Theory

Created by

Mabel smith

Cards (28)

What does infectious mean
Disease caused by a pathogen
What does contagious mean
Spreads from person to person
What does communicable mean
Spreads from host to host
What does zoonotic mean
Spreads from animal to person
What is an epidemic
A disease outbreak that attacks many people at the same time in one area
What is an endemic
Exists permanently in a specific area
What is a pandemic
An epidemic that spread globally like Covid
What is disease diffusion
Process by which a particular disease spreads outwards from its source
What is expansion diffusion
Where the disease spreads outwards into new areas when the main source remains infected
What is relocation diffusion
When a disease leaves area of origin and infects a new place
What is contagious diffusion  
When it passes person to person and spreads via direct contact
What is hierarchical diffusion
Spreads in an ordered sequence of places
What is hagerstrands diffusion model
A graph based on three concepts that shows 4 steps on how diseases diffuse
What are the three concepts of hargerstrands diffusion model
Neighbourhood effect
S shaped model
physical barriers
What is the neighbourhood effect 
When people live close to eachother the disease may spread faster
What are the four steps in hargerstrands model  
Primary step - strong contrast in disease incidence
expansion step - diffusion occurs and there are new outbreaks
condensation step - number of cases equals out
saturation step - diffusion decelerates as the incidence reaches its peak
What are some physical barriers to disease diffusion  
Distance
mountains
oceans
climate
desert
What are socioeconomic barriers to disease diffusion
Political borders
curfews
quarantines
masks
vaccinations
What are criticisms of hagerstrands model
Globalisation has meant diseases can spread much faster
eradication isn’t taken into account
What is a vector
Living organisms that can transmit infectious diseases between humans or from animals to humans
How is malaria spread
Female mosquitoes carry the parasite
Why is malaria mostly found in lidcs
Low health care
How does rainfall affect the prevalence of malaria
Prevalent in areas with over 1000mm of rain. Eggs are laid in stagnant water
How does temperature affect prevalence of malaria
More eggs are laid in higher temperatures and the larvae develop faster.
How does poverty affect prevalence of malaria
When people live in slums stagnant water and rubbish dumps becomes breeding grounds
how does climate change influence diseases like malaria
As climate increases the mosquitos will be able to survive in new places so there may be more cases.
A one degree rise in temp could lead to how many new cases  
3 million
Give an example of a disease caused by climate change
Anthrax - was frozen but after the thawing of the permafrost it spread from reindeer to humans and 2300 reindeer died