Comparison of fitted survival curves for mice infected with
A1a, A1b, A2, type B and Schu S
. Survival curves were modeled previously [16, 18] according to a Weibull distribution for mice (n = 7/strain) infected intradermally with 10–20 CFU of two strains each of A1a (▬; black), A1b (▬ I ▬; blue), A2 (▬ ▬; red), and type B (▬ III ▬; green), and are compared to the survival curve of Schu S4 infected mice (III ; orange). The time at which each mouse reached drop point is shown below the graph as black squares for A1a infected mice, blue circles for A1b infected mice, red triangles for A2 infected mice, green diamonds for type B infected mice and orange upside-down triangles for Schu S4 infected mice.