When the Anopheles Mosquito “bites”, it actually sinks a long, thin mouth part, the proboscis, into the skin. The mosquito then pumps saliva under the skin, to stop the blood clotting – so that it can drink uninterrupted! In the saliva is the main culprit, the Plasmodium , a single-cell blood parasite.
<ul><li>Insecticide sprays are very efficient, but there are several drawbacks: </li></ul><ul><li>They are relatively expensive, often beyond the means of poor villages; </li></ul><ul><li>Sprays must be applied repeatedly for long-term effectiveness.; </li></ul><ul><li>They may contaminate water and crops. </li></ul>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.
2. AGAINST EGGS AND LARVAE PHYSICAL CHEMICAL BIOLOGICAL DRAINING BREEDING SITES FLUSHING BREEDING SITES PLANTING EUCALYPTUS TREES SPRAYING WITH LARVICIDES ADDING OIL, EGG WHITES OR MUSTARD SEEDS ADDING FISH TO PONDS AND PADI FIELDS ADDING Bti IN COCONUTS
PHYSICAL 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. 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.
BIOLOGICAL CONTROL Adding larvae-eating fish, such as the Muddy Loach , to padi fields and pools, can clear them of larvae within a day.
BIOLOGICAL 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. Spraying Bti from a boat The incubation stage Adding to pools
BIOLOGICAL CONTROL - Bti You can even buy Bti over the counter in the U.S.
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. <ul><li>Quinine : Originally extracted from the bark of the South American Cinchona ( Fever Tree) , it was for a long time the main anti malarial drug. </li></ul>
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.
..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.
VACCINATION 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.
Mosquitoes tend to be most active from dusk into the night. Spraying the shaded sides of trees and buildings during the day while they are resting is a common approach to eradication.
Drug resistance <ul><li>Plasmodium develops resistance to drugs </li></ul>
Artemisinin combination therapy Artemisinin is a new drug which is effective if used in combination with other drugs. It is believed that resistance is much less likely to develop against A.C.T.
Background 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.
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…