Causes
By Mayo Clinic staffMalaria is caused by a type of microscopic parasite that's transmitted most commonly by mosquito bites.
Mosquito transmission cycle
- Uninfected mosquito. A mosquito becomes infected by feeding on a person who has malaria.
- Transmission of parasite. If you're the next person this mosquito bites, it can transmit malaria parasites to you.
- In the liver. The parasites then travel to your liver — where they can lie dormant for as long as a year.
- Into the bloodstream. When the parasites mature, they leave the liver and infect your red blood cells. This is when people typically develop malaria symptoms.
- On to the next person. If an uninfected mosquito bites you at this point in the cycle, it will become infected with your malaria parasites and can spread them to the next person it bites.
Other modes of transmission
Because the parasites that cause malaria affect red blood cells, people can also catch malaria from exposures to infected blood, including:
- From mother to unborn child
- Through blood transfusions
- By sharing needles used to inject drugs
- Ferri FF. Ferri's Clinical Advisor 2013: 5 Books in 1. Philadelphia, Pa.: Mosby Elsevier; 2012. http://www.mdconsult.com/books/about.do?eid=4-u1.0-B978-0-323-08373-7..00002-9&isbn=978-0-323-08373-7&about=true&uniqId=343863096-23. Accessed Oct. 16, 2012.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Oct. 16, 2012.
- Malaria: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/malaria/about/faqs.html. Accessed Oct. 16, 2012.
- Laishram DD, et al. The complexities of malaria disease manifestations with a focus on asymptomatic malaria. Malaria Journal. 2012;11:1.


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