Download Factors that contribute to spreading of the disease

Malaria control
Factors that contribute to spreading of the disease
Human
 Humans – migration of people can lead to the spread of malaria
between regions.
 Stagnant water wells are a breeding ground for mosquitoes which
spread malaria
 Irrigation channels – An increase in the number of irrigation projects
has increased the risk of malaria as it provides even more breeding
grounds for mosquitoes.
 Water barrels – Provide breeding ground for mosquitoes.
 Padi-fields - These are areas of stagnant water ideal for mosquitoes to
breed in. they are also where people grow rice which is sold to make
their living. Many people work in this area, therefore have increased
contact with mosquitoes.
Environmental
 Climate – warm climates with temperatures over 15C provides
suitable breeding ground for anopheles mosquito.
 Mosquitoes like shaded areas as it is ideal for digesting human blood.
Strategies to control malaria
There are a number of ways in which to control malaria.
Insecticides
In Southern Africa most people are infected between January and april and
many people are infected while sleeping in their houses. Therefore residual
house spraying has been introduced.
Houses are sprayed before the season of greatest infection so that
mosquitoes will get a does of insecticide when they land on ceilings or walls.
This prevents malaria from being spread.
Anti-malarial drugs
If people become infected with malaria then treatment with anti-malarial drugs
will stop infection within that person and also reduce the risk of that person
infecting a mosquito and contributing to the cycle of infection.
Reducing breeding sites
If mosquitoes have fewer numbers of breeding grounds then there will be less
mosquitoes to spread the disease. Breeding grounds can be reduced using
the following methods:
 Draining areas that could be used for breeding grounds.
 It is also possible to plant eucalyptus plants, which soak up excess
moisture from the ground.
Killing larvae
If you kill mosquito larvae then you reduce the amount of mosquitoes
available to spread the disease. Larvae can be killed in the following ways:




Small fish introduced in to padi-fields to eat larvae
Mustard seeds in padi-fields drag the larvae below the surface and
they drown.
Egg whites can be sprayed on stagnant surfaces to suffocate the
larvae.
Flushing streams by damning and then releasing the water, and
drowning larvae.
Education
Campaigns to educate people about the disease and how to prevent it,
increase local awareness of the disease and shows people how to minimise
risk.
Problems with controlling malaria
Insecticide resistance
insecticides.
- mosquitoes have become resistant to certain
Drug resistance - certain strains of malaria have developed resistance to
drugs. Other drugs are being developed. The use of combination therapy
(more than one type of drug) is thought to reduce the risk of immunity if used
correctly. Chinese researchers extracted a fast-acting, anti-malaria agent
named artemisinin from a traditional Chinese herb in the 1970s. Tablets
based on this compound have been produced.
Migration – Movement of people to different regions has led to re -infection in
to areas cleared of malaria.
Irrigation schemes – These are important to increasing agricultural output so
more have been built, however this conflicts with reducing malaria.
Many people still suffer from malaria and the world health organisation has
now accepted that malaria will not be eradicated but aims to reduce the
disease.
Impact of malaria on a region
Malaria can create a huge economic burden for a country. This is due to the
number of hospital admissions and the cost of national malaria control
programmes.
Malaria can also have economic implications for individuals due to the cost of
anti-malarial drugs, treatment and loss of wages due to illness. Many malaria
suffers cannot afford and have no access to medical treatment.
Malaria can also limit foreign investment and tourism, which will have a
serious economic impact on the country’s development.
Malaria infection is highest during the rainy harvest season, when the workers
are needed; this can impact upon agricultural production.
Questions
Answer the following questions in sentences.
1)
2)
3)
4)
5)
What are the main human causes for spreading malaria?
What are the main environmental causes for spreading malaria?
How can insecticides control spread of malaria?
What is the problem with malaria?
Anti malarial drugs stop the spread of malaria what is the problem with
them?
6) Why does reducing breeding sites reduce malaria?
7) In what ways can we reduce the breeding sites?
8) How do we kill mosquito larvae?
9) Why is education important in reducing malaria?
10) What problems are there in reducing malaria?
11) Why might reducing malaria be good for a country?