(A) Course of P chabaudi adamiinfection in C57BL/6J controls (○; n = 5) and transgenic mice expressing 40% to 60% α₂^Mγ₂hemoglobin (•; n = 4). Mice were infected intraperitoneally with 1 × 10⁵ infected erythrocytes on day 9. (B) Mice were injected with 5 × 10⁵ infected erythrocytes on day 0. On the days indicated, smears were prepared from the tail vein, stained, and counted. Data are expressed as mean parasitemia ± standard error of mean (SEM).