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Pathogenicity
Bacterial pathogenicity is its capacity to cause disease and the disease's severity. Pathogenicity depends on both the pathogen and the host. Bacterial virulence factors are important determinants of pathogenicity.
Koch's Postulates were derived to determine whether an organism is the cause of diease, or simply part of normal flora.
- The same organism must be found in all cases of a given disease
- The organism must be isolated and grown in pure culture
- Organisms from pure culture must reproduce disease when inocculated into a healthy susceptible animal
- The organism must then be isolated from the infected animal