What is malaria and what are its symptoms?
Malaria is an infectious disease transmitted by the bites of mosquitoes infected with the malaria-causing parasite. After being bitten by an infected mosquito, the parasite infects human liver and red blood cells. Most malaria infections cause flulike symptoms (such as high fever, chills, muscle pain, diarrhea) that come and go in cycles as the disease progresses. One type of malaria may cause more serious problems, including heart, lung, kidney, or brain damage and possibly death.

How do people become infected?
You can become infected with malaria when you are bitten by a certain type of mosquito (Anopheles mosquitoes) infected with the malaria parasite. In rare cases, people can get malaria if they come into contact with infected blood or a fetus may get the disease from its mother. You cannot get malaria by being near a person with the disease.

Where is malaria found?
Malaria occurs most frequently in tropical Africa, parts of Asia, Central America, and South America. It occurs less frequently in Greece, Turkey, and the Middle East. Poor sanitation in some of these countries contributes to the severity of malaria by providing ideal conditions for mosquitoes to breed. In the United States, most malaria cases occur in people who have traveled in areas where malaria is present and in immigrants from those areas.

How is malaria prevented?
Malaria can usually be prevented by taking medication before, during, and after travel to an area where malaria is present and by protecting yourself against mosquito bites. Although the use of medications to prevent malaria is recommended and generally effective, it does not always prevent infection. This is partly because some parasites that cause the disease are becoming more resistant to some preventive medications.

How is malaria treated?
Malaria often requires treatment with medication (antimalarial medications). Antimalarial medications are usually effective in treating the infection; however, the effectiveness of medications both to prevent and treat the disease depends on the medication resistance of the malaria parasites you are exposed to.