Spanish priests arrive in Mexico at the end of the conquest to convert the Central American people to Christianity. The Priests live and work with the Aztec people and Historian, Elizabeth Baquedano believes that the shared living conditions enabled the virus to become more deadly. She describes how the Spanish Conquerors introduced a way of living and working known as Encomienda. It was an industrialised system of farming to produce wheat for European style bread. The Aztecs worked long hours in fields and grain stores, the chances of them coming into contact with infected rodents greatly increased.