Class 9- Disease Diffusion Flashcards
1
Q
Disease Diffusion
A
- Disease diffusion
- A disease spreads through interactions among infected and susceptible hosts
- Understanding the geographical patterns is crucial to how and where diseases spread
- A disease spreads through interactions among infected and susceptible hosts
2
Q
Spatial diffusion
A
- Spatial diffusion is the movement of some phenomena through space and time
- e.g., people, goods, diseases
3
Q
Disease Diffusion: Space and Time
A
- Space and time
- Consider the fun that you just had putting together a spatial dataset!
- Now, multiply by time
- Common issues
- Changes in measurement (of disease or outcome)
- Changes in geographic scale (or in the case of Zip Codes, the units themselves)
- Consider the fun that you just had putting together a spatial dataset!
4
Q
Contagious Diffusion
A
- Disease spreads outward from point of origin
- Reflects local nature of human spatial interaction
- More interaction with those that live/work near a person
- Basic geographic movement
- Physical distance measures can be employed to understand movement from place to place
- Radial movement from source
- Very simple to understand because simple process governing
- Maybe a better model prior to modern transportation systems?
- Assumes a very unconnected world
- Human contact only occurs locally
- Reflects local nature of human spatial interaction
5
Q
Hierarchical Diffusion
A
- Disease jumps from place to place, based on population size
- Skips areas “between” places
- Actual distances may be large
- Begins in large population centers
- Moves from center to center
- Large populations, strong transportation connections, and movement
- Over time, moves from population centers to smaller cities, towns, villages
- Large populations, strong transportation connections, and movement
- Moves from center to center
6
Q
Network Diffusion
A
- Network diffusion is like Hierarchical diffusion
- Disease jumps from place to place
- Disease follows transportation or social networks
- Transportation: contact among regions may be restricted along specific routes
- Social: interaction and contact may be more related to “social” distances than physical distances
- Improvements/advances in modern transportation systems
- Traveling among regions (globally) is much easier than in the past
- A more modern approach to understanding disease diffusion?
- Traveling among regions (globally) is much easier than in the past
7
Q
Barriers to Disease Diffusion
A
- Barriers
- Slow or stop movement of a disease or people
- Physical features
- e.g., mountains, oceans
- Cultural/social
- Behavior
- Susceptible populations
- Immune groups of people
- Physical features
- Slow or stop movement of a disease or people
8
Q
Analyzing Diffusion: Mapping over time
A
- Mapping over time
- Disease rates at specific time intervals, based on past data
- Understand geographic component (diffusion) of the disease
- May assist in identifying transmission pathways
- Difference between incidence and prevalence!
- Disease rates at specific time intervals, based on past data
9
Q
Key factors when mapping over time: Predictive approach
A
- Identifying areas or populations having potentially elevated levels of risk
- Based on known factors and current disease distribution data
- Focus mitigation or intervention efforts
- Based on known factors and current disease distribution data
10
Q
Map sequence
A
Static maps, displayed in a sequence
11
Q
Animated maps
A
- Dynamic display
- Helps to understand change through visualization
- Very effective for displaying infectious disease diffusion
12
Q
Mapping Diffusion: Simulation models
A
Agent-based, spatially aware models
13
Q
Mapping Diffusion: Spatial interaction models
A
Gravity model
14
Q
Mapping Diffusion: Transforming space
A
Network diffusion
