Malaria is a serious illness caused by parasites of the Plasmodium species . There are four different types of malaria that infect humans, including falciparum, vivax, malariae and ovale. Of these, falciparum malaria is the most serious. This disease is a leading cause of illness worldwide, with 300 - 500 million cases reported each year. In 2003, there were 207 cases of malaria reported among New York City residents who had traveled to areas of the world where malaria is present (rate of 2.5 cases per 100,000 persons).
Any person who lives in or travels to a country where malaria is present is at risk for infection with malaria. Malaria is common in tropical or subtropical areas of Asia, Africa, and Central and South America. The risk of malaria may be different between countries and between areas of a country.
Malaria is spread by the bite of an infected female Anopheles mosquito. These mosquitoes generally bite during the evening or early night time hours. In some cases, malaria has been transmitted by transfusion of blood from infected people or by the use of contaminated needles or syringes. It is also possible for a pregnant mother to transmit malaria to her fetus (congenital malaria).
Malaria infection can be life-threatening. Symptoms include fever, chills, sweats, and headache, and in some instances may progress to jaundice (yellowing of the skin and eyes), bleeding, shock, kidney or liver failure, delirium, and coma. When malaria symptoms start, they may be similar to the flu. Cycles of chills, fever, and sweating occurring every one to three days are characteristic of malaria. People returning from an area where malaria occurs who become ill should see a doctor immediately.
The time between the infective mosquito bite and the development of symptoms can range from 7 to 30 days depending on the type of malaria-causing parasite involved. In some cases, a person may not develop a symptomatic malaria infection until years after travel to the malaria endemic area. This would generally only occur among people who lived for a long time in the malarious area.
Direct person-to-person transmission does not occur. Malaria infection is spread through the bite of an infected mosquito (anopheline).
The diagnosis of malaria is made by microscopic identification of the parasite on a blood smear. New techniques to identify parasites in the bloodstream, such as PCR (polymerase chain reaction), are also available.
The treatment of malaria will depend on where the person was when the infection occurred, and the type of malaria-causing parasite involved. Several drugs are available for treatment such as quinine, chloroquine, and doxycycline. Anyone with symptoms of malaria should talk to their doctor before starting any treatment.
Persons traveling to areas where malaria is common should talk to their doctor about the need for preventive medicine. These preventive medicines usually need to be started before traveling to a malarious area and continued for several weeks after returning. Other important ways to prevent malaria include:
For detailed information about malaria risk and recommendations for travelers please visit www.cdc.gov/travel. Traveler's should review preventive recommendations before travel