Koch's Postulates

Koch's Postulates

1. 1.

   • Organism must be found with disease
     • Constantly, within others in population
     • Should not be found in healthy organisms

2. 2.

   • Suspected causative microbe
     • Isolate from diseased organism
       • Grow in pure culture
       • streaking (smearing) of agar plates
         • Use of selective agars

3. 3.

   • introduced causative microbe
     • Should infect pure culture
       • Should show similar symptoms
         • from original disease

4. 4.

   • Same pathogen must be re-isolated
     • Must be similar to the original
       • Shows identical symptoms?
     • In another pure culture