<p>A diagnostic sensor comprising means for detecting a ligand or antigen corresponding to abnormality or disorder as well as any of various pathogenic organisms existing in sites of living organism and/or humors of living organism and vapors from living organism and further comprising means for signal generation effected upon detection of any of the pathogenic organisms, antigen and ligand by the detection means, which diagnostic sensor upon detection of any ligand, antigen or pathogenic organism being the cause of odor emission in extraordinary condition, produces an electrical change to thereby attain detection of extraordinary condition.</p>
