Key Info

Question 1

what are the different types of disease diffusion

Answer 1

• Expansion diffusion – disease spreads outwards into new areas, meanwhile carriers in source area remain infected e.g. TB
• Relocation diffusion – disease moves into new areas spatially separate from the source e.g. from one continent to another
• Contagious diffusion – disease spreads through direct contact with a carrier e.g. ebola
• Hierarchical diffusion – disease spreads through from largest well connected locations to more isolated and smaller centres (can also be seen along transport networks)
• Hägerstrand’s probabilistic diffusion model -
  neighbourhood effect and S-shaped curve

Question 2

what are some disease risks

Answer 2

physical - stagnant water and temperature

human - development, social norms including diet and population density

Question 3

what is the epidemiological model and what does it suggest

Answer 3

that as countries become more wealthy the death toll shifts from communicable to non communicable disease