Edward Jenner

DNL oral n°2

Edward JENNER

        Hi, today I chose to talk to you about Edward Jenner because I love medical research, so knowing how a vaccine is implemented is exciting for me.  

 So Edward Jenner is an English scientist and physician who studied natural sciences in his home environment in Berkeley, England.

He was the first doctor to introduce and scientifically study the smallpox vaccine and is considered the "father of immunology". But before I elaborate on his research, I'll tell you a little more about him.

Edward Jenner was trained at Chipping Sodbury at the age of fourteen by Mr. Ludlow, a surgeon. William Osler, a Canadian physician, reports that Jenner was a student to whom Hunter, a renowned surgeon, repeated a very famous medical saying characteristic of the Age of Enlightenment: "Don't believe, try.

Edward Jenner was soon followed by men famous for advancing the practice and institutions of medicine. He first established himself as a general practitioner and surgeon in his hometown and in 1792 received his medical degree from the University of St. Andrews.

Now that you know a little bit more about Edward Jenner, we can move on to what I think is the most interesting part, his research on the smallpox vaccine.

In the 18th century, smallpox was feared because one-third of people who contract it die from it, and those who survive are usually disfigured. By 1769 and in the years that followed, several people in England and Germany had successfully experimented with the possibility of using a benign disease, vaccinia, as a means of immunizing humans against smallpox. In 1769, for example, Dr. Jobst Bose, a German physician, showed that the milk of cows suffering from vaccinia could be used as protection against smallpox.

But it wasn't until about 20 years later, after Jenner's work, his first experiments, that the technique was generally understood.

Based on the common observation that milkers don't usually get smallpox, Jenner theorized that the contents of the blisters of milkers who had contracted vaccinia (a disease similar to smallpox, but much less virulent), protected the milkers from smallpox, but this was not Edward Jenner's original theory.

On May 14, 1796, Jenner tested his theory by inoculating James Phipps, an eight-year-old boy, with the contents of vaccine ampoules from the hand of Sarah Nelmes, a milker who had contracted vaccinia from a cow; this inoculation caused fever and general malaise, but no serious disease. Jenner hypothesized that infection with vaccinia could confer immunity to smallpox. So if variolation doesn't trigger infection, that's proof that Phipps is immune to smallpox.

 Later he repeated the experiment but this time he inoculated the young boy using the variolization technique and no disease appeared. Jenner's hypothesis is therefore validated. He continued his research and after improving the method, he published a study on about twenty cases. The medical community studied his findings for some time before accepting them. In 1840, the British government banned variolization and encouraged free vaccination. Subsequently, the smallpox vaccine was accepted throughout Europe. Unfortunately, he did not see his vaccine spread throughout Europe or even Great Britain because he died a few years earlier, in 1823, from a stroke.

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