Malaria is one of the most common infectious diseases and an enormous public-health problem. The disease is caused by protozoan parasites of the genus Plasmodium. The most serious forms of the disease are caused by Plasmodium falciparum and Plasmodium vivax, but other related species (Plasmodium ovale and Plasmodium malariae) can also infect humans. This group of human-pathogenic Plasmodium species are usually referred to as malaria parasites.

Malaria parasites are transmitted by female Anopheles mosquitoes. The parasites multiply within red blood cells, causing symptoms that include fever, anemia, chills, flu-like illness, and in severe cases, coma and death. Malaria transmission can be reduced by preventing mosquito bites with mosquito nets and insect repellents, or by mosquito control by spraying insecticides inside houses and draining standing water where mosquitoes lay their eggs.