Review Article
S Ravikanth Vasudev
Abstract
A disease or medical and an abnormal condition happened to the body or mind. It causes pain, dull feeling and lastly death. It includes: parts of the body being hurt, not having the usual abilities, medical problems or organ malfunction, microbial infections, health issues, having pain or bad symptoms, unusual body shapes. The study of disease is called pathology. Disease can be described as a medical condition associated with particular symptoms and signs. It can be caused by external factors like pathogens, or caused by internal malfunctions mainly the immune system such as an immunodeficiency, or a hypersensitivity such as allergies and autoimmunity. Diseases are broadly classified to any abnormal condition that causes pain, dysfunction, distress, or death to the person affected with similar problems. It includes injuries, disabilities, disorders, syndromes, infections, isolated symptoms, deviant behaviours, and atypical variations of structure and its function and for others these may be considered as distinguishable categories. Diseases can affect people not only physically and mentally, as living with a disease will alter the affected person's thinking ability. Death caused by disease are often natural. Diseases are categorised into four main types: infectious diseases, deficiency diseases, genetic diseases and physiological diseases. Diseases can be classified as contagious and non-contagious. The fatal diseases in humans are HIV, Coronary Artery Disease, Chronic Obstructive Pulmonary Disease and cancer.