Figure 1. Three cycles of infection and cure are critical for the absolute protection against ECM.

All mice in the four groups were finally challenged with 10⁴ PbA-pRBCs without treatment. Survival and parasitemia were monitored daily. (A) Survival curve of the different cure group mice. Three-cure mice were completely resistant and had significantly improved survival rates compared with the others. Statistical significance was determined by log-rank test. (B) Median parasitemia (%) of mice in all groups over the time of infection. Parasitemia (%) of these groups of mice was performed on days post challenge as indicated and was shown by the box-plots. The upper and lower limits of the box are corresponding to the 25^th and 75^th percentile and the horizontal line inside the box is the median. The whiskers extend to the minimum and maximum values that data assume. Comparisons between each two groups of mice on each day was statistically analyzed by using the nonparametric Mann-Whitney U test, where *, p<0.05. Data shown are representative of two independent experiments; 0-cure mice, n = 3; 1-cure mice, n = 3; 2-cure mice, n = 8; 3-cure mice, n = 5.