Direct species identification from clinical samples. (A-D) Representative melt curves and amplification curves (inset) from clinical samples with Plasmodium falciparum (A), Plasmodium malariae (B), Plasmodium ovale (C), and Plasmodium vivax (D) following real-time PCR with species-specific primers. Amplification curves are shown in triplicate but single melt curves are shown for clarity. Negative controls (gray) are from uninfected blood. The stippled line marks the threshold for the amplification curves.