Abstract
Malaria is the world's most important parasitic disease, accounting for an estimated 300 to 500 million new cases and between 1.5 and 2.7 deaths annually. The majority of these deaths occur in sub-Saharan Africa where malaria is endemic and are the result of infection with Plasmodium falciparum. The number of deaths in the United States due to malaria is comparably much lower and involves so-called “imported” cases in which U.S. travelers acquire the infection upon travel to endemic areas and subsequently return to the United States or in which infected foreign citizens travel to the United States.
There were a total of 118 deaths due to malaria in the United States between 1979 and 1998 with an average of 5.9 deaths per year. Specific epidemiological data provided by the CDC regarding the 40 deaths that occurred between 1992 and 1998 yielded the following results. Deaths occurred in patients ranging from 9 months to 89 years of age (median, 53 years). Thirty-eight (95%) of these were due to P. falciparum and two (5%) due to P. vivax. Anti-malarial chemoprophylaxis was taken in 40% of cases, not taken in 45% of cases, and unknown in 15% of cases. Twenty-four (60%) of the cases involved U.S. travelers to endemic areas, of whom 59% traveled to Africa, 25% to South America, 8% to India, 4% to Haiti, and 4% to unspecified areas. The remaining cases included eleven foreign travelers to the U.S. (27.5%), three induced cases (7.5%), and two undetermined cases (5%). Thirty-nine (98%) of the cases were diagnosed antemortem and only one case was known to have come to the attention of the medical examiner/coroner.
An illustrative case report demonstrates many of the features associated with fatal malaria infections in the United States. The case involves a U.S. student who was studying in Africa and who, by report, had not taken antimalarial chemoprophylaxis. Despite seeking medical attention, the patient was not diagnosed with P. falciparum infection and cerebral malaria until the time of medico-legal autopsy, where the classic gross and microscopic features of cerebral malaria were identified.
This case represents one of the few cases of P. falciparum infection in the United States not diagnosed antemortem. Given the worldwide prevalence of the disease, increasing international travel, and rapidly developing drug resistance, malaria will continue to be an important disease and should be considered in cases of sudden, unexplained deaths. By reviewing the major epidemiological features of malaria-related deaths in the United States and by presenting the major gross and microscopic features of cerebral malaria, an attempt is made at raising the awareness of the forensic community to the potential of malaria-related deaths.
