Health and Disease KQ2 and KQ3 (Malaria) Flashcards
What and how Malaria is transmitted?
- Life-threatening parasite induced disease
- Vector-borne via Anopheles female mosquito
1) Mosquito takes bloodmeal w/ malaria parasite
2) Parasite breeds in mosquito
3) Mosquito injects parasite into healthy person
4) Parasite infects person, moves to liver to reproduce and spread into bloodstream
Extent and spread of Malaria
- Spread via expansion diffusion
- Endemic in tropics and sub-tropics
- Can occur in non-endemic countries when infected person travels
Malaria in Africa
- 90% malaria deaths occur in Africa
- African mosquitoes have longer lifespan, prefer to feed on human blood than animal blood
- Higher incidence of malaria = higher mortality rates
Groups vulnerable to Malaria
1) 50% world population live in areas endemic to Malaria
2) Pregnant women and young children
3) Immuno-compromised individuals
Factors contributing to spread of Malaria
> Socio-economic
1) Lack of proper sanitation
2) Overcrowded living conditions
3) Limited provision and access to HC
> Environmental
1) Poor drainage and stagnant water
2) Effect of climate
SEF: Lack of proper sanitation
- Waste water not disposed of
- Forms stagnant water pools
- Favourable breeding ground for mosquitoes
- Increases risk of malaria spread when near housing and settlements
SEF: Overcrowded living conditions
- Large number of people clustered together in small area
- Share same spaces and use same items
- Interact with each other more often and closely = faster spread of diseases
- Overcrowded and unhygienic rooms w/o proper ventilation speeds up rate at which humans get bitten
- Nocturnal anopheles mosquitoes enter and spreads malaria
SEF: Limited provision and access to HC
> Limited HC
- Shortage of doctors, lack of health services and high costs of treatment increase spread of malaria
- Delayed treatment = increased time for spreading
- Caused by low investment in HC sector, govt funds concentrated elsewhere
e.g. India, highest number of malaria cases in Asia
- 6 doc per 10,000 patients
- 4% of GDP spent on HC
> Inaccessible treatment
- Artemisinin Combination Therapy (ACT) unaffordable in many poor places where malaria is prevalent
- Cannot afford = resort to cheaper/less effective treatments or no treatment at all
- Treatment over long term, financially draining
- Partial/incomplete course of treatment may cause malaria parasite to develop resistance to drug, requiring more expensive medication to treat
EnvF: Poor drainage and stagnant waters
- Creates favourable conditions for growth of mosquitoes
- Low awareness, no precautions, mosquitoes breed quickly w/o interruption
e.g. Rajasthan canals, India
- Parts of the 800km long canals leaked, developing swamps serving as breeding grounds for anopheles mosquitoes
- Frequent malaria outbreaks in north-western india
EnvF: Effects of climate
> Temp
1) 22-33*c increases lifespan of mosquito
- Increases frequency of bites
2) High temps shorten development time of parasites in mosquito host
- Mosquitoes become infectious sooner
3) High temps decrease aquatic life cycle from 20 days to 7 days
- Mosquitoes become active sooner
> Rainfall
1) Poor drainage and evaporation create stagnant pools of water, providing breeding grounds
2) Monsoon seasons bring large amounts of rainfall
- Wash away breeding grounds, temporary decrease in malaria cases
- Pools form from heavy rains, stagnate, breed mosquitoes, spike in malaria cases weeks after monsoon season ends
> Relative Humidity
1) Ranges from 50%-60% needed for survival of mosquito
- High humidity increases lifespan of mosquito
- Able to infect more people
Impacts of malaria
> Social
1) Death rate
2) IMR
> Economic
1) Household burden
2) Cost of HC
3) Loss of productivity
SI: Death rates
- 241 million cases of malaria in 2020
- 630, 000 deaths from malaria in 2020
- Africa was home to 95% of malaria cases and 96% of malaria deaths, 2020
- Children under 5 accounted for about 80% of all malaria deaths in Africa, 2020
SI: IMR
- Women who contract malaria during pregnancy may infect unborn child
- Around 75,000 to 200,000 infants die within first year of birth due to malarial infection during pregnancy
- May result in under-developed immune system
- Immunocompromised may die from basic diseases
EI: Household burden
- Increased medical expenses
e.g. Ghana, 34% of household income spent on HC
EI: Cost of HC
- Countries affected by malaria needs to set aside funds for building, maintaining and investing in medical infra, purchase of medicine, equipment (i.e. insecticide treated nets)
- e.g. Malaria accounts for 40% of public health spendings in some countries
