Legends of Microbiology and Infectious Diseases - Louis Pasteur

French chemist Louis Pasteur (1822-1895) has to beHis work in the silkworm industry was an important
ranked up there as one of the greatest contributorsstep in proving the germ theory of disease.
to the areas of microbiology and infectious diseases.Alcohol fermentation and Pasteurization
A painter and a teacher, Pasteur studied chemistry inHe discovered that carefully selected yeasts made
his spare time which eventually led to professorshipsgood wine, but that mixtures of other
at several French universities and contributions to themicroorganisms competed with the yeast for sugar
wine and silkworm industries.and made the wine taste oily and sour. His work in
Refuting spontaneous generationthe wine industry later lead to his namesake method
The famous "swan necked" flask experiment thatcalled pasteurization. This technique of heating the
Pasteur used in refuting spontaneous generationliquid that spoils easily, milk for example, heated to kill
worked like this: a fermentable juice was placed in amost bacteria and molds already present within them.
"swan neck" flask, and after sterilization the neckRabies
was heated and drawn out as a thin tube taking aHe did a lot of work in the field of vaccines, but he is
gentle downward then upward arc, resembling themost well known for his work with rabies. He used
neck of a swan. The end of neck was then sealed.dried spinal cord from rabbits infected with the
As long as it was sealed, the contents remaineddisease. He tested it on animals with success but
unchanged.wanted to test it on a human.
If the flask was opened by nipping off the end ofIn 1885, a 9 year old boy who was severely mauled
the neck, air could enter the flask, but the microbesby a rabid dog and his mother showed up to
and dust could not reach the liquid, being trapped inPasteur's lab. The boy, who was doomed to die the
the curved neck of the flask, which remained sterilehorrible death from rabies, was the first person to
despite exposure to air.get immunized against rabies. He survived and
Silkwormsremained in good health for the rest of his life.
While studying silkworms, he discovered severalPasteur became a legend as newspapers from
diseases that were killing off the silkworms in thearound the world reported this and others saved by
cocoon and damaging the silk industry. He was ablehis rabies vaccine.
to examine the worms microscopically and used onlyThe list could go on and on with Louis Pasteur. He
uninfected worms for breeding. He taught silkwormlater became director of the famous Pasteur
farmers how to detect infected worms with aInstitute in 1894. He died the next year as a national
microscope so they could select disease free worms.hero.