The word vaccine comes from the Latin vaccinia, which means belonging to or relating to cows. It is an inoculation technique developed by the English doctor Edward Jenner at the end of the 18th century.
Vaccines work according to a principle that by introducing a controlled sample of a virus into a living organism, the organism itself develops the necessary antibodies to resist possible subsequent exposure to this virus, creating what is known as as immunity.
The discovery of vaccines
Jenner made his finding by observing that farm workers who had contact with cattle for any reason were not affected by smallpox, a long-standing disease that by then killed hundreds of thousands of people around the world. the world.
What actually happened was that these people, when handling cattle infected with a specific type of smallpox that only attacked their species, developed antibodies in their own body that prevented contagion.
After a series of experiments in which cowpox was inoculated into humans, Jenner confirmed the truth of his hypothesis. However, he himself had no idea what it was that protected people from the disease, since at the time it was not yet known what viruses were.
Almost a hundred years after Jenner's discovery, the French chemist Louis Pasteur developed and expounded his theory of infectious diseases, in which he showed that these diseases were transmitted by small microorganisms called germs. p>
Starting in 1880, the year in which Pasteur made and published his findings, six different vaccines against infectious diseases such as anthrax, cholera, tetanus, rabies, diphtheria and chronic diarrhea were developed in a short period of time. < /p>
Undoubtedly Pasteur was a scientist who decisively contributed to the development of modern vaccines and in fact he was the one who gave them his name, in homage to the experiments with cowpox carried out by his predecessor Jenner a century ago.
The development of new vaccines
Already in the 20th century, research based on Pasteur's experiments and his assistant Charles Chamberland allowed the development of a series of vaccines against diseases that had afflicted humanity for many years and even centuries. < /p>
This is how vaccines against measles, rubella, tuberculosis, hepatitis B or polio were successively discovered, significantly improving the health conditions of millions of people.
In the case of polio, a disease caused by the so-called poliovirus, it is an infection that mainly affects children and causes paralysis and muscle atrophy. It would be in the mid-1950s when the North American Jonas Edward Salk discovered the first injectable vaccine, later improved by the virologist Albert Bruce Sabin and administered exclusively orally.
Importance of vaccinations
Currently there are a large number of scientifically proven vaccines that are applied mainly to children at an early age, according to established vaccination schedules.
Thanks to them, the human immune system is strengthened and produces complete immunization against various diseases, which helps save two to three million lives worldwide annually, according to calculations by the World Health Organization .
Although in very few cases vaccines can cause adverse reactions, such as mild fevers and muscle aches in the area of application, their benefits are unquestionable and represent an enormous achievement for humanity in the fight against deadly infections of viral origin or bacterial