There are four main types of disease: infectious diseases, deficiency diseases, hereditary diseases (including both genetic and non-genetic hereditary diseases), and physiological …

6 days ago · disease, any harmful deviation from the healthy structural or functional state of an organism, generally associated with certain signs and symptoms and differing in nature from …

Explore comprehensive guides on hundreds of common and rare diseases and conditions from the experts at Mayo Clinic.

Jun 1, 2025 · At first glance, the answer seems deceptively simple: disease is the presence of illness, of something going wrong within the body. But the deeper we probe into this …

DISEASE definition: 1. (an) illness of people, animals, plants, etc., caused by infection or a failure of health rather…. Learn more.

6 days ago · This page details respiratory illnesses from bacteria and viruses other than COVID-19, flu, and RSV. It also shows the latest emergency department trends for conditions that …

Most of us feel we have an intuitive grasp of the idea, reaching mentally to images or memories of colds, cancer or tuberculosis. But a look through any medical dictionary soon shows that …