What Are The 4 Types Of Diseases?

Diseases are abnormalities or a sense of discomfort caused in our body which can be localized to a particular area in the body or can cause weakness of the entire body. It can be caused due to various reasons, the study of the causes of diseases is known as etiology and the study of diseases is known as pathology. Once the body is attacked by a disease, it affects the normal functioning of the body, in worse cases can severely disable an individual from performing basic tasks such as breathing, walking, urinating etc. Our body exhibits signs of discomfort in the event of getting inflicted by any disease. These signs are called symptoms. In some diseases, symptoms can appear right from the time of inception while in some other medical conditions, symptoms show up significantly at a much later stage. There are 4 main types of diseases as listed below:

  • Infectious diseases
  • Hereditary diseases
  • Deficiency diseases
  • Physiological diseases

Infectious Diseases

These are the diseases caused by microorganisms such as fungi, virus, bacteria, protozoans or parasites. Microbes are usually found on our body but under unfavourable conditions may turn harmful. They can be communicated – from person to person, through insect bites or animals, from mother to fetus, ingestion of contaminated water or food, or exposure to infected air. Depending upon the infections, the symptoms vary. However, some commonly occurring symptoms are – Fever, fatigue, headache, cold, cough, vomiting etc. While some can be treated with home remedies and over-the-counter drugs, few other severe diseases require the attention of a doctor who prescribes vaccines and antibiotics.

Hereditary Diseases

They are caused by an irregularity in the genetic makeup of an individual, the abnormality can range from miniature up till major. It could be a distinct mutation in a particular base of the DNA of a single gene to a deformity of the whole chromosome which would involve the inclusion or exclusion of a set of chromosomes or the whole chromosome. Few of the genetic ailments are passed by the parents(in case they possess), while other genetic disorders can be acquired due to variations in the already existing gene or pool of genes. These mutations could be due to environmental exposure or may occur randomly. Examples of hereditary diseases are:

  • Cystic Fibrosis
  • Haemophilia
  • Thalassemia
  • Down’s syndrome
  • Huntington’s disease

Deficiency Disease

These are diseases caused due to insufficient supply of dietary elements, precisely, vitamins and minerals. The food we consume needs to have a good balance of all the nutrients. However, the modern diet lacks nutrients, causing deficiencies in the body. These deficiencies can be caused due to a lack of the following essential nutrients:

  • Calcium deficiency
  • Iodine deficiency
  • Iron deficiency
  • Vitamin B12 deficiency
  • Vitamin D deficiency
  • Magnesium deficiency
  • Vitamin A deficiency

Physiological Diseases

It is a disorder of the function of tissues or structure of organs and tissues. It is a condition where organs of the body breakdown, causing illness in the body. These diseases are caused when the normal functioning of the body is affected because of the inability of the organs to perform their functions or alteration in the cellular structures of the body over a period of time. Examples of these diseases are – Haemochromatosis, iron deficiency anaemia etc. Get to know more about diseases and related topics by registering at BYJU’S.

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