Disease Diffusion Flashcards
(20 cards)
What causes the spread of disease?
Crowded living conditions
Unclean water
Low income
Inadequate education
What are the 4 main types of disease diffusion?
Expansion
Relocation
Contagious
Hierarchical
Describe expansion diffusion:
Disease has a source and spreads into new areas
Source area stays infected
(E.G. TB outbreak)
Describe relocation diffusion:
Disease leaves origin area
E.G. HIV
Describe contagious diffusion:
Spread occurs through direct contact with others
E.G. Ebola
Describe hierarchical diffusion:
Disease spreads from large urban areas to smaller ones (transport links etc..)
(E.G. SAARS)
Define disease diffusion:
Process by which disease spreads outwards beyond its geographical source
Who made the diffusion model that we looked at?
Hagerstrand
What shape was the Hagerstrand Diffusion Model?
S shaped curve
What are the (3) most important concepts of Hagerstrand’s Diffusion Model?
Neighbourhood Effect
S shape represents number of people infected
Physical barriers interrupt progress
What are the 4 stages of the Hagerstrand Diffusion Model?
Primary
Expansion
Condensation
Saturation
What is the Neighbourhood Effect?
People living in close proximity have a greater probability of contraction
Describe the primary stage of the Hagerstrand Diffusion Model:
Disease begins to grow and spread
Diffusion rate is slow bc few have the disease
Describe the expansion (diffusion) stage of the Hagerstrand Diffusion Model:
Rapid acceleration in disease diffusion (hierarchical diffusion)
Describe the condensation stage of the Hagerstrand Diffusion Model:
Most people have the disease -> spread is limited
Describe the saturation stage of the Hagerstrand Diffusion Model:
Disease diffusion rate slows right down
Disease incidences reaches its peak
What are some of the criticisms of the Hagerstrand Diffusion Model?
No eradication stage (stage 5)
No resurgence stage (e.g. measles due to anti-vac beliefs)
What are some of the physical barriers to disease?
Distance
Mountains
Oceans
Deserts
What are some of the human barriers to disease?
Political border checks
Quarantine
Education
Mass vaccination
What human factors hinder disease management?
Social stigma (HIV = Gay disease) Poor food/water source Poverty Cost of medicine Lack of education
