Attempts to find the method we know today as "vaccination" have historically accompanied mankind, while devastating epidemics have terrorized and affected entire peoples. On May 17, 1749, Edward Jenner was born in Gloucester, England, a man who was destined to become the physician who would save the lives of millions of people through a great discovery. 

Edward Jenner, son of the town's vicar, suffered from smallpox as a child and it left lasting effects on his health. In 1761, young Edward moved to Sodbury and began his training as a surgeon and pharmacist under the village physician, Abraham Ludlow. In 1770, at the age of 21, Edward began his studies at St. George's Hospital in London.

During the 1790s, Jenner systematically sought ways to protect mankind from the disease that had nearly killed him in his childhood and was one of the most feared diseases of the time - in Europe alone, smallpox killed an estimated 60 million people in the 18th century alone. From time to time, an epidemic would break out, and because there was little knowledge and practice of hygiene, the disease spread easily through the filthy, overcrowded cities.

Despite the strong opposition of other physicians, Jenner tried to implement a method he had studied at St. George's Hospital, known as "variolization", which consisted of inoculating a healthy person with infected material. This process was introduced in London in 1721 by the wife of the English ambassador to Turkey, Lady Montangu, a woman of independent character who decided to inoculate her own children as proof of her confidence in the method. 

It was thanks to a popular belief that Jenner gradually came closer to his great discovery. He had earlier heard a cow milker named Sarah Nelmes make the following statement: "I will never have smallpox because I have had cowpox. I will never have a pock-marked face." As a country doctor, he began to closely observe and investigate cattle and domestic animals. And he realized that indeed people who milked cows and who were infected with smallpox, soon afterwards presented some pustules on their hands, however, when epidemics of human smallpox arrived, their families were infected, but they were not.