Fuente: WIPO "organic farming" A diagnostic test is provided for testing for spongiform encephalopathy and other demyelinating conditions in mammals such as BSE in cattle, and MS or CJD in humans, by assaying antibodies present in the mammal which bind to an Acinetobacter species containing an antigenic peptide which exhibits molecular mimicry of a mammalian myelin peptide, e.g. one having the sequence ISRFAWGEV. The test antigen used may be whole Acinetobacter or an antigenic having a sequence present therein, or a prepared or synthetic version of such peptide. The preferred assay is directed to IgA antibodies. Sera of animals or patients having the disease usually register antibody levels at least about two standard deviations above that of healthy control sera.