Germ theory, in medicine, the theory that certain diseases are caused by the invasion of the body by microorganisms, organisms too small to be seen except through a microscope.
Pasteur’s discovery that bacteria are responsible for spoiling
wine led naturally to his hypothesis in 1857 that microorganisms
are also responsible for diseases. This idea came to be known
as the germ theory of disease. But he could not prove it experimentally.
Koch’s Postulates, which provided scientists
with a method of establishing the germ theory of
disease, are as follows:
1. The specific causative agent must be found in every
case of the disease.
2. The disease organism must be isolated in pure culture.
3. Inoculation of a sample of the culture into a healthy,
susceptible animal must produce the same disease.
4. The disease organism must be recovered from the
inoculated animal.
14 апр 2020
