Fig 5.
Virulence phenotypes of blood and ear isolates. Groups of 15 mice were infected intranasally with 107 CFU of the indicated strain. At the indicated times, 5 mice from each group were euthanized and numbers of pneumococci in the indicated tissues were quantitated. (A) Nasopharyngeal tissue; (B) ear; (C) blood. Viable counts are shown for each mouse at each site; horizontal bars indicate the median value for each group/time point. Blood isolates are represented by solid symbols; ear isolates are represented by open symbols. Differences between groups were analyzed by 1-tailed Mann-Whitney U test (*, P < 0.05; **, P < 0.01; and ***, P < 0.001).