QUESTION

What are the causes of malaria?

ANSWER

Malaria is caused  by infection with certain single-celled parasites of the genus Plasmodium. Specifically, there are five species which infect humans: P. falciparum (the most severe and dangerous form of malaria), P. vivax, P. ovale, P. malariae and P. knowlesi.

The symptoms of the disease occur when the parasite enters the blood stream (after a brief 1-3 week period of development in the liver) and begins to enter red blood cells, reproduce inside them, and then burst out, destroying the cell. The debris caused by this bursting, as well as various other aspects of the process, cause the body to mount an intense immune reaction which results in high fever, chills, aches and nausea. For P. falciparum infection, the infection is particularly severe because the parasite causes red blood cells it infects to stick inside the small blood vessels that lead to major organs, reducing blood flow and causing oxygen deprivation. When this occurs in the blood vessels in the brain, the result is impaired consciousness, unconsciousness, coma and even death – hallmarks of what is known as “cerebral malaria,” which is implicated in many of the deaths related to malaria each year.