Malaria

Question 1

Give evidence for malaria in Singapore

Answer 1

Approximately 100-300 cases per annum in Singapore and almost all are imported. 16.8% of cases in 2009 were reported locally which is an increase of 16.1% compared to 2008

Question 2

Give evidence for malaria cases in Africa

Answer 2

Africa is home to 95% of all malaria cases and 96% of deaths. Children under age of 5 accounted for 80% of all malaria deaths in the region. Four African countries accounted for over half of malaria deaths globally. Nigeria(31.9%), DRC(13.2%), Tanzania(4.1%) and Mozambique(3.8%)

Question 3

Describe antimalarial medications

Answer 3

Antimalarials are a type of antiparasitic chemical agent that can be used to treat of prevent malaria

Question 4

How do malaria parasites resist antimalarials

Answer 4

Malaria parasites have ability to develop resistance to antimalarials and is caused by incompletely treating an infected person, causing a handful of drug resistant pathogens to survive exposure to drug while drug sensitive pathogens die. Having nothing to stop them, drug-resistant pathogens can multiply

Question 5

What are reasons for incomplete treatment of malaria

Answer 5

Poverty - infected individuals cannot afford complete doses of the drug
Consuming cheaper counterfeit drugs
Inadequate healthcare facilities - unable to provide timely treatment

Question 6

Give evidence for rising resistance to anti-malaria drugs

Answer 6

2009, resistance to anti-malaria drugs observed along Thai-Cambodia border. Up to 80% of most common malaria parasites are resistant to two most common antimalarial drugs
Similar resistance to longtime frontline malaria drug, chloroquine contributed millions of deaths in Africa in 1980s

Question 7

How does population movement contribute to diffusion of infectious diseases

Answer 7

Movement of people across borders leads to relocation diffusion of infectious diseases. Malaria control programmes are ineffective as it is difficult to monitor movement of people. Better transport links between countries such as air travel contributed to increase in scale and speed of population movement

Question 8

Give an example of diffusion of malaria due to population movement

Answer 8

In 1995, malaria was reported in southern France which is non-endemic to malaria. People who were infected had not travelled nor received blood transfusions

Question 9

Why is it difficult to regulate population movement

Answer 9

There is uncontrolled migration and lack of border controls which greater spreads drug-resistant malaria. Travels advisories are useful in reducing travel to places where there is high risk of infection but may not be effective

Question 10

Give evidence for travel advisories helping reduce travels where risk of infection for malaria is high

Answer 10

Fitfortravel is public website providing up to date health information for UK public on avoiding illness and staying healthy when travelling abroad. However it may not reach those without access to news or illiterate people

Question 11

How does forest clearance promote breeding of mosquitoes

Answer 11

• rate of infiltration falls and allows water to accumulate on ground, forming pools of stagnant water for mosquitoes to breed
• water tends to be pH neutral, suitable for mosquito larvae
• loss of biodiversity, decrease in predators
• irrigation based intensive agriculture(wet rice farming)

Question 12

Give an example for deforestation leading to stagnant water for breeding

Answer 12

Extensive deforestation in the Brazilian Amazon to clear land for agriculture and cattle ranching lead to soil erosion and the creation of stagnant water bodies in the deforested areas. As stagnant water accumulates in these areas, they become prime breeding grounds for Anopheles mosquitoes, which are the primary vectors for malaria.

Question 13

How does climate change affect spread of malaria

Answer 13

Malaria endemic areas are tropical and sub-tropical regions. Climate affects temperature of area and amount of rainfall it receives, warm humid climatic conditions are favourable to mosquito breeding

Question 14

How does increased temperature and rainfall contribute to spread of malaria

Answer 14

Increased temperatures speed up rate at which mosquitoes breed and mature
Lengthened summers lengthen time period suitable for breeding of mosquitoes
Warmer temperatures allow mosquitoes to move to higher altitudes
Increased rainfall provides more pools of standing water for breeding of mosquitoes

Question 15

Give evidence for rainfall leading to increased malaria cases

Answer 15

From 1987-2007, India has seen a rise in malaria cases whenever rainfall increases from 100 millimeters to 300 millimeters

Question 16

Give evidence on Kenya where climate change led to spread of malaria

Answer 16

Climate change raised average temperatures in Central Highlands region of Kenya, allowing malaria to occur in areas of higher altitudes. This resulted in an additional 4 million people at risk of malaria.

Question 17

Give evidence on Ethiopian Highlands where climate change led to spread of malaria

Answer 17

Region of high-altitude plateaus and mountains above 14,000 feet have long provided topographic defence against spread of malaria. Temperatures have historically been too cold for Plasmodium parasites(mostly responsible for malaria in the region), but as global temperatures rise situation is changing

Question 18

Why dont people living in malaria endemic areas take more action against malaria

Answer 18

It is so common it has become part of their lives
May not be motivated to take actions
Measures like insecticide-treated bed nets are not popular due to discomfort sleeping within hot and humid climates

Question 19

Give an example of lack of action against Malaria

Answer 19

A child in Malawi might already have 12 episodes of malaria before he/she reaches the age of two

Question 20

Describe how overcrowded living conditions lead to spread of malaria

Answer 20

In situations where large number of people live together in small area the people interact with each other more closely and diseases spread quickly
Migrants overcrowded in living dormitories in LDCs, dwellings unhygienic and no proper door to keep out mosquitoes, easier for mosquitoes to go from person to person

Question 21

Sociodemographic impact of malaria

Answer 21

Increased death rate, increased infant mortality rate as infected mothers can pass on malaria and infect unborn child(70k to 200k die from malaria infections leading to low birth weight)

Question 22

Economic impacts of malaria

Answer 22

Increased burden on households, cost of healthcare(can account for up to 40% of public health spending on countries, must set aside funds) and loss of productivity (people infected may not be able to work due to poor health, loss of productivity for workforce and lower economic growth(Africa slowed up to 1.3% a year)