““Koch’s postulates here: The same pathogen must be present in every case of a disease. The pathogen must be isolated from the diseased host and grown in a laboratory to show it is alive. The pathogen should be checked to confirm its purity and then injected into a healthy host (a laboratory animal). The injected pathogen must cause the same disease in the new host. The pathogen must be recovered from the new host and again grown in the laboratory. Some””
