|  | Conditions Treatments | Medical Conditions

Causes of Malaria

Malaria is an infectious disease that affects approximately 200 million to 300 million people worldwide each year, killing close to 3 million people. Malaria is particularly a problem in countries with hot, humid climates and large mosquito populations.

  1. Definition

    • Malaria is a disease in which parasites that disable red blood cells enter the body. When a mosquito infected with the malaria-causing parasite bites a human, the parasite is introduced into the bloodstream, where it travels to the liver and matures. After the parasites reach maturity, they invade and multiply within the individual's red blood cells, causing the blood cells to burst and releasing newly matured parasites that will continue the cycle of destruction.

      While there are four ways in which humans can become infected with malaria, all begin with the parasite-infected mosquito.

    Direct infection

    • The most common cause of malaria is by direct infection from a mosquito carrying the parasite Plasmodium. There are four types of malaria-causing strains of Plasmodium. While all four cause the signs and symptoms of malaria, Plasmodium falciparum is the most deadly.

    Indirect infection

    • Infection with the Plasmodium parasite can also occur when an uninfected mosquito bites a person already infected with malaria. The mosquito then becomes infected with the parasite and can pass the infection to previously unaffected humans through its bite.

    Blood Transfusion

    • In a number of developing countries that suffer from malarial outbreaks, inadequate health-care facilities make it difficult for blood to be properly screened for the presence of infectious diseases and malaria-causing parasites before being used in emergency medical procedures. In these countries, becoming infected with malaria from infected blood is less common than infection from mosquitoes, but is still a danger.

    Contaminated Needles

    • Whether used in medical procedures or by individuals with a drug addiction, shared or reused needles and syringes can be a source of malarial infection, if one of the individuals has been previously infected with the Plasmodium bacteria. As with blood transfusions of infected blood, contracting malaria from a contaminated needle is mainly a problem in developing countries with inadequate health-care resources.

Medical Conditions - Related Articles