Koch postulates on the association between infectious pathogen and disease
| Postulate . | Description . |
|---|---|
| 1 | The parasite occurs in every case of the disease in question and under circumstances which can account for the pathologic changes and clinical course of the disease. |
| 2 | The parasite occurs in no other disease as a fortuitous and nonpathogenic parasite. |
| 3 | After being fully isolated from the body and repeatedly grown in pure culture, the parasite can induce the disease anew. |
| 4 | The parasite should be able to be reisolated from the experimentally infected host. |
| Postulate . | Description . |
|---|---|
| 1 | The parasite occurs in every case of the disease in question and under circumstances which can account for the pathologic changes and clinical course of the disease. |
| 2 | The parasite occurs in no other disease as a fortuitous and nonpathogenic parasite. |
| 3 | After being fully isolated from the body and repeatedly grown in pure culture, the parasite can induce the disease anew. |
| 4 | The parasite should be able to be reisolated from the experimentally infected host. |