HIGHER / INTERMEDIATE GEOGRAPHY DEVELOPMENT AND HEALTH MALARIA.

HIGHER / INTERMEDIATE GEOGRAPHY DEVELOPMENT AND HEALTH

HIGHER / INTERMEDIATE GEOGRAPHY DEVELOPMENT AND HEALTH

MALARIAMALARIA

Choices …to run through the whole show, simply left-click your mouse button. To jump to a particular section, click on the appropriate button below. To return to this page, click

Choices …to run through the whole show, simply left-click your mouse button. To jump to a particular section, click on the appropriate button below. To return to this page, click

1. THE CAUSE1. THE CAUSE

2. THE EFFECTS2. THE EFFECTS

3. THE RISK FACTORS3. THE RISK FACTORS

4. THE SOLUTIONS4. THE SOLUTIONS

5. KEY REVISION POINTS5. KEY REVISION POINTS

MALARIA TODAY…MALARIA TODAY…

• Global population at risk - 2.3 billion people - about 40% of the world’s population

• Number infected - 500 - 600 million people

• Global annual mortality - 1.5 - 3 million deaths, or between 4000 and 8000 each day

• In the time it takes to say the word malaria, ten people, seven of them children, will have caught it.

• Every 30 seconds, a child dies of malaria.

After dropping steeply between 1930 and 1970, malaria is now making a real comeback, especially in Africa, south of the Sahara, where 90% of all deaths occur.

BackgroundBackground

The name comes from the Italian mal (bad) and aria (air) – it was originally thought the disease was spread by the damp air from swamps.

The name comes from the Italian mal (bad) and aria (air) – it was originally thought the disease was spread by the damp air from swamps.

The link between the disease and the Anopheles Mosquito was first made by Ronald Ross, a Scottish army doctor, working in India.

The link between the disease and the Anopheles Mosquito was first made by Ronald Ross, a Scottish army doctor, working in India.

Malaria is a disease which is endemic in many countries – this

means it is always present.

Malaria is a disease which is endemic in many countries – this

means it is always present.

It is predominantly a disease of the Tropics.

…with global warming, however, malaria may be closer than you think…

Sudden onset of cold stage – patient shivers violently and turns blue with cold, even though his actual temperature is rising. Lasts about

one hour…

Hot stage – high temperature,

headache, sickness and

dizziness. Lasts several hours…

Sweating stage patient soaked in sweat, but begins to feel

better after 2-3 hours…

Several days of

weakness and slow recovery

INFECTION

Several days of headaches and vague,

flu-like pains of the body…

THE COSTSTHE COSTS

• The huge cost in terms of human suffering: 1 – 3 million deaths a year. Hundreds of millions ill.

• Massive impact on attendance of children at school. Education suffers.

• Large numbers unable to farm their land or collect in the harvest. The harvest coincides with the peak biting season for mosquitoes.

THE COSTSTHE COSTS

• Enormous financial cost to families to buy anti malarial medicines. In some cases 25% of their annual income. This is on top of paying preventative costs and lost income.

• Over $2 billion dollars spent on fighting the disease in Africa alone, money which could be spent on development.

• Africa’s GDP would be $100 billion greater if malaria had been wiped out thirty five years ago.

• Tourists and foreign investors avoid malaria ridden areas.

Back to CHOICES

MALARIA - RISK FACTORS - 1ENVIRONMENTAL

• The presence of Anopheles mosquitoes• The presence of the plasmodium, in either

the mosquitoes or human population.• A warm, humid climate - temperatures

between 16°C and 40°C and abundant rainfall.

• Areas of still / standing water. Only a tiny area of water is needed.

• Vegetation nearby to provide shade for the mosquito to hide during the day and digest the blood meal from the night before.

MALARIA RISK FACTORS - 2

HUMAN

• Poor water supply and sanitation.• People nearby to provide reservoir of blood.• People working in the fields and in irrigation

systems, near or on lakes and reservoirs etc.• Migrants moving into malarial areas -

clearing land, looking for work, refugees etc.• People (and mosquitoes!) travelling abroad,

especially by air; airport malaria.

Collecting water, an

essential fact of life for millions

of people, poses real risks of

being bitten.

However, you cannot catch

the disease by drinking water

containing larvae.

3 Areas of Control3 Areas of Control

• Against the adult mosquito;

• Against the eggs and larvae;

• Against the Plasmodium, by treating victims.

1. AGAINST ADULT MOSQUITOES

1. AGAINST ADULT MOSQUITOES

INSECTICIDE TREATED BED

NETS(VERY SUCCESSFUL)

INSECTICIDE TREATED BED

NETS(VERY SUCCESSFUL)

GENETIC ENGINEERING

(VERY LIMITED SUCCESS)

GENETIC ENGINEERING

(VERY LIMITED SUCCESS)

DDTDDT

MALATHIONMALATHION

STERILE MALES

STERILE MALES

KILLER MALESKILLER MALES

INSECTICIDE SPRAYS

(SUCCESSFUL…BUT)

INSECTICIDE SPRAYS

(SUCCESSFUL…BUT)

Insecticide sprays are very efficient, but there are several drawbacks:

1. They are relatively expensive, often beyond the means of poor villages;

2. Sprays must be applied repeatedly for long-term effectiveness.;

3. They may contaminate water and crops.

Insecticide sprays are very efficient, but there are several drawbacks:

1. They are relatively expensive, often beyond the means of poor villages;

2. Sprays must be applied repeatedly for long-term effectiveness.;

3. They may contaminate water and crops.

4. Most importantly, mosquitoes can quickly develop immunity to the spray.

4. Most importantly, mosquitoes can quickly develop immunity to the spray.

The effect of stopping the use of DDT in Sri Lanka (Ceylon). Was the banning of DDT one of the costliest mistakes of all time? One estimate suggests that 50 million children have died of malaria since the use of

DDT was greatly reduced in the 1960s.

A simple mosquito net may mean the difference between life and death…

…even better if they are dipped in insecticide, as in this Kenyan village. The normal chemical

used for ITNs (Insecticide Treated Nets) is

Permethrin, which is harmless to humans, but

deadly to mosquitoes. Several African countries

are trying to get more people to use these nets, by removing tax on them,

reducing their cost.

…even better if they are dipped in insecticide, as in this Kenyan village. The normal chemical

used for ITNs (Insecticide Treated Nets) is

Permethrin, which is harmless to humans, but

deadly to mosquitoes. Several African countries

are trying to get more people to use these nets, by removing tax on them,

reducing their cost.

2. AGAINST EGGS AND LARVAE2. AGAINST EGGS AND LARVAE

PHYSICALPHYSICAL

CHEMICALCHEMICAL BIOLOGICALBIOLOGICAL

DRAINING BREEDING

SITES

DRAINING BREEDING

SITES

FLUSHING BREEDING

SITES

FLUSHING BREEDING

SITES

PLANTING EUCALYPTUS

TREES

PLANTING EUCALYPTUS

TREES

SPRAYING WITH

LARVICIDES

SPRAYING WITH

LARVICIDES

ADDING OIL, EGG WHITES OR

MUSTARD SEEDS

ADDING OIL, EGG WHITES OR

MUSTARD SEEDS

ADDING FISH TO PONDS AND PADI

FIELDS

ADDING FISH TO PONDS AND PADI

FIELDS

ADDING Bti IN

COCONUTS

ADDING Bti IN

COCONUTS

PHYSICAL CONTROLPHYSICAL CONTROL

Draining breeding places: because mosquitoes need so little water in which to lay their eggs, it can be virtually impossible to find and drain them all.

Draining breeding places: because mosquitoes need so little water in which to lay their eggs, it can be virtually impossible to find and drain them all.

Flushing out breeding sites by weekly release of water can drown the larvae, but can only be done in

suitable areas and where there is surplus water.

Flushing out breeding sites by weekly release of water can drown the larvae, but can only be done in

suitable areas and where there is surplus water.Planting Eucalyptus trees to absorb

excess water from the soil helps drain breeding sites.

Planting Eucalyptus trees to absorb excess water from the soil helps drain

breeding sites.

BIOLOGICAL CONTROLBIOLOGICAL CONTROL

Adding larvae-eating fish, such as the Muddy Loach, to padi fields and pools, can clear them of larvae within a day.

Adding larvae-eating fish, such as the Muddy Loach, to padi fields and pools, can clear them of larvae within a day.

BIOLOGICAL CONTROL - BtiBIOLOGICAL CONTROL - Bti

The bacillus Bti (Bacillus Thuringiensis Israelensis !!!) can be incubated in coconuts, where it multiplies. The coconuts are then broken open and thrown into pools, where the bacilli are eaten by the mosquito larvae.

They kill the larvae by destroying its gut.

The bacillus Bti (Bacillus Thuringiensis Israelensis !!!) can be incubated in coconuts, where it multiplies. The coconuts are then broken open and thrown into pools, where the bacilli are eaten by the mosquito larvae.

They kill the larvae by destroying its gut.

Spraying Bti from a boat

Spraying Bti from a boat

The incubation

stage

The incubation

stage

Adding to

pools

Adding to

pools

BIOLOGICAL CONTROL - BtiBIOLOGICAL CONTROL - Bti

You can even buy Bti over

the counter in the U.S.

You can even buy Bti over

the counter in the U.S.

3. AGAINST THE PLASMODIUM…3. AGAINST THE PLASMODIUM…

An ingredient of Tonic Water (check in the supermarket), Quinine was often

taken with Gin to mask its bitter taste. However, you would need to drink about

25 Gin and Tonics a day to get the recommended dose.

An ingredient of Tonic Water (check in the supermarket), Quinine was often

taken with Gin to mask its bitter taste. However, you would need to drink about

25 Gin and Tonics a day to get the recommended dose.1. Quinine:

Originally extracted from the bark of the South American Cinchona (Fever Tree), it was for a long time the

main anti malarial drug.

1. Quinine: Originally

extracted from the bark of the South American Cinchona (Fever Tree), it was for a long time the

main anti malarial drug.

AGAINST THE PLASMODIUM…AGAINST THE PLASMODIUM…

2. Chloroquine: Now the most common anti malarial drug, but, like Quinine, becoming ineffective as the Plasmodium mutates and becomes immune to it.

2. Chloroquine: Now the most common anti malarial drug, but, like Quinine, becoming ineffective as the Plasmodium mutates and becomes immune to it.

..AGAINST THE PLASMODIUM..AGAINST THE PLASMODIUM

3. Artemisia (Wormwood): Used as an anti malarial herbal remedy by the Chinese for hundreds of years (known there as Qinghaoshu), it was “rediscovered” during the Vietnam war and may prove to be a major weapon in the fight against malaria, as plasmodium do not seem to become immune to it.

3. Artemisia (Wormwood): Used as an anti malarial herbal remedy by the Chinese for hundreds of years (known there as Qinghaoshu), it was “rediscovered” during the Vietnam war and may prove to be a major weapon in the fight against malaria, as plasmodium do not seem to become immune to it.

VACCINATIONVACCINATION

At the moment, there is no effective vaccine against malaria, although

scientists all over the world are trying to develop one.

At the moment, there is no effective vaccine against malaria, although

scientists all over the world are trying to develop one.

The search goes on to try

to find a vaccine: the Bill

Gates Foundation

recently donated more

than $168 million towards

malaria research, most of that to find an effective

vaccine available to all.

The search goes on to try

to find a vaccine: the Bill

Gates Foundation

recently donated more

than $168 million towards

malaria research, most of that to find an effective

vaccine available to all.

ROLL BACK MALARIAROLL BACK MALARIA

Started in 1998, Roll Back Malaria is a global programme aimed at halving the world's malaria problem by 2010.

It is a coordinated attempt involving the WHO, UNICEF, the World Bank and many governments and scientific and medical experts across the world.

Started in 1998, Roll Back Malaria is a global programme aimed at halving the world's malaria problem by 2010.

It is a coordinated attempt involving the WHO, UNICEF, the World Bank and many governments and scientific and medical experts across the world.

SUCCESS OR FAILURE?SUCCESS OR FAILURE?

• At the moment there is no doubt that the battle against malaria is being lost.

• This is mainly due to the ability of mosquitoes to develop immunity to pesticide sprays…

• …and to the Plasmodium’s ability to develop resistance to drugs.

• At the moment there is no doubt that the battle against malaria is being lost.

• This is mainly due to the ability of mosquitoes to develop immunity to pesticide sprays…

• …and to the Plasmodium’s ability to develop resistance to drugs.

5. KEY REVISION POINTS5. KEY REVISION POINTS

• Anopheles Mosquito;• Plasmodium (e.g. Plasmodium

Falciparum);• Humid climate; 16-40ºC, abundant rainfall;• Vegetation for shade;• Areas of still or stagnant water;• Humans to act as blood reservoir.

• Anopheles Mosquito;• Plasmodium (e.g. Plasmodium

Falciparum);• Humid climate; 16-40ºC, abundant rainfall;• Vegetation for shade;• Areas of still or stagnant water;• Humans to act as blood reservoir.

(i) – THE PROBLEM(i) – THE PROBLEM

5. KEY REVISION POINTS5. KEY REVISION POINTS

• 1-3 million deaths each year, mostly children;• Lost education through bouts of illness;• Lost productivity by adults, especially at planting and

harvest time – less food, lower income;• Huge amount spent on trying to prevent or control malaria

- $2 Billion in Africa each year, maybe $100 Billion damage to Africa’s GDP; up to 25% of family income; huge burden on health services;

• Negative impact on foreign investment and tourism.

• 1-3 million deaths each year, mostly children;• Lost education through bouts of illness;• Lost productivity by adults, especially at planting and

harvest time – less food, lower income;• Huge amount spent on trying to prevent or control malaria

- $2 Billion in Africa each year, maybe $100 Billion damage to Africa’s GDP; up to 25% of family income; huge burden on health services;

• Negative impact on foreign investment and tourism.

(ii) THE EFFECTS (ii) THE EFFECTS

Exam AdviceExam Advice

• Practice this topic using past papers – the questions don’t vary that much from year to year.

• Concentrate more on the Risk Factors, Costs and the Solutions, less on the cycle of infection and medical symptoms of the disease.

• You must be able to comment on the effectiveness of your chosen solutions, but don’t just say “very effective” for them all and hope to get marks – the markers will be looking for detailed knowledge of the effectiveness of each solution you quote.

• Try to learn a few (four or five) solutions in detail and be able to quote names of pesticides, drugs, etc.

• Practice this topic using past papers – the questions don’t vary that much from year to year.

• Concentrate more on the Risk Factors, Costs and the Solutions, less on the cycle of infection and medical symptoms of the disease.

• You must be able to comment on the effectiveness of your chosen solutions, but don’t just say “very effective” for them all and hope to get marks – the markers will be looking for detailed knowledge of the effectiveness of each solution you quote.

• Try to learn a few (four or five) solutions in detail and be able to quote names of pesticides, drugs, etc.

Exam Question

• Q1) Malaria or cholera are common diseases in developing countries. Choose one of the diseases and answer the following questions.

• i) Describe how the disease is spread.ii) Describe the methods used to control the disease. Make reference to international organisations and aid agencies

Model Answer

• i) The female mosquito transmits malaria. The mosquito feeds on human blood and while doing this it transmits the malaria disease to the human host by the parasite, Plasmodium, which is present in the infected mosquito’s saliva. The mosquito’s saliva prevents the blood from clotting so as it can enjoy a blood meal. The mosquito only breeds in hot climates where there is stagnant water, sheltered vegetation and a source of blood to feed on, human or animal. As such malaria is widespread in Africa, Asia and South America.

• ii) There are several ways of controlling the disease. Insecticides can be used to kill the mosquitoes, stagnant water can be drained and protective clothing and mosquito nets can be used to prevent mosquito bites. Drugs can be used on people infected by malaria to combat its effects. An example of an anti-malaria project would be in Zambia where the W.H.O./UNICEF’s Rollback Malaria project has provided insecticide-treated mosquito nets to help cut down the number of malaria-related deaths.

Presentation produced by Robbie Livingstone, Geography Department, Dunoon Grammar School.

Photographs and diagrams are used without their authors’ permission and should not be used for any commercial purposes.

Any constructive criticisms are welcome – to [email protected]

…this presentation will have taken about half an hour to view. In that time about 60 people, most of them babies and young children will have died from malaria…