What are Koch's postulates and why are they important?
Koch's postulates consist of four criteria designed to establish a causal relationship between a microbe and a disease:
1. The microorganism must be found in abundance in all organisms suffering from the disease, but should not be found in healthy organisms. 2. The microorganism must be isolated from a diseased organism and grown in pure culture. 3. The cultured microorganism should cause disease when introduced into a healthy organism. 4. The microorganism must be re-isolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.
These postulates were essential for the development of the germ theory of disease, which posits that microorganisms are the cause of many diseases. Although modern science has shown that not all diseases fit neatly into these criteria, Koch's postulates remain a cornerstone in the understanding of infectious diseases.
