|Agricultural Development and Vector-Borne Diseases (FAO - HABITAT - UNEP - WHO, 1996, 91 p.)|
|Topic A: Vector-borne diseases of relevance to agriculture|
Slide A.8 Girl suffering from malaria, the Gambia
The clinical symptoms of malaria are reasonably clear, but the underlying pathology complex. The traditional fever and headache syndrome is related to the breakdown of parasitized red blood cells and the release of the parasites waste products in the blood stream are accompanied by liver and spleen enlargement and anemia. With a high concentration of parasites in the circulation, the P. falciparum feature of parasites clumping together in the small blood vessels of brain may cause severe cerebral malaria, which can be fatal in a matter of 24 hours.
The great majority of fatalities caused by malaria is among under five year olds in sub-Saharan Africa (rough estimates come to the figure of 1 million deaths a year); pregnant women are another vulnerable group; and migrants from non-malarious (usually high-altitude) areas moving into new development schemes (particularly irrigation schemes) make up a third important group.
Attribution of malaria transmission to a single environmental or behavioural factor is impossible. Moreover, malaria being a disease of poverty, it is usually part of a conglomerate of illnesses, including diarrhoeal diseases, malnutrition and other parasitic infections.