 Each participant in the cohort will be inoculated on Day 0 with 1,800 viable parasites of Plasmodium falciparum-infected human erythrocytes BSPC administered intravenously. On an outpatient basis, participants will be monitored daily via phone call and then daily AM from day 4 until PCR positive for presence of malaria parasites. Once PCR positive they will be monitored twice-daily morning AM and evening PM until treatment, for adverse events and the unexpected early onset of symptoms, signs or parasitological evidence of malaria. On the day designated for commencement of treatment, as determined by qPCR results, participants will be admitted to the study unit and monitored. The threshold for commencement of treatment will be when PCR quantification of all participants is 1,000 parasitesmL. If the PCR quantification of any participant is 5,000 parasitesmL and is accompanied by a clinical symptom score 5, or if clinical or parasitological evidence of malaria occurs in any participant before all participants have reached the treatment threshold PCR quantification of 1,000, then treatment of that participant will begin within a 24 h period. 