Pasteur's phenomenal contribution in the fields of   microbiology and medicine can be listed as follows:

• Discovery of the Germ theory of disease, one of the most important discoveries in medical history.

• Discovery of the weakened forms of a microbe and its use as immunization against the more virulent forms.

• Recommended necessary changes in the hospital practices to control the spread of pathogens.

• Developer of techniques to vaccinate dogs against rabies and succeeded in treating humans bitten by rabid dogs.

• Developer of the technique of Pasteurization, to destroy the harmful microbes in perishable food products by heating, without spoiling the food.