It is when a disease spreads quickly by nearby regions, although it does not last long if must affect many people. The origin of the word is Greek 949; 960; 953; 948; 951; 956; 953; 945; (epidemic temporary residence in a village), 949; 960; 953; (epi envelope, in) 948; 951; 956; 959; 962; (demos people, populated). The change of meaning comes from a Treaty of Hippocrates where named duration and permanence of disease in a population, and was taken by French scholars during the middle ages with current sense. See sindemia, pandemic, endemic.