Failure to use Chemoprophylaxis when visiting malaria endemic countries.

CDC received reports of 1,505 cases of malaria among persons in the United States, including one transfusion-related case and one fatal case, with onset of symptoms in 2007. The highest estimated relative case rates of malaria among travelers occurred among those returning from West Africa. Of 701 U.S. civilians who acquired malaria abroad, 441 (62.9%) reported that they had not followed an appropriate chemoprophylactic drug regimen. Persons at risk for malaria infection should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel and use personal protection measures to prevent mosquito bites.