Louis Pasteur was a French Scientist. He was not a doctor, or even a medical scientist. He became known throughout the world of medicine through research he was conducting on behalf of a brewing company, who were concerned about the lifespan of their beers. Pasteur believed that germs in the air may be the cause of the beer ‘going off’. This was an unusual theory as, at the time, people believed that germs were a product of disease and decay, rather than a cause of it.
Pasteur experimented with the fermentation process and soon realised that the germs were being created during the process. He proved this through experimentation. He warmed water and allowed it to bubble into the bend of a connecting pipe. After cooling the pipe was broken and decay set into the water very quickly. Many doctors were still sceptical however. By 1867 though, Pasteur was able to demonstrate unequivocally that there was a link between germs, decay and disease.
Pasteur’s discoveries led him to work more and more in the field of medical science and he later discovered a vaccine for Cholera, Anthrax and Rabies.