The MMWR for June 25, 2010 / Vol. 59 / No. SS–7 includes: Malaria Surveillance — United States, 2008
Abstract
The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing malaria transmission. CDC received reports of 1,298 cases of malaria with an onset of symptoms in 2008 among patients in the United States, a decrease of 13.8% from the 1,505 cases reported for 2007 (p<0.001). The first documented case of simian malaria, Plasmodium knowlesi, was reported in a U.S. traveler. The highest estimated relative case rates of malaria among travelers occurred among those returning from countries in West Africa. In the majority of reported cases, U.S. civilians who acquired malaria abroad had not adhered to a chemoprophylaxis regimen that was appropriate for the country in which they acquired the infection. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should always include blood-film tests for malaria with results available immediately. Malaria infections can be fatal if not diagnosed and treated promptly.

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