Although isolated cases of malaria still may be acquired in the United States,’ imported cases in international travelers are primarily responsible for approximately 1,000 cases reported annually to the Centers for Disease Control and Prevention (CDC). In the decade ending in 1988, more than 50 malaria-associated deaths were reported, most of them theoretically preventable. Moreover, it is estimated that only 30% to 60% of malaria cases are actually reported to the CDC.
In recent years, an increase in infections due to Plasmodium falciparum, which accounts for the most severe form of malaria, has been noted. This increase is multifactorial in origin and is associated with an increase in travel to malarious areas, difficulties with chemoprophylaxis (including compliance and adverse effects), and increasing resistance to multiple antimalarial agents. Thus, careful counseling of the traveler and appropriate chemoprophylaxis remain vitally important.