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Louis Pasteur was born in 1822. He was a prominent French chemist, one of the founders of modern microbiology.
His research work helped much to establish the field of bacteriology. In his early years Pasteur devoted his energies to the discovery of microorganisms in wine and beer production. He introduced the idea of heat sterilization (pasteurization) for these products and milk too.
In later life he became interested in hydrophobia. Working in this field he developed the principle that viral pathogenic properties could be attenuated by passing the virus through the body of a proper animal. On the basis of these observations he developed a vaccine for hydrophobia.
Continuing his investigation L. Pasteur discovered the method to prevent some infectious diseases by introducing attenuated causative agents. This method is known as vaccination. It has helped to fight against many infectious diseases.
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In later life he became interested in _______.