disease dilemmas Flashcards
infectious
- contagious
- non contagious
- communicable
- zootonic
non-infectious
- lifestyle causes
- environmental diseases
- nutritional causes
- genetic causes
contagious
Diseases which are easily spread between direct or indirect contact between people.
could be viral (eg ebola) or bacterial (eg plague)
non-contagious
Pathogens are spread by disease vectors e.g. mosquitoes and not by people.
communicable
Infectious disease which spreads easily from house to house but do not require quarantine.(HIV, herpes)
zoonotic
transmitted from animals to humans (rabies, plague, covid)
lifestyle causes
Disease is caused by lifestyle choices in habits (e.g. lung cancer diabetes)
environmental diseases
Disease is caused by exposure to toxins in the air water land food or the Sun e.g. skin cancer.
nutritional causes
Disease is caused by deficiency in particular macro or micro nutrients (diabetes, scurvy, rickets)
genetic causes
diseases caused by genetic inheritance (arthritis cancer) .
endemic
Usual prevalence of a disease within a population or geographical area
epidemic
An outbreak of a disease to infect many people at the same time and spreads to a population in a restricted geographical area
- not usual disease
Pandemic
And epidemic that has spread worldwide affecting a large number of people
Hagerstrand model of diffusion of diseases
four main types of diffusion
- expansion
- relocation
- hierarchical
- contagious
Expansion
Single source it spreads outwards from
disease intensifies in source area
Relocation
Delete these leaves an area and moves to new ones
people moving and bringing the disease there through travel.
Hierachincal
Spreads through ordered sequence of classes and places from
larger area to less populated area
Contagious
Disease spread through direct contact with a carrier
strongly influenced by difference
Hagerstrand “neighbourhood effect” in diffusion
The probability of contact between one carrier and a non-carrier is determined by the number of people living in each 5 x 5 km grid
closer together the more spread further the less spread
Hagerstrand 4 stages of diffusion
- Slow beginning not infected many people
- Number of infected accelerates rapidly
- Levelling out as susceptible people have been infected
- Fewer house virus starts to die off
- Heard immunity or Michigan techniques
Barriers to diffusion
physical and socio-economic
physical barriers
Ability for vectors to survive distance decay (people living far away not likely to interact so no spread of the disease)
climate
physical barriers e.g. mountain
socio-economic barriers
Amount of money for health care cultural factors
political border
management of disease.
