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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Germ theory of disease was introduced by: March 2013
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The correct answer is  Ans. D i.e. John Snow Germ theory of disease It refers to the discovery in the late 19th century that some infectious diseases are caused by microorganisms, small organisms too small to see without magnification, that invades the host. The theory supplanted earlier explanations for disease such as miasma theory.