article in Polish). Pol. Merkur. Lekarski 1(6): 433-4. PMID 9273243. Retrieved November 17, 2008.
  • Koplow, D. A. 2003. Smallpox: The Fight to Eradicate a Global Scourge. Berkeley: University of California Press. ISBN 0520242203.
  • Kumate-Rodríguez, J. 1996. Bicentennial of smallpox vaccine: Experiences and lessons (Article in Spanish). Salud Pública de México 38(5): 379-85. PMID 9092091. Retrieved November 17, 2008.
  • Larner, A. J. 1996. Smallpox. N. Engl. J. Med. 335(12): 901. PMID 8778627. Retrieved November 17, 2008.
  • Last, J. M. 2002. Edward Jenner. In L Breslow, Encyclopedia of Public Health. New York: Macmillan Reference USA/Gale Group Thomson Learning. ISBN 0028658884.
  • MacNalty, A. S. 1968. The prevention of smallpox: from Edward Jenner to Monckton Copeman. Medical History 12(1): 1-18. PMID 4867646. Retrieved November 17, 2008.
  • Magner, J. 1996. Smallpox. N. Engl. J. Med 335(12): 900. PMID 8778624. Retrieved November 17, 2008.
  • Meynell, E. 1995. French reactions to Jenner's discovery of smallpox vaccination: The primary sources. Social History of Medicine 8(2): 285-303. PMID 11639810. Retrieved November 17, 2008.
  • National Museum of American History (NMAH). 2007. History of vaccines. Smithsonian National Museum of American History. Retrieved November 17, 2008.
  • Plett, P. C. 2006. Peter Plett and other discoverers of cowpox vaccination before Edward Jenner (in German). Sudhoffs Arch 90(2): 219-32.
  • Poliakov, V. E. 1985. Edward Jenner and vaccination against smallpox (Article in Russian). Meditsinskaia Sestra 44(12): 49-51. PMID 3912642. Retrieved November 17, 2008.
  • Rathbone, J. 1996. Lady Mary Wortley Montague's contribution to the eradication of smallpox. Lancet 347(9014): 1566. PMID 8684145. Retrieved November 17, 2008.
  • Riedel, S. 2005. Edward Jenner and the history of smallpox and vaccination. Proc (Bayl Univ Med Cent) 18(1): 21-5. PMID 16200144. Retrieved November 17, 2008.
  • Rodrigues, B. A. 1975. Smallpox eradication in the Americas. Bulletin of the Pan American Health Organization 9(1): 53-68. PMID 167890. Retrieved November 17, 2008.
  • Roses, D. F. 1992. From Hunter and the Great Pox to Jenner and smallpox. Surgery, Gynecology & Obstetrics 175(4): 365-372. PMID 1411896. Retrieved November 17, 2008.
  • Royal College of Physicians (RCP). n.d. Jenner, Edward (1749-1823). Royal College of Physicians. Retrieved November 17, 2008.
  • Tan, S. Y. 2004. Edward Jenner (1749-1823): Conqueror of smallpox. Singapore Medical Journal 45(11): 507-8. PMID 15510320. Retrieved November 17, 2008.
  • Temple, R. 1986. The Genius of China: 3,000 Years of Science, Discovery, and Invention. New York: Simon and Schuster. ISBN 0671620282.
  • Theves, G. 1997. Smallpox: An historical review (Article in German). Bulletin de la Société des sciences médicales du Grand-Duché de Luxembourg 134(1): 31-51. PMID 9303824. Retrieved November 17, 2008.
  • Turk, J. L., and E. Allen. 1990. The influence of John Hunter's inoculation practice on Edward Jenner's discovery of vaccination against smallpox. Journal of the Royal Society of Medicine 83(4): 266-7. PMID 2187990. Retrieved November 17, 2008.
  • Udovitskaia, E. F. 1966. Edward Jenner and the history of his scientific achievement. (On the 170th anniversary of the discovery of smallpox vaccination) (Article in Russian). Vrachebnoe delo 11: 111-115. PMID 4885910. Retrieved November 17, 2008.
  • van Oss, C. J. 2000. Inoculation against smallpox as the precursor to vaccination. Immunol. Invest. 29(4): 443-446. PMID 11130785. Retrieved November 17, 2008.
  • Voigt, K. 1964. The pharmacy display window. Edward Jenner discovered smallpox vaccination (Article in German). Pharmazeutische Praxis 106: 88-89. PMID 14237138. Retrieved November 17, 2008.
  • Willis, N. J. 1997. Edward Jenner and the eradication of smallpox. Scottish Medical Journal 42(4): 118-121. PMID 9507590. Retrieved November 17, 2008.
  • Wynder, E. L. 1974. A corner of history: Jenner and his smallpox vaccine. Preventive Medicine 3(1): 173-175. PMID 4592685. Retrieved November 17, 2008.