Blood smears from a 3-year-old boy with acute malaria and G6PD deficiency treated with chlorproguanil-dapsone. (A) Pretreatment: black arrows point to erythrocytes parasitized by P falciparum (ring forms), the white arrow points to an erythrocyte containing 2 rings of P falciparum. (B) Approximately 24 hours after starting treatment (day 1): on the left abnormally shaped parasites are seen within spherocytes, on the right a parasite in a severely contracted erythrocyte. (C) On day 3: numerous contracted erythrocytes, spherocytes, and hemighosts (often referred to as “bite cells”; arrows). Inset: another hemighost at a greater magnification; the part of the erythrocyte that appears to be missing is the negative image of a Heinz body.⁵¹  Slides were prepared with Giemsa stain and Zeiss immersion oil. An Orthoplan light microscope was used (Leitz). Panel C (except the inset) was taken with an objective Plan-Apochromatic ×63 oil, aperture number 1.4 (Zeiss). The inset to panel C and all other photos were taken with objective ×100 oil, aperture number 1.3 (Leitz). Imaging was with a ProgRes C10plus (Jenoptik-Laser Optik Systeme) with acquisition software ProgRes Capture Basic (Jenoptik) running under Windows XP on a personal computer (assembled).