Jenner, Edward

(b. Berkely Gloucestershire, England, 17May 1749;d. Berkeley, 26 January 1823)

natural histroy, immunology, medicine.

Edward Jenner was the sixth and youngest child of the Reverend Stephen Jenner, rector of Rockhampton and vicar of Berkeley, a small market town in the Servern Valley. His mother was a daughter of the Reverend Henry Head, a former vicar of Berkeley. In addition to his church offices, Jenner’father owned a considerable amount of land in the vicinity of Berkeley.

In 1754, when Edward was five years old, both parents died within a few weeks of each other and he came under the guardianship of his elder brother, the Reverend Stephen Jenner, who had succeeded their father as rector of Rockhampton. Jenner’ first schooling was received from the Reverend Mr. Clissold at the nearby village of Wotton-under-Edge. Later he was sent to a grammar school at Cirencester. One of his favorite boyhood activities was searching for fossils among the oolite rocks of the countryside.

In 1761 Jenner was apprenticed to Daniel Ludlow, a surgeon of Sodbury, with whom he worked until 1770, when he went to London to study anatomy and surgery under John Hunter. Hunter had just taken over the large house of his brother William in Jermyn Street, and Jenner was one of Hunter’first boarding pupils. Jenner also served as Hunter’arranged the zoological specimens brought back by Joseph Banks from the first voyage of H. M. S. Endeavour. In 1773 Jenner returned to Berkeley, where he lived with his elder brother and began to practice medicine.

Jenner’s medical practice at Berkeley left him enough leisure time for activity in local medical societies, making observations in natural history, playing the flute, and now and then writing verse. His poetry has sometimes a simple beauty, his best poems being “Address to a Robin”and“The Signs of Rain“.

Hunter continually encouraged Jenner’s studies in natural history, for instance, by asking him to obtain particular specimens and to investigate temperatures of hibernating animals. Hunter incorporated many of Jenner’ observations in his own papers, published in the Philosophical Transactions of the Royal Society and in his book Observations on . . . the Animal Oeconomy (London, 1786).

On 6 March 1788 Jenner married Katherine Kingscote and moved to Chantry Cottage, a comfortable Georgian country house at Berkeley, where he resided, except for intervals at London and Cheltenham, for the rest of his life. His wife, who bore him four children, died on 13 September 1815.

In 1786 Jenner wrote a paper on the breeding habits of the cuckoo and Hunter submitted it to the Royal Society. Jenner had shown that when a cuckoo’s egg, laid in the nest of another bird such as the hedge sparrow, was hatched, the eggs or nestlings of the foster parent were thrown out of the nest, apparently by their own parents. Jenner had no explanation for this seemingly unnatural behavior. The paper was read before the society on 29 March 1787 and was accepted for publication in the Philosophical Transaction. Then, on 18 June 1787, Jenner discovered that it was the newly hatched cuckoo which ejected from the nest of its“foster parent” the hedge sparrow’ own unhatched eggs and nestlings. Accordingly, Jenner withdrew his original paper before publication and revised it. On 27 December 1787 he sent the revised report to Hunter, and it was read before the Royal Society on 13 March 1788.

When Jenner began medical practice at Berkeley, he was frequently asked to inoculate persons against smallpox. Smallpox inoculation had been introduced into England early in the eighteenth century. A person in good health was inoculated with matter from smallpox pustules and was thus given what was usually a mild case of the disease in order to confer immunity against further smallpox infection. The practice was dangerous, however, since smallpox thus induced could be severe or fatal, and it tended to spread smallpox among the population

Such inoculation was evidently not a common practice in the English countryside until about 1768, when it was improved by Robert Sutton of Debenham, Suffolk. Sutton required the patient to rest and maintain a strict diet for two weeks before inoculation. He inoculated by taking, on the point of a lancet, a very small quantity of fluid from an unripe smallpox pustule and introducing it between the outer and inner layers of the skin of the upper arm without drawing blood. He used no bandage to cover the incision.

Jenner began to inoculate against smallpox using Sutton’s method, but he soon found some patients to be completely resistant to the disease. On inquiry he found that these patients had previously had cowpox, the disease which produced a characteristic eruption on the teats of milk cows and was frequently transmitted to people who milked the cows. Jenner also found that among milkmen and milkmaids it was generally believed that contraction of cowpox prevented subsequent susceptibility to smallpox, although there had apparently been instances where this had not been the case. His fellow medical practitioners in the countryside did not agree that cowpox prevented smallpox with certainty.

As early as 1780 Jenner learned that the eruptions on the teats of infected cows differed. All were called cowpox and all could be communicated to the hands of the milkers, but only one kind created a resistance to smallpox. He called this type “true cowpox.” Jenner subsequently found that even true cowpox conferred immunity against smallpox only when matter was taken from the cowpox pustules before they were too old (as had been the case with Sutten’s smallpox fluid). Jenner though (mistakenly) that true cowpox was identical with a disease of the feet of horses known as “grease,” and that the pox was carried from horses to cattle on the hands of milkmen who also cared for horse. He also believed at that time that the cowpox could be transmitted from person to person, serving to protect them from smallpox. But he was not able to confirm his opinions for another sixteen years.

On 14 May 1796 Jenner inoculated James Phipps, an eight-year-old boy, with matter taken from a pustule on the arm of Sarah Nelmes, a milkmaid suffering from cowpox. The boy contracted cowpox and recovered within a few days. On 1 July 1796 Jenner inoculated him with smallpox, but the inoculation produced no effect. In June 1798 Jenner published at his own expense a slender volume of seventy-five pages, An Inquiry Into the Cause and Effects of the Variolae Vaccinae. In this work he described twenty-three cases in which cowpox had conferred a lasting immunity to smallpox. Jenner described “grease,”, the disease on the heels of horses, and suggested that it could cause cowpox in cows. He showed that cowpox was transmitted to the milkmaids, giving rise to pustules on their hands and arms but not to systemic disease. They recovered after a few days of mild illness and were thereafter immune to smallpox.

To describe the matter producing cowpox Jenner introduced the term “virus,” contending that the cowpox virus had to be acquired from the cow and that it gave permanent protection from smallpox. In Case IV of the Inquiry Jenner also describes a kind of reaction now known as aha- phylaxis. In 1791 one Mary Barge, who had had cowpox many years before, was inoculated with smallpox. A pale red inflammation appeared around the inoculation site and spread extensively, but it disappeared within a few days. Jenners noted how remarkable it was that the smallpox virus should produce such inflammation more rapidly than it could produce smallpox itself. He also observed that although cowpox gave immunity to smallpox, it did not confer similar immunity to the cowpox, itself.

Following the publication of Jenner’s book the practice of vaccination was adopted and spread with astonishing speed. It was taken up not only by medical practitioners but also by country gentlemen. clergymen, and schoolmasters. Jenner found that lymph taken from smallpox pustules might be dried in a glass tube or quill and kept for as long as three months without losing its effectiveness. The dried vaccine could thus be sent long distances. Jean de Carro, swiss physician living in Vienna, introduced vaccination on the continent of Europe and was instrumental in sending vaccine virus into Italy, Germany, Poland, and Turkey. In1801 Lord Elgin, British ambassador at Constantinople, sent vaccine virus received from de Carro overland to Bussora (Basra) on the Persian Gulf, and thence to Bombay. The marquis of Wellesley, governor general of India, actively pro- moted the distribution of the vaccine and many thousands of people were vaccinated in India during the next few years. In Massachusetts, Benjamin Waterhouse introduced vaccination to America with vaccine received from Jenner. Jenner also sent vaccine to President Jefferson, who vaccinated his family and his neighbors at Monticello.

After 1798 Jenner’s life was taken up almost entirely by the question of vaccination. He had to provide vaccine to those who requested it, explain the details of the procedure, and defend the practice against ill-informed criticism. He had to answer first the somewhat casual criticisms of Ingen-Housz and in 1799 the more serious attack of William Woodville, head of the London smallpox Hospital. Woodville had inadvertently inoculated his patients with small-pox when he attempted to vaccinate them, amis- fortune which produced serious cases of smallpox and at least one death. Jenner wrote a number of pamphlets in defense of vaccination. He was obliged to spend extended periods of time at London and to carry on a vast correspondence. In 1802 the British Parliament voted him a grant of £10,000 in recogni-tion of his discovery and in 1806 an additional grant of £20,000. In 1803 the Royal Jennerian Society was founded at London to promote vaccination and Jenner took a large part in its affairs; it was superseded in 1808 by a national vaccination program.

Although Great Britain and France were at war, in 1804 Napoleon had a medal struck in honor of Jenner’s discovery and in 1805 he made vaccination compulsory in the French army. At Jenner’s request he also released certain Englishmen who had been interned in France. In1813 the University of Oxford awarded Jenner an honorary M.D. degree.

After his wife’s death in 1815, Jenner rarely left Berkeley and never visited London. He resumed his studies in natural history and completed a paper on the migration of birds, published after his death, in which he showed that birds appeared to migrate into England in summer for the purpose of reproduction, and that the ovaries of the female and testes of the male were enlarged at that time. Jenner also served as a justice of the peace at Berkeley.

The day before his death he walked to a neighboring village, where he ordered that fuel be provided for certain poor families. In 1820 he had suffered a mild stroke, and on 25January 1823, a severe one. He died early the next morning.

Jenner’s discovery of vaccination made possible the immediate control of smallpox and the saving of untold lives. It also made possible, as Jenner realized, the ultimate eradication of smallpox as a disease, an end which is only now (1972) within sight for the whole world. Jenner must be considered the founder of immunology; in vaccination he made the first use of an attenuated virus for immunization. For his coining of the term “virus”his effort to describe the natural history of the cowpox virus, and his descript-tion of anaphylaxis, he must be considered the first pioneer of the modern science of virology.

BIBLIOGRAPHY

A complete description of Jenner’ published work and a survey of sources concerning his life is provided in W. R. Lefanu, A Bio-Bibliography of Edward Jenner (London, 1951). All later biographical accounts of Jenner have been based on John Baron, The Life of EdwardJenner (London, 1827).

Jenner has also been the subject of criticism by anti-vaccinationists. E. M. Crookshank, History and Pathology of Vaccination, 2vols. (London, 1889); and Charles Creighton, Jenner and Vaccination (London, 1889), are writings of this order. There is no modern detailed biog-raphy of Jenner and his life awaits critical reexamination. The rapid development of immunobiology gives an ever- increasing historical interest to his work.

Leonard G. Wilson

JENNER, EDWARD

Edward Jenner (1749–1823) was a British family doctor who practiced throughout his life in the village of Berkeley, Gloucestershire. He apprenticed for two years with John Hunter, then the preeminent medical teacher in Britain, but never took any examinations to obtain a medical degree. Instead, he purchased a medical degree from a Scottish university and later applied for and was granted an M.D. degree from Oxford University. He was keenly interested in all aspects of natural history, and he wrote a notebook describing the habits and habitats of birds in his district. A man with considerable intellectual and leadership qualities, he also founded a local medical society that survived for many generations.

At the time of Jenner's birth, smallpox was an ever present threat to life and health. When it did not kill outright, it often left a legacy of disfiguring facial pockmarks, and if it affected the eyes it caused blindness.

The practice of variolation—inoculation into the skin, or insufflation into the nose, of dried secretions from a smallpox bleb—was invented in China around 1000 c.e. and spread along the silk route, reaching Asia Minor some time in the seventeenth century. Lady Mary Wortley Montague, wife of the British ambassador to the Ottoman Empire, described the practice, also called ingrafting, in a letter to her friend Sarah Chiswell dated April 1, 1717, and imported the idea to England when she returned home. By the time Jenner was a child, ingrafting had become widespread among educated English families as a way to provide some protection against smallpox. If virulent smallpox virus had happened to survive in the batch of secretions used, however, the procedure sometimes caused severe illness and even occasional fatalities. This was generally considered to be a risk worth taking, as it was substantially less than the risk of death or disfigurement posed by epidemic smallpox itself.

Jenner knew the popular belief in Gloucester-shire that people who had been infected with cowpox, a mild disease acquired from cattle, did not get smallpox. He reasoned that since smallpox in mild form was transmitted by variolation, it might be possible to similarly transmit cowpox. He made many observations, starting in 1778, and a smallpox outbreak in 1792 provided him with the opportunity to confirm his belief that persons previously infected with cowpox did not get smallpox. In 1796 he began a courageous and unprecedented experiment—one that by modern standards would be considered unethical—that would have an incalculable benefit for humankind. He inoculated a boy, James Phipps, with secretions from a cowpox lesion. Over the following months he inoculated others, most of them children, inoculating twenty-three in all. They all survived unharmed, and none got smallpox. In 1798, Jenner published his results in An Inquiry into the Causes and Effects of the Variolae Vaccinae. His findings rank among the most important medical discoveries of all time.

The importance of Jenner's work was immediately recognized, and although there were skeptics and vicious antagonists, vaccination programs soon began. At first, these programs were conducted more vigorously in some European nations than in Britain. In 1802, Jenner was rewarded by Parliament with a grant of £10,000, and in 1807 with a further £20,000, but he was not otherwise honored in his own country. In France and other European nations, however, his achievement was more suitably commemorated.

In due course, Jenner's discovery led to a successful campaign by the World Health Organization to eradicate smallpox. In 1980, the World Health Assembly proclaimed that smallpox, one of the most deadly scourges of mankind, had been eradicated. At the beginning of the new millennium, samples of the smallpox virus survive in secure biological laboratories in several countries, but thanks to Edward Jenner, this terrible disease need never again take a human life.

John M. Last

Bibliography

Jenner, E. (1798). An Inquiry into the Causes and Effects of the Variolae Vaccinae. Reprint. Birmingham, AL: Classics of Medicine Library, 1978.

LeFanu, W. R. (1951). A Bio-bibliography of Edward Jenner, 1749–1823. London: Harvey and Blythe.

JENNER, EDWARD

JENNER, EDWARD (1749–1823), English physician.

Edward Jenner is commonly regarded as the simple country doctor who, by recognizing the value of prudential folk-knowledge, and by acting with selfless determination to promote his "discovery" of vaccination, started the long march toward the ultimate eradication of smallpox, as yet the only disease to have been effectively eliminated through human endeavor. However, since the 1980s some historical scholarship has sought to explode this myth of heroic individualism by emphasizing the broader medical context in which Jenner operated and by demonstrating how the ultimate acceptance of vaccination was due as much to the effectiveness of his social networks and the efforts of his supporters as to any intrinsic "scientific" superiority over alternative practices.

early life and education

Edward Jenner was born in Berkeley, Gloucestershire, on 17 May 1749 to Sarah Jenner (née Head) and her husband, Stephen, the local vicar. He was the eighth of nine children, and one of six to survive childhood. In October 1754, when Edward was just nine years old, his mother died during childbirth; his father followed just two months later. Orphaned, Edward was cared for by his sisters.

In 1764 Jenner was apprenticed to an apothecary in Chipping Sodbury. Six years later he traveled to London to perfect his knowledge of anatomy and surgery. In the metropolis, the simple country surgeon of legend assimilated himself into a social network that encompassed some of the most influential natural philosophers of the late Enlightenment, including the surgeons John Hunter (1728–1793), Everard Home (1756–1832), and Henry Cline (1750–1827), and the botanist Joseph Banks (1743–1820).

In 1772 Jenner returned to Berkeley to practice as a surgeon-apothecary, remaining there for much of the rest of his life. In March 1788, at the age of thirty-eight, he married Catherine Kingscote (1760/1–1815), the daughter of a wealthy local gentry family. During their relatively short life together they had three children, Edward (1789–1810), Catherine (1794–1833), and Robert Fitzharding (1797–1854).

Jenner entertained a wide range of intellectual interests in poetry, botany, and natural history and was elected to the Royal Society in 1789. The importance of sociability to the practice of medicine in this period is evident in his reputation as a fine host and in the names of two local bodies of which he was a member, the Convivio-Medical Society of Alveston and the Medico-Convivial Society, which he helped to establish at Rodborough in 1788.

vaccination

Smallpox, a disfiguring and potentially lethal disease, was virtually endemic in eighteenth-century Britain and was the subject of considerable medical and public debate. The practice of inoculation, by which matter from the pustule of a smallpox victim was introduced into the skin of a healthy person to produce a mild immunizing infection, had been introduced into Britain by Lady Mary Wortley Montagu in 1721. Inoculation had received the support of the Royal College of Physicians in 1754 and was a fairly widespread practice by the end of the eighteenth century. Inoculation had its problems, however. Although rare, it was not unknown for inoculated persons to develop full-blown smallpox. Fears were also expressed that it could lead to the outbreak of an epidemic among the uninoculated population.

Jenner seems to have long been aware of the idea, prevalent in the rural areas of western England, that those who contracted cowpox, a similar, but much milder and more localized disease present in cattle, never caught smallpox. He had discussed the matter with friends and colleagues in the early 1770s but it was not until the 1790s that he undertook preliminary investigations. In 1796 Jenner (now a physician, courtesy of the University of St. Andrew's) recorded his first attempt to inoculate using cowpox matter, which was taken from the pustule of a milkmaid, Sarah Nelmes (who had allegedly contracted it from a cow called Blossom), and given to a boy named James Phipps. Jenner subsequently inoculated Phipps with smallpox, but the boy remained unaffected, suggesting that cowpox had indeed conferred immunity to the disease. Jenner intended to publish his findings in the Philosophical Transactions but was discouraged from doing so by Home and Banks. He thus undertook further investigations before publishing his Inquiry into… Cowpox (1798). In this and subsequent publications he asserted that cowpox could offer lifelong immunity to smallpox and could be serially transferred from arm to arm.

Vaccination (a term deriving from the Latin vacca for "cow"), excited much interest, but also aroused a great deal of controversy among those who were attached to the existing practice of inoculation and those who were opposed, morally and/or intellectually, to the introduction of pathological animal matter into the human body. Despite this, however, Jenner's theories gained ground, not least because of his social connections.

He enjoyed the support of many influential metropolitan practitioners and secured the patronage of George III (r. 1760–1820), Queen Charlotte, and the Prince of Wales (who, as George IV, made him physician-extraordinary in 1821). Vaccination was officially adopted by the army and navy, and in 1802 Jenner received a parliamentary grant of £10,000, followed in 1807 by a further award of £20,000, to compensate him for the fact that he had made no direct profit from his researches.

Jenner's fame was in part a combination of his own talent for self-promotion and the mythologizing activities of his supporters, both during his life and after his death. In 1803 they founded the Royal Jennerian Society (reformed as the National Vaccine Establishment in 1809) to promote the practice of vaccination. In addition, paintings were commissioned, medals struck, and statues built, all of which contributed to the image of Jenner as a man of singular genius.

Edward Jenner died from a stroke at his house in Berkeley on 26 January 1823. By this time vaccination was an established practice in Britain, and in 1840 it was made freely available to all by law. This was followed in 1853 by legislation making it compulsory for all infants. Nonetheless, it continued to arouse controversy well into the twentieth century and was opposed by those who objected to it on moral or religious grounds ("conscientious objection" was permitted by an act of 1898), those who objected to the legislative establishment of medical professional authority, and others who saw it as an infringement of the rights of the individual.

See alsoDisease; Public Health; Science and Technology; Smallpox.

bibliography

Baxby, Derrick. Jenner's Smallpox Vaccine: The Riddle of Vaccinia Virus and Its Origin. London, 1981.

Bazin, Hervé. The Eradication of Smallpox: Edward Jenner and the First and Only Eradication of a Human Infectious Disease. Translated by Andrew and Glenise Morgan. London, 2000.

Fisher, Richard B. Edward Jenner, 1749–1823. London, 1991. A good general biography.

Le Fanu, William. A Bibliography of Edward Jenner. 2nd rev. ed. Winchester, U.K., 1985. A thorough bibliography of Jenner' writings.

Razzell, Peter E. Edward Jenner's Cowpox Vaccine: The History of a Medical Myth. 2nd ed. Firle, 1980. An interesting revisionist account.

Saunders, Paul. Edward Jenner, the Cheltenham Years, 1795–1823: Being a Chronicle of the Vaccination Campaign. Hanover, N.H., 1982.

Michael Brown

Jenner, Edward (1749-1823)

English physician

Edward Jenner discovered the process of vaccination , when he found that injection with cowpox protected against smallpox . His method of immunization via vaccination ushered in the new science of immunology .

Jenner was born in Berkeley, England, the third son and youngest of six children of Stephen Jenner, a clergyman of the Church of England. He was orphaned at age five and was raised by his older sister, who was married to a clergyman. When Jenner was thirteen years old, he was apprenticed to a surgeon. Then in 1770, he moved to London, England, to work with John Hunter (1728 – 1798), an eminent Scottish anatomist and surgeon who encouraged Jenner to be inquisitive and experimental in his approach to medicine. Jenner returned to Berkeley in 1773, and set up practice as a country doctor.

During and prior to Jenner's lifetime, smallpox was a common and often fatal disease worldwide. Many centuries before Jenner's time, the Chinese had begun the practice of blowing flakes from smallpox scabs up the nostrils of healthy persons to confer immunity to the disease. By the seventeenth century, the Turks and Greeks had discovered that, when injected into the skin of healthy individuals, the serum from the smallpox pustule induced a mild case of the disease and subsequent immunity. This practice of inoculation, termed variolation, reached England by the eighteenth century. However, it was quite risky as those who were inoculated frequently suffered a severe or fatal case of smallpox. Despite the risk, people willingly agreed to inoculation because of the widespread incidence of smallpox and the fear of suffering from terribly disfiguring pockmarks that resulted from the disease.

As a young physician, Jenner noted that dairy workers who had been exposed to cowpox, a disease like smallpox only milder, seemed immune to the more severe infection. He continually put forth his theory that cowpox could be used to prevent smallpox, but his contemporaries shunned his ideas. They maintained that they had seen smallpox victims who claimed to have had earlier cases of cowpox.

It became Jenner's task to transform a country superstition into an accepted medical practice. For up until the mid – 1770s, the only documented cases of vaccinations using cowpox came from farmers such as Benjamin Jesty of Dorsetshire who vaccinated his family with cowpox using a darning needle.

After observing cases of cowpox and smallpox for a quarter century, Jenner took a step that could have branded him a criminal as easily as a hero. On May 14, 1796, he removed the fluid from a cowpox lesion from dairymaid Sarah Nelmes, and inoculated James Phipps, an eight-year-old boy, who soon came down with cowpox. Six weeks later, he inoculated the boy with smallpox. The boy remained healthy. Jenner had proved his theory. He called his method vaccination, using the Latin word vacca, meaning cow, and vaccinia, meaning cowpox. He also introduced the word virus.

The publication of Jenner's An Inquiry into the Causes and Effects of the Variolae Vaccinae set off an enthusiastic demand for vaccination throughout Europe. Within 18 months, the number of deaths from smallpox had dropped by two-thirds in England after 12,000 people were vaccinated. By 1800, over 100,000 people had been vaccinated worldwide. As the demand for the vaccine rapidly increased, Jenner discovered that he could take lymph from a smallpox pustule and dry it in a glass tube for use up to three months later. The vaccine could then be transported.

Jenner was honored and respected throughout Europe and the United States. At his request, Napoleon released several Englishmen who had been jailed in France in 1804, while France and Great Britain were at war. Across the Atlantic Ocean, Thomas Jefferson received the vaccine from Jenner and proceeded to vaccinate his family and neighbors at Monticello. However, in his native England, Jenner's medical colleagues refused to allow him entry into the College of Physicians in London, insisting that he first pass a test on the theories of Hippocrates and Galen. Jenner refused to bow to their demands, saying his accomplishments in conquering smallpox should have qualified him for election. He was never elected to the college. Jenner continued his medical practice, as well as collecting fossils and propagating hybrid plants in his garden, until his death from a stroke at the age of 73.

Nearly two centuries after Jenner's experimental vaccination of young James, the World Health Organization declared endemic smallpox to be eradicated.

See also Antibody and antigen; Antibody formation and kinetics; Immunity, active, passive and delayed; Immunity, cell mediated; Immunity, humoral regulation

Jenner, Edward

Edward Jenner (1749-1823) was a pioneer in the study of viruses and immunization against diseases. His work has been built upon by many successors who have discovered new vaccinations to reduce suffering and death, particularly for children.

Jenner was born in Berkeley, England, the youngest of six children born to Stephen Jenner, a clergyman of the Church of England. Jenner's father died when he was only five years old, and he was raised by his older brother, who was also a clergyman.

In agreement with the practice at the time, eight-year-old Jenner was forced to fast (not eat for long periods), had blood drawn from him in a practice called "bleeding," and was injected with smallpox (in the hope that the injection would prevent the disease).

When Jenner was thirteen years old, he was apprenticed (became an assistant in training) to a surgeon. Then in 1770, he moved to London, England, to work with John Hunter (1728-1798), a famous Scottish anatomist and surgeon who encouraged Jenner to be curious and experimental in his approach to medicine. Jenner returned to Berkeley in 1773, and set up practice as a country doctor. His curiosity led him to conduct his own research to help his rural patients.

Smallpox

Up until Jenner's time, smallpox was a common and often fatal disease worldwide. It caused high fevers and ugly pockmark scars, like those of chicken pox, only these scars could disfigure a person for life.

Many centuries before Jenner's time, the Chinese had begun the practice of blowing flakes from smallpox scabs up the nostrils of healthy persons to produce immunity to the disease. By the seventeenth century, the Turks and Greeks had discovered that, when injected into the skin of healthy individuals, the serum from the smallpox blister produced a mild case of the disease and subsequent immunity.

The practice of inoculation reached England by the eighteenth century. It was quite risky, since those who were inoculated frequently suffered a severe or fatal case of smallpox. Despite the risk, people willingly agreed to inoculation because of the widespread incidence of smallpox and the fear of suffering terrible disfigurement.

Jenner's Experiments

As a young physician, Jenner noticed that dairy workers who had been exposed to cowpox, a disease like mild smallpox, seemed immune to the more severe infection. Jenner continually put forth his theory that cowpox could be used to prevent smallpox, but his fellow physicians shunned his ideas. They maintained that they had seen smallpox victims who claimed to have had earlier cases of cowpox, so that cowpox must not give immunity. It became Jenner's task to transform a country superstition into an accepted medical practice.

After many years of observing cases of cowpox, Jenner took a step that could have branded him a criminal as easily as a hero. On May 14, 1796, he removed the fluid of a cowpox blister from dairymaid Sarah Nelmes, and inoculated James Phipps, an eight-year-old boy who soon came down with cowpox. Six weeks later, he inoculated the boy with smallpox. The boy remained healthy, and Jenner had proved his theory. Jenner called his method "vaccination," using the Latin word "vaccinia," meaning "cowpox."

The publication of Jenner's An Inquiry into the Causes and Effects of the Variolae Vaccinae set off an enthusiastic demand for vaccination throughout Europe. Within 18 months, the number of deaths from smallpox had dropped by two-thirds in England. By 1800, 100,000 people had been vaccinated worldwide. As the demand for the vaccine rapidly increased, Jenner discovered that he could take lymph from a smallpox pustule and dry it in a glass tube for use up to three months later. The vaccine could then be transported.

Jenner became famous throughout Europe and the United States. Across the Atlantic Ocean, Thomas Jefferson received the vaccine from Jenner and proceeded to vaccinate his family and neighbors at Monticello. In his native England, however, Jenner's medical colleagues refused to allow him entry into the College of Physicians in London, insisting that he first pass a test on the theories of the ancient Greek physicians, Hippocrates (460-377 b.c) and Galen (a.d. 130-200). Jenner refused to bow to their demands, saying his accomplishments in conquering smallpox should have qualified him for election. He was never elected to the college.

Jenner continued to live in his country home and practice medicine in the years after his discovery. He also pursued his interest in birds and wrote papers on their behavior until his death in 1823. His work had far-reaching effects, inspiring Louis Pasteur (1822-1895) in his research on the causes of disease, thus leading to vaccines for other serious illnesses. And today, thanks to Jenner's curiosity and perseverence, smallpox has been largely eradicated (erased).