A 33-year-old Australian woman, who had been stationed in Liberia for 4 months, flew to New York City for vacation. Several days later, she developed fever, rigors, lower back pain, and headache. On the third day of symptoms, she was acutely ill and was admitted to The New York Hospital where a peripheral blood smear showed characteristic ring forms of Pfalciparum (Figure 1). She had discontinued chloroquine and proguanil prophylaxis due to gastrointestinal intolerance 10 weeks before admission. Initial laboratory studies included white blood cell (WBC) count of 4800/mm3; hemoglobin, 11.9 g/dL; hematocrit, 34%; platelet count, 43,000/mm3; lactic dehydrogenase (LDH), 399 IU; prothrombin time (PT), 14.7 seconds (control 12.0 s); and partial thromboplastin time m, 35.1 seconds (control 38 s). Admission chest examination and roentgenogram were normal (Figure 2, A). After 18 hours of treatment with oral quinine and doxycycline, parasitemia was reduced from 2. IL to 1.2%. However, 12 hours later, the patient developed acute respiratory distress with severe hypoxemia (arterial PO, 38 mmHg breathing room air). Bronchial breath sounds and rales were heard over both lower lung fields. Fever to 39°C persisted, although parasitemia was less than 0.1%. The patient developed evidence suggesting coagulopathy or disseminated intravascular coagulation (DIG) with a further increase in PT to15.4 seconds and a positive D-dimer test. Repeat chest x-ray was consistent with