Immunology

• Bacterium


  • 0.5 µm – 5 µm
• Fungus


  5 µm – 50 µm
• Protist


  1 µm – 2 mm
• Virus


  20 nm – 350 nm
• What is a pathogen?

  A microorganism which are the causative agents of disease
• What are some examples of bacterial diseases?

  chlamydia, gonorrhoea, tuberculosis
• What are some examples of viral diseases?

  common cold, mumps and measles
• What are some examples of fungal diseases?

  Athlete's foot, ringworm, yeast infection (thrush)
• What is an example of a prion disease?

  Creutzfeldt-Jakob disease
• What is an example of a protist disease?


  Malaria
• What is an example of a parasite disease?

  toxoplasmosis
• What is direct transmission?

  Direct transmission refers to the spread of a disease or infection from one person to another through close contact or physical contact.

  • physical contact with an infected person or contaminated surface (for example skin-to-skin contact)
  • sharing of needles
  • unprotected sexual contact
  • airborne: pathogen is carried by dust or droplets in the air, can exist in the air for some time (for example inhaling infected droplets)
• What is indirect transmission?

  Transmission of a disease through an intermediate source, such as contaminated objects or vectors.

  • vehicle transmission (for example ingesting infected food or water (faecal-oral); blood from inanimate objects (for example bedding)
  • being bitten by an infected ‘vector’ (for example insect bites)
• How can diseases spread amongst populations and communities?

  • inadequate sanitation (for example lack of access to clean water and inadequate sewage disposal)

  • lack of social distancing due to dense population

  • lack of accessible health promotion information
• What is an antigen?


  A substance that is recognised by the immune system as self or non-self and stimulates an immune response
• What is an antibody?

  A blood protein produced in response to, and counteracting, a specific antigen
• What is the link between antigens and the initiation of the body's response to invasion by a foreign substance?

  • antigens as chemical markers found on the surface of cells

  • ability of the body to recognise self and non-self-antigens

  • recognition of non-self-antigen leading to the initiation of an immune response
• What is the role of non-specific defences?

  • use of physical and chemical barriers
  • inflammation
  • phagocytosis
• What is the role of specific defences?

  • actions of T-cells
  • actions of B-cells
• What is a cell-mediated response?

  A cell-mediated response is associated with T-lymphocytes destroying pathogens (causative agents) without producing antibodies
• What is an antibody-mediated response?

  An antibody-mediated response is associated with B-lymphocytes destroying pathogens (causative agents) by producing antibodies against it
• What is the role of T and B cells in the secondary immune response?

  • they trigger a stronger and more rapid immune response after encountering the same antigen

  • role of vaccinations in relation to T and B memory cells
• What is an injury?

  defined as damage to the body caused by external force
• How does the body react to an injury?

  • involuntary inflammatory response
  • proliferation phase
• What is trauma?


  It is defined as an injury that has the potential to cause disability or death
• How does the body respond to trauma?

  • involuntary inflammatory response
  • loss of organ function
  • bone structure deformity/damage/loss of structure
  • haemorrhaging
  • multi organ failure
  • ischemia
  • proliferation phase
• What is the role of an MRI?


  It uses strong magnetic fields and radio waves to generate detailed images of inside the body
• What are the considerations for use of an MRI?


  • patient medical history including medical implants containing magnetic metals
  • preparing the patient including the removal of all external metallic objects