Figure 4.

Parasite density in mouse tissues. The parasite burden in mice (number of T. gondii per gram) was determined by quantitative PCR and the graph shows the average values plus standard deviation for one type III strain (three mice), one type II/III strain (two mice) and six type II strains (17 mice). The type III strain (TgCkUg6) caused the highest burden, followed by the recombinant strain (TgCkUg2), while the six type II strains (TgCkUg1, 3, 5, 7, 8, 9) had significantly lower densities. In all mice, the brain was the most heavily infected tissue.