A communicable disease is defined as an illness which is caused by a specific infectious agent or its toxic products, and which arises through transmission of that agent or its products from a reservoir to a susceptible host. Such transmission can be either direct, as from an infected person or animal, or indirect, through the agency of an intermediate plant or animal host, vector, or the inanimate environment. They advocated for laws to pasteurize milk, assure pure food and prevent tuberculosis. The Communicable Disease Division is known as Epidemiology and Disease Control.
Epidemiology is the study of the occurrence of disease in a human population.
The term is derived from the Greek words, epi meaning on or upon, demos meaning people, and logos meaning the study of. Epidemiology had its beginning with the studies of the great epidemic diseases such as bubonic plague, cholera, and smallpox which occurred in waves and which were characterized by high mortality rates. As the science advanced, it was applied to the study of disease in the broadest sense of the word, to include heart disease, accidents, diabetes and cancer among many others. In Maryland there are approximately 50 reportable communicable diseases and conditions. At this site are facts about each of the reportable diseases.