In 1849 Snow published a small pamphlet “”On the Mode of Communication of Cholera”” where he proposed that the “”Cholera Poison”” reproduced in the human body and was spread through the contamination of food or water. This theory was opposed to the more commonly accepted idea that Cholera, like all diseases, was transmitted through inhalation of contaminated vapors. Although he was awarded for this work, without the technology and knowledge that we have today, Snow had no way to prove his theory.