Communicable diseases spread from one person to another or from an animal to a person. The spread often happens via airborne viruses or bacteria, but also through blood or other bodily fluid. The terms infectious and contagious are also used to describe communicable disease. In this section, learn about coordinated efforts to combat a few of the most serious communicable diseases on a global level. Click here for the IU policy for Managment of Infectious and Communicable Disease.