Diseases

Question 1

What are infectious diseases

Answer 1

Spread by pathogens

Question 2

What are communicable diseases

Answer 2

Disease that can be passed from one person to another

Question 3

What are contagious diseases

Answer 3

Infectious disease that spread easily through direct contact

Question 4

What is non infectious disease

Answer 4

Non communicable, diseases that are not passed from person to person

Question 5

What are non contagious diseases

Answer 5

Diseases that are not spread through direct contact

Vector borne diseases

Question 6

What is endemic

Answer 6

An infectious disease that permanently exists in a geographical area
Seasonal flu in UK

Question 7

What is epidemic

Answer 7

Disease outbreak attacking many people at the same time in a restricted area
Monkey pox

Question 8

What is pandemic

Answer 8

When epidemic is spread worldwide
Need to reach certain amount of threat
Black Death/ Covid19

Question 9

Global distribution of malaria

Answer 9

High concentration in Africa- 95% of malaria deaths

Question 10

Global distribution of HIV

Answer 10

Spread through exchange in body fluids
36 million infected worldwide in 2015
Greatest burden in Sub Saharan Africa (70% of global)

Question 11

Global Distribution of tuberculosis

Answer 11

Airborne
1.8 million deaths form tuberculosis in 2015
South east Asia accounts for 45% of the cases
95% of the deaths are from LIDCs and EDCs

Question 12

Global Distribution of non communicable diseases (Diabetes and CVDs)

Answer 12

Diabetes: 422 million live with diabetes
Prevalence: Saudi Arabia 22%, US 10%, UK 4.7%

CVDs: number one cause of deaths, 31% of all deaths
82% in LIDCs and EDCs

Question 13

What is the world’s main cause of death

Answer 13

Heart disease and stroke
32% of global deaths

Question 14

What is burden of disease

Answer 14

The number of disease that a country needs to deal with

Question 15

What are diseases of affluence

Answer 15

Non communicable diseases
They are more prevalent in ACs than LIDCs as there is higher ageing population

Question 16

Global Distribution of Diabetes

Answer 16

Non communicable
Highest concentration in Asia and North America

Question 17

Global Distribution of cardiovascular disease

Answer 17

Non communicable disease
Major cause of death in ageing population in ACs
High rates in Africa and Russia

Question 18

What are disease of poverty

Answer 18

Infectious diseases linked to poor sanitation, low vaccination coverage, and limited services
Mainly in LIDCs
HIV/AIDs, cholera, tuberculosis
98% of tuberculosis deaths are in LIDCs

It is changing as global development shifts through the ETM

Question 19

What are criticisms of disease of affluence and poverty

Answer 19

Too binary
Most deaths of Non communicable diseases are in LIDCs
Although prevalent in ACs, but much less compared to LIDCs

Communicable diseases such as COVID had influenced worldwide

Question 20

What is does countries like India suffers

Answer 20

Double Burden of disease
As they are ‘transitioning country’

Question 21

What is disease diffusion

Answer 21

The spread of disease from its source into new areas

Question 22

What is distance decay

Answer 22

‘Neighbourhood effect’

The incidence (number of new cases) of disease is affected by distance

Places closer to the source are more likely to see a higher incidence of disease

However, in a globalised world, the increasing connection through transport and migration cause disease to spread faster

Question 23

What ar the 4 types of disease diffusion

Answer 23

Relocation diffusion

Expansion diffusion

Contagious diffusion

Hierarchical diffusion

Question 24

Explain expansion diffusion

Answer 24

Occurs when a disease spreads outwards from the source into new areas

Spanish Flu in 1918- killed 40 million people worldwide

Question 25

Explain contagious diffusion

Answer 25

Spread of infectious disease through direct contact of individuals with those infected

Question 26

Explain relocation diffusion

Answer 26

Spreading disease moving into new areas leaving behind the source of disease E.g cholera in Haiti- brought by aid workers coming from Nepal Leap from one location to another

Question 27

Explain hierarchical diffusion

Answer 27

Spread of disease through an ordered sequence of classes or places From urban areas to rural areas COVID-19

Question 28

Physical barriers to disease diffusion

Answer 28

Distance- distance decay Physical features- mountains, oceans, deserts, remoteness Climatic- extreme climates deter the spread, Malaria only transmit between 18-40C

Question 29

Human barriers to disease diffusion

Answer 29

Mass Vaccination programme Quarantine Travel restrictions and migration controls Social distancing Education and public health- increased awareness Behavioural- wearing masks

Question 30

Explain the Hagerstrand’s diffusion model

Answer 30

Neighborhood effect- built on top of distance decay theory- populations living in close proximity has greater probability of contracting the disease 1: initial development of infection with low total number and diffuse slow due to no symptoms shown yet 2: exponential growth as disease spread through population 3: eventually plateaus as the population are all infected or had found mitigation strategies

Question 31

Evaluation of Hagerstrand’s Model

Answer 31

Too simplistic Globalised world- disease spread faster and more randomly

Question 32

Temperature and precipitation linked to prevalence of disease

Answer 32

Malaria/yellow fever/dengue fever- require warm and humid conditions They are endemic in tropical areas as they can’t develop in higher latitude areas which have lower temperature Precipitation creates aquatic habitats- stagnant pools of water allowing vectors to breed and flourish E.g anophelines mosquitos breed in water- malaria transmission highest in rainy season

Question 33

Seasonality linked to prevalence of disease

Answer 33

Vectors like mosquitoes only live in certain climate conditions Peak of transmissions are after rainy seasons or monsoon seasons

Question 34

Relief linked to prevalence of disease

Answer 34

Linked to temperature Every 100m gain in elevation, temperature drops by 1C- malaria

Question 35

Climate change increasing spread of disease

Answer 35

Vector borne diseases may spread into higher altitude and latitude areas With higher temperature, mosquitoes can mature faster and can spread faster- Malaria and Dengue Fever (spread into US and Europe) Rising sea temperature- increase cholera Increase extreme weather events such as hurricanes and heavy rainfall can contaminate drinking water and crops and displacement of people Increase transmission seasons However if temperature become too high, the mosquitoes can’t survive Drought- crop failure Extreme rainfall can damage crops- food shortages Wildfires- releasing smoke and pollutants- respiratory issues Climate change is expected to cause about 250,000 more deaths per year from malnutrition, malaria, heat stroke Extreme high air temperature could contribute to cardiovascular and respiratory disease Heat wave in 2003, 70,000 excess deaths in Europe

Question 36

Conditions for zoonotic disease to establish and spread

Answer 36

Unrestricted movement of infected wild animals by physical barriers Ineffective control of movement of infected domestic animals Urbanisation creating habitats to foxes, raccoons, Low prevalence of vaccination of pets Poor sanitation and contamination of water by faeces