Malaria Katie Jeon Malaria, one of the common diseases, is caused by protozoan parasites of the genus Plasmodium (phylum Apicomplexa). In humans, malaria is caused by P.falciparum, P.malariae, P.ovale, and P.vivax. Malaria is found in tropical and subtropical climates, mostly Africa, South America, the Middle East, India, and all of the southeast Asia, because Malaria-carrying mosquitoes, Anopheles mosquitoes, require temperatures of more than 68 degrees Fahrenheit. The Anopheles mosquitoes actively multiply and spread the disease in the rainy season. In drier areas, outbreaks of malaria can be predicted with reasonable accuracy by mapping rainfall.

Symptoms of Malaria The usual symptoms characteristic of malaria include flu-like illness with fever, chills, muscle aches, and headache. Some patients develop nausea, vomiting, cough, and diarrhea. Cycles of chills, fever, and sweating that repeat every one, two, or three days are typical. There can sometimes be vomiting, diarrhea, coughing, and yellowing (jaundice) of the skin and whites of the eyes due to destruction of red blood cells and liver cells. People with severe P. falciparum malaria can develop bleeding problems, shock, liver or kidney failure, central nervous system problems, coma, and can die from the infection or its complications. Cerebral malaria (coma, or altered mental status or seizures) can occur with severe P. falciparum infection. It is lethal if not treated quickly; even with treatment, about 15%-20% die.

How is Malaria spread? Malaria is transmitted to humans when an infected Anopheles mosquito bites a person and injects the malaria parasites (sporozoites) into the blood through the bloodstream to the liver, mature. Sporozioites in the mosquito’s saliva enter the bloodstream and migrate to the liver. Within 30 minutes of being introduced into the human host, they infect the liver, multiplying asexually and asymptomatically for a period of 6- 15days. They escape the liver into the blood and infect red blood cells. Within the red blood cells, the parasites asexually multiply further and periodically break out of their hosts to invade fresh red blood cells. Usually, the parasite is relatively protected from attack by the body’s immune system. However, the P.falciparum parasite displays adhesive proteins on the surface of the infected blood cells, causing the blood cells to stick to the walls of small blood, to avoid being destroyed in the spleen. So the immune system can not destroy the red blood cell surface adhesive proteins because of their extreme diversity. That is why the P. falciparum is the most severe type among four Malarias.

Where the term comes from The term malaria originates from Medieval Italian: mala aria — "bad air" in 1740 by H. Walpole when describing the disease; and the disease was formerly called ague or marsh fever due to its association with swamps. The term was shortened to "malaria" in the 20th century. C. Laveran in 1880 was the first to identify the parasites in human blood.