Disease Etiology

The term "aetiology" in medicine describes the reason or causes of illnesses or pathologies. The term "idiopathic" refers to a condition for which there is no known cause. The "evil eye" may be implicated in traditional theories about the origins of sickness. Medieval European physicians tended to believe that illness was influenced by the atmosphere and used a miasmatic approach to disease genesis. Robert Koch established that the pathogenic bacterial species Mycobacterium tuberculosis, Bacillus anthracis, and Vibrio cholerae are responsible for the diseases tuberculosis, anthrax, and cholera, respectively. This led to the etiological discovery in medicine. Koch's postulates provide an overview of this line of reasoning and supporting data. But in the case of infectious diseases, proof of causation is restricted to specific cases that offer experimental proof of etiology.