Health + Disease

• Communicable diseases:

  1. Infectious diseases
  2. Caused by pathogens (disease causing micro-organisms)
  3. Can be passed from one person to another
  4. Transmission can occur by: Direct contact, water, air, unhygienic food preparation, vectors (bugs/insects/animals)
  5. E.g: Aids, flu, chicken pox
• Non-Communicable diseases:

  1. Cannot be spread from one person to another
  2. Some are chronic
  3. Degenerative disease is a disease that causes breakdown in body cells, tissues and organs as it progresses
  4. Congenital disorders are all disorders are disorders that are present when the baby is born
  5. Heredity is the passing of traits from parents to their children
  6. e.g: cancer, deafness, arthiritis
• Chronic: Present either continuously or on and off over a long period
• Factors that can effect health: Diet, exercise, hygiene, age, conflict, pollution, weather
• Viruses living in cells can be triggers for cancers
• Defects in the immune system mean that an individual is more likely to suffer from infectious diseases
• Immune reactions initially caused by a pathogen can trigger allergies such as skin rashes and asthma
• Severe physical ill health can lead to depression / other mental illnesses
• Immunoglobulin: Chemicals released by cells
• Antihistamines: Drug given to combat the effect of Immunoglobulin
• Drugs are substances that cause changes to the body. Some drugs can help the body but other can harm it
• Creating a new drug:

  1. Research - can take years - tests for shelf life
  2. Testing - on cells/tissue cultures - tests for safety
  3. Small animals - may move to giving it to primates - tests for side effects
  4. Small group of healthy volunteers - tests for safety + side effects
  5. Small group of patients - tests for safety + efficacy - start to look at dosage
  6. Large group of patients - representative of population - tests for safety, efficacy and dosage
  7. Peer review - work gets checked
  8. FDA approval
  9. New drug
• Placebo: Fake drug, no medicine, but same in every other way
• Control group:

  Take the placebo

  We compare placebo with non-placebo
• Double blind test: Doctors and patients don't know who has the placebo
• Bias: We don't want this, it's one sided
• Randomisation:

  Who has the placebo vs medication

  Large sample = representative
• Epidemiology: The study of incidence (number of cases) of diseases and pattern of a disease with a view to finding the means of preventing or controlling it
• Risk factor: Will increase the likelihood or chances of an event occurring
• Correlation does not prove cause and effect, another factor may be involved
• Ionising radiation: High energy radiation that increases the chance of a mutation in DNA. Causes cells to divide uncontrollably. Leads to a tumour
• Risk factors can be:

  Aspects of a person's lifestyle

  Substances in the person's body or environment
• Benign cancer:

  • Doesn't spread
  • Slow growing
  • Capsulated (membrane around it)
  • Do not metastasize (spread through blood)
  • Dangerous based on location
• Malignant cancer

  • Will spread
  • Fast growing
  • Not capsulated
  • Metastasize
  • Dangerous because they can spread