Isolation: Separation for the period of communicability of infected persons in such places or under such conditions as prevent transmission of infectious agent to the susceptible. Quarantine: It is the limitation of movement of such well persons or animals exposed to communicable diseases for a period usually not longer than the longest incubation period of the disease to prevent effective contact with those not exposed. Segregation: It is the separation for special consideration, control of observation of some pa of a group of persons from others to facilitate control of communicable disease. Ref: Park 21st edition, page 110-111.