Plasmodium malariae and P. falciparum parasite gene copy numbers (per microliter) and parasitemia (parasites per microliter) in co-infected samples. Median, first quartile, and fourth quartile of the data are shown for each sample category (horizontal lines). Parasite gene copy number and parasitemia were lower in P. malariae–positive than in P. falciparum–positive samples. Squares represent samples with gene copy number measured by quantitative PCR; circles, samples with parasitemia estimated by microscopy; red, P. malariae samples; blue, P. falciparum samples.