Control of diseases of silk worms
Development of vaccines against anthrax and rabies.
Discovery of streptococci
The germ theory of disease The complete establishment of the germ theory of disease depended on the work of a German scientist, Robert Koch (1843- 1910).
Major achievements of Robert Koch
1. 2. 3. 4 .
Discovery and use of solid medium in bacteriology Discovery of causative agents of tuberculosis and cholera. Koch’s phenomenon Koch’s postulates
Koch s postulates: proof of germ theory of disease A micro-organism can be accepted as a causative agent of an infectious disease only if the following conditions are satisfied.
The micro-organism should be found in every case of the disease and under conditions which explain the pathological changes and clinical features.
It should be possible to isolate the causative agent in pure culture from the lesion.
When such pure culture is inoculated into appropriate laboratory animal, the lesion of the disease should be reproduced.
It should be possible to reisolate the bacterium in pure culture from the lesion produced in the experimental animal.
Now a days additional postulate is mentioned i.e.