Fig. 1.

P. fragile and SIV-P. fragile animal models. The data show the correlation between hematocrit (dotted line) and parasitemia, measured as the percentage of infected RBC per total RBC by blood smear (solid red line) or as total copies of P. fragile DNA per total RBC by PCR analysis (solid black line) in P. fragile-infected (A) and SIV-P. fragile-coinfected (B and C) animals. Asterisks indicate the time of quinine sulfate treatment. A 2-day treatment effectively induced chronic parasitemia in P. fragile-only-infected (A), but not in SIV-P. fragile-coinfected (B) animals. (C) Chronic parasitemia in SIV-P. fragile-coinfected animals was induced by a 4-day quinine sulfate treatment.