The following pathogen does not satisfy "Koch's postulates" -

Koch postulates Robert Koch proposed a series of postulates that have been applied broadly to link many specific bacterial species with a particular disease. Koch's postulates are : The microorganism should be found in all cases of the disease in question and its distribution in the body should be in accordance with the lesions observed. The microorganism should be grown in pure culture in vitro (or outside the body of the host) for several generations. When such a pure culture is inoculated into susceptible animal species, the typical disease must result. The microorganism must again be isolated from the lesions of such experimentally produced disease.