Experimental setup of mixed infection of experiments 1 and 2.

Infections were initiated with a mixture of resistant and susceptible parasites with the specified R∶S ratio inoculum on day 0 (Experiment 1) or with 106 susceptible parasites on day 0 and ∼25 resistant parasites on day 5 (Experiment 2). Number of mice at the start of the experiment is given, with the number used in the analysis (after exclusion based on infection establishment and mortality; see Materials and Methods for details) in brackets.