UNDER THE MICROSCOPE
Malaria is transmitted by the saliva of infected mosquitoes when they bite humans. Parasites in the saliva enter the bloodstream, and invade red blood cells. They multiply inside these cells and then burst out, killing the cells and increasing the infection.
Four variants of the same parasite cause malaria. The most common are Plasmodium falciparum and Plasmodiumvivax. While P. vivax is the most common, causing an estimated 80 per cent of cases, P. falciparum is the most deadly. The two other variants are P.ovale and P.malariae.
While many species of mosquito can transmit any of a long list of infectious diseases, malaria is only transmitted by 30 to 40 of the 400 different species of mosquito in the Anopheles genus— itself just one of 41 genera (the plural of genus) that make up the Culicidae family in which mosquitoes are classified.
Malaria is not a threat in Australia, but there was an outbreak in Queensland in 2002 and the far north is considered receptive to the disease being reintroduced.
Worldwide 2.5 billion people are at risk of malaria — about 40 per cent of the world’s population.
Most deaths and infections occur in Africa, where malaria kills one child every 30 seconds.
Early diagnosis and prompt treatment are two basic elements of malaria control. This can shorten the duration of the infection and prevent further complications including the great majority of deaths.
Long-lasting insecticide-impregnated bed nets, effective for between three and five years, can be used to provide protection to risk groups, especially young children and pregnant women in high transmission areas.
Pregnant women are at high risk not only of dying from the complications of severe malaria, but also spontaneous abortion, premature delivery or stillbirth.