Making antimalarial agents available in the United States

Selective ambulatory management of imported falciparum malaria: a 5-year prospective study

The ambulatory management of imported Plasmodium falciparum malaria is controversial because criteria for safe selection of patients are imprecise. The aim of the present study was to investigate the evolution and outcome of patients diagnosed with Plasmodium falciparum malaria at a Belgian referral institute in order to assess the safety of the institute's current selective ambulatory management protocol. From 2000 to 2005, all patients diagnosed with P. falciparum infection at the Institute of Tropical Medicine and the University Hospital of Antwerp were enrolled prospectively. Ambulatory treatment was offered to nonvomiting patients if they exhibited none of the 2000 World Health Organization criteria of severity and had parasitemia below 1% at the initial assessment. The treatment of choice was quinine (plus doxycycline or clindamycin) for inpatients and atovaquone-proguanil for outpatients. P. falciparum malaria was diagnosed in 387 patients, of whom 246 (64%) were Western travelers or expatriates and 117 (30%) were already on antimalarial therapy. At diagnosis, 60 (15%) patients had severe malaria. Vital organ dysfunction was initially seen in 34 and developed later in five others. Five patients died. Of the 327 patients initially assessed as having uncomplicated malaria, 113 (35%) were admitted immediately; of these, 4 developed parasitemia >/=5% at a later stage but without any clinical consequence. None of the 214 individuals initially treated as outpatients experienced any malaria-related complications, including 10 who were admitted later. Vital organ dysfunction was observed in only 2 of the 214 patients with initial parasitemia <1% who had not taken antimalarial agents (both patients had impaired consciousness at presentation). Ambulatory treatment is safe in treatment-naive malaria patients with parasitemia <1% who do not vomit and who do not exhibit any criteria of severe malaria.

Role of US military research programs in the development of US Food and Drug Administration--approved antimalarial drugs

US military physicians and researchers helped identify the optimum treatment dose of the naturally occurring compound quinine and collaborated with the pharmaceutical industry in the development and eventual US Food and Drug Administration approval of the synthetic antimalarial drugs chloroquine, primaquine, chloroquine-primaquine, sulfadoxine-pyrimethamine, mefloquine, doxycycline, halofantrine, and atovaquone-proguanil. Because malaria parasites develop drug resistance, the US military must continue to support the creation and testing of new drugs to prevent and treat malaria until an effective malaria vaccine is developed. New antimalarial drugs also benefit civilians residing in and traveling to malarious areas.

Malaria: Diagnosis and treatment of falciparum malaria in travelers during and after travel

Plasmodium falciparum is responsible for most of the mortality in travelers related to imported malaria. Problems that occur during travel include the inaccuracy of a microscopic diagnosis of malaria, both false positives and false negatives, when ill travelers seek care while abroad. A false positive diagnosis can result in unnecessary parenteral injections that carry a risk of transmission of blood-borne pathogens, receipt of potentially dangerous drugs such as halofantrine, or receipt of fake, counterfeit drugs. Increased morbidity and mortality are associated with delays in diagnosis and initiation of prompt treatment for falciparum malaria. Availability of expert microscopy to confirm the diagnosis of malaria is limited. The presence of splenomegaly and thrombocytopenia are strongly associated with malaria and would justify empiric treatment. The availability of atovaquone-proguanil, a safe and well tolerated oral drug, should prompt a reconsideration of current treatment recommendations that discourage empiric treatment on clinical suspicion alone.