Pasteur believed that germs, just as those that caused fermentation, could also be causing disease. With the support of other scientists and collaborators, he was able to isolate several disease causing bacteria, cholera (with Robert Koch) and small pox (work originally done by Edward Jenner), among several others. While working with cholera in chicken, Pasteur helped set the foundation for the idea of vaccinations; this had been proposed by others earlier. That a mild form of the virus or bacteria induces the creation of antibodies in the host. When infected by a virulent form of the virus or bacteria, the antibodies created in the system can destroy the infecting agents thereby protecting the host. Pasteur's work influenced the creation of vaccinations.

After successfully using it in the cure of cholera, small pox and several other diseases, Pasteur used this idea in identifying a cure for rabies. After several attempts at isolating the rabies virus, Pasteur discovered (from how the disease manifested) that the virus targeted the neurological system including the spinal chord. He injected hosts with the crushed spinal matter of rabbits which he used to incubate the virus extracted from the neural systems of dogs. Pasteur was also known for taking risks. He injected a little boy who had suffered a dog bite and was showing the early signs of the fatal disease. The boy survived. Since Pasteur had no medical license to practice, he almost set himself up for jail time.

Though there is some controversy as to the exact contribution of Louis Pasteur in the isolation of the anthrax virus and the development of a vaccine that salvaged the sheep industry, there is no doubt that he was a major player in this.

Louis Pasteur, pursing the idea the causative agents of disease came from without and not within realized that medical practitioners might be carriers and spreaders of germs. He became a strong advocate...

He believed that all instruments had to be clean and heated to more than a thousand degrees before use. Along with Joseph Lister, another advocate of clean conditions, several thousand lives with might have been lost despite successful surgery (due to unhygienic conditions) were saved.
Pasteur's influence was every where. He took his notions of germ theory to horticultural practices. The silk industry today owes its thanks to him. Silk worms under certain conditions either died within the cocoon or did not produce silk. Pasture closely infected the caterpillars and discovered certain disease conditions which he identified as bacterial infections. Pasteur identified two bacteria. He taught the silk specialists how to spot the infected insects and separate them from the silk-producing process. The silk industry, much like the wine and milk industry had a better control over the quality of its processes and products.

Plagued by ill health following a paralytic attack at the age of 46, Pasteur continued to work tirelessly till his death in September 22, 1895. He is buried at the Institut Pasteur. In an interesting irony, the boy who Pasteur cured from rabies eventually worked at the Institut Pasteur as a gate keeper. When forced to desecrate Pasteur's tomb by invading Nazis during World War II, the boy, Joseph Meister opted to take his own life. (Cohn, 1996)

Bibliography

Cohn, David V. (1996, February 11). The Life and Times of Louis Pasteur. Retrieved. March 17, 2009 at http://louisville.edu/library/ekstrom/special/pasteur/cohn.html

Debre, P.; E. Forster (1998). Louis Pasteur. Baltimore, MD: Johns Hopkins University Press.

Hart, Michael H. (1992). The 100: A Ranking of the Most Influential Persons in History. Citadel Press. pp. pp.60-61.

Morris, D.; Abel, E. (2002). Stereochemistry. New York: John Wiley and Sons.