Malaria Prevention in a Nutshell

(Mosquito larvae. Photo credit: Alvaro Rodriguez)

Because malaria is transmitted only by the Anopheles mosquito, preventing malaria transmission is a viable, cost-effective option for reducing malaria when used in conjunction with effective treatment. The methods of preventing transmission include insecticide-treated bednets, indoor residual spraying, reduction of mosquito habitats, and preventative treatment for individuals at risk for malaria.

Bednets are hung over beds, to prevent night-time mosquito bites. Since mosquitoes do most of their biting at night, bednets can reduce malaria transmission by as much as 90% in areas with high usage. They are impregnated with a long-lasting insecticide to both kill and repel mosquitoes.

Habitat Reduction involves reducing mosquito breeding by draining the standing water in which their eggs hatch. Mosquitoes can lay eggs in very small amounts of water, so removing stagnant water from locations like old tires, mud puddles, or deep holes can cut down on transmission. Mosquitoes lay their eggs in so many locations, however, that habitat reduction is effective only on a household level, not a national level.

Indoor Residual Spraying (IRS) is exactly what it sounds like. The inside walls and other surface in houses are sprayed with pesticides designed to last for a long time. IRS does not prevent the mosquitoes from biting, but it kills them afterward, when they land on household surfaces, and stops mosquito reproduction and malaria transmission. To be effective, IRS must be applied to at least 70% of households in an area.

Preventative treatment is provided to the two groups most at risk for death from malaria, pregnant women and infants. They get either steady or intermittent doses of the same drugs that treat malaria. It cannot keep them from becoming infected, but it will eliminate the malaria parasites that cause symptoms.