Medical Conditions and Illnesses
A disease is an abnormal condition affecting the body or an organism. It is often construed to be a medical condition associated with specific symptoms and signs.
It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune diseases.
In humans, "disease" is often used more broadly to refer to any condition that causes pain, dysfunction, distress, social problems, and/or death to the person afflicted, or similar problems for those in contact with the person.