What is it?
Malaria is a widespread vector-borne disease caused by parasites in the Plasmodium family (specifically Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae) and transmitted by the bite of an infected female Anopheles mosquito. Each year between 300 and 500 million people are infected and more than one million people die, most of them children and pregnant women. Malaria is associated with tropical and subtropical climates because the warm temperature allows the Anopheles mosquito to grow year round.
Causes of malaria
A female Anopheles mosquito ingests a blood meal from an infected person which contains gametes. Fertilization occurs in the mosquito’s gut and sporozoites develop which are then injected into the next host when the mosquito feeds. The sporozoites travel to the new host’s liver and develop into merozoites which then penetrate red blood cells and develop into gametes which are taken up by another mosquito.
The economic impact of malaria on poor countries and individuals is enormous, with some highly affected countries spending significant portions of public health care funding on malaria treatment. Individuals with malaria not only pay significant portions of their personal income on treatment but also suffer decreased attendance at work and schools, perpetuating a cycle of poverty.
There are no vaccines against malaria. Malaria control is divided into two categories, prevention and treatment. When in a high risk area for malaria people are encouraged to use insect repellent containing DEET and to wear long sleeves and pants to avoid being bitten by mosquitos. Sleeping under a treated sleep net also prevents being bitten and being infected. Once a person is infected there are several drugs that can be used that target the parasite in the blood including chloroquine, sulfadoxine-pyrimethamine, mefloquine, atovaquone-proguanil, quinine, and doxycycline. However, widespread use of these drugs and poor health care management has resulted in the development of resistance especially against chloroquine. Additionally the Anopheles mosquito has developed resistance to many of the commonly used insecticides, making prevention efforts more difficult.