Malaria is a life-threatening mosquito-borne blood disease caused by a Plasmodium parasite.
Malaria is a serious and sometimes fatal disease caused by a parasite that infects a type of mosquito which feeds on humans. Once an infected mosquito bites a human, the parasites multiply in the host’s liver before infecting and destroying their red blood cells. People who get malaria are usually very sick with symptoms such as high fevers, shaking chills, and flu-like illness.
It is transmitted to humans through the bite of the Anopheles mosquito.
Over 100 types of Plasmodium parasite can infect a variety of species. They replicate at different rates, and this affects how fast the symptoms escalate, and the severity of the disease.
Four kinds of malaria parasites infect humans: Plasmodium falciparum, P. vivax, P. ovale, and P. malariae. They are found in different parts of the world. Some cause a more severe type of malaria than others.
In addition, P. knowlesi, a type of malaria that infects macaques in Southeast Asia, also infects humans, causing malaria that is transmitted from animal to human (“zoonotic” malaria). P. falciparum is the type of malaria that is most likely to result in severe infections and if not promptly treated, may lead to death. In some places, malaria can be treated and controlled with early diagnosis. However, some countries lack the resources to do this effectively.
Currently, no vaccine is licensed for use in the United States (U.S.) or globally, although one is available in Europe. Malaria was eliminated from the U.S. in the early 1950s, but between 1,500 and 2,000 cases still occur each year, mostly in those who have recently traveled to malaria-endemic areas. The vast majority of cases in the United States are in travelers and immigrants returning from parts of the world where malaria transmission occurs, including sub-Saharan Africa and South Asia.
Globally, the World Health Organization estimates that in 2015, 212 million clinical cases of malaria occurred, and 429,000 people died of malaria, most of them children in Africa. Because malaria causes so much illness and death, the disease is a great drain on many national economies. Since many countries with malaria are already among the poorer nations, the disease maintains a vicious cycle of disease and poverty.