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What is a disease?

A disease is a disorder in the function or structure of a part of the body that causes specific signs and symptoms. Additionally, these signs and symptoms do not directly result from physical injury.

There are four main types of diseases:

  1. Deficiency diseases (e.g., scurvy, hypocalcemia, iron deficiency)
  2. Infectious diseases (e.g., flu, strep throat, measles, salmonella)
  3. Physiological diseases (e.g., diabetes, asthma, glaucoma)
  4. Hereditary diseases (e.g., cystic fibrosis, hemophilia, sickle cell disease, muscular dystrophy)

Disease can affect various body regions or organs. Diseases can also vary based on how harmful they are to the individual or in what way they impact the person with the disease.

How do diseases affect healthcare?

Diseases negatively affect someone’s health due to their disruption of normal function or structure. Because of this, diseases make up a significant portion of healthcare regarding providing care and, depending on the disease, a cure.

Chronic diseases can significantly affect healthcare since they use more resources and can cause poorer health statuses.