Isolation and quarantine are public health practices used to protect the public by preventing exposure to people who have or may have a contagious disease.
Isolation separates sick people with a contagious disease from people who are not sick.
Quarantine separates and restricts the movement of people who were exposed to a contagious disease to see if they become sick. These people may have been exposed to a disease and do not know it, or they may have the disease but do not show symptoms.