Frequently asked questions about malaria

What is malaria?

Malaria is a parasitic infection transmitted to humans through the bites of infected female Anopheles mosquitoes. The resulting disease in humans can be devastating. After moving rapidly to the liver, the parasite moves into the blood stream to settle in the red blood cells, where it multiplies and emerges in bursts of new organisms. These parasites, because of their large numbers, can cause particular damage to the nervous system, liver, and kidneys.

In young children and adults who have not recently been infected (and therefore have not developed natural immunity), this cycle can result in death within hours from cerebral malaria. Others also die from overwhelming anemia or liver and kidney failure. Malaria is a leading cause of death and illness in developing countries, hitting hardest in resource-poor tropical and subtropical areas. Malaria transmission, which is affected by climate and geography, often coincides with the rainy season. The disease kills more than one million people annually, most of them sub-Saharan African children under age five.

What are the different types of malaria?

Four species of the malaria parasite are known to infect humans:

  • Plasmodium falciparum
  • Plasmodium vivax
  • Plasmodium malariae
  • Plasmodium ovale

Among the four species of the malaria protozoan parasite, Plasmodium falciparum is the deadliest.

How is malaria transmitted?

Malaria is transmitted by the female Anopheles mosquito, of which there are more than 40 species. When a mosquito bites an infected person, it takes in a small amount of blood, which contains microscopic malaria parasites. About one week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito’s saliva and are injected into the person being bitten. Malaria may also be transmitted from a mother to her unborn infant before or during delivery.

Who is most at risk of getting very sick and dying from malaria?

Every year, P. falciparum malaria causes the deaths of more than one million people, most of them sub-Saharan African infants and children. Malaria also contributes to anemia in children and pregnant women, low birthweight, premature birth, and neurological damage. An estimated 300 million to 500 million cases of malaria occur every year, and roughly 3.2 billion people are at risk of contracting the disease.

How is malaria treated?

Malaria can be treated with a regimen of antimalarial drugs based on the type of infection and status of the patient.

How is malaria controlled?

Malaria-control strategies include the use of medicines, insecticides, and insecticide-treated screens and bednets. Control programs led to the elimination of malaria from Australia, Europe, and the United States by the 1950s.