Question

Koch's postulates established criteria for proving that a specific organism causes a specific disease. Which of the following is NOT one of the criteria given by Koch's postulates? 1. The pathogen isolated from a pure culture must cause the disease in a healthy lab animal. 2. The pathogen must be isolated from inoculated animals and must be different from the original organism. 3. The pathogen must be isolated from the diseased host and grown in pure culture. 4. The same pathogen must be present in every case of the disease.

Answer 1

2. The pathogen must be isolated from inoculated animals and must be different from the original organism.

Step-by-step explanation:

Koch postulates says that every disease is caused by a pathogen. That pathogen can be isolated from the host and can be grown in pure culture. If this pure culture is inoculated into a healthy host than it must cause the disease in that host. The same pathogen can be again isolated from the second host.

Therefore according to Koch's postulated the pathogen must be isolated from the inoculated animals and must be the same as the original organism therefore the second option is wrong.