Figure 7. Comparison of therapeutic and post-exposure vaccine efficacy.

(A) In the therapeutic model, CB6F1 mice were aerosolly infected and vaccinated three times with two weeks interval starting at week 6 post infection (p.i.) (black arrows) with ESAT-6/CAF01 (open circle) or CAF01 alone (open triangle). The therapeutic efficacy was assessed at week 21 p.i. Data shown are median values ± interquartile range week 0-20 from 3-8 individual animals and at week 21 p.i. n=7 for control animals and n=8 for ESAT-6 vaccinated. The two groups were compared with a Mann Whitney U-test and p<0.05 was considered significant. (B) In the post-exposure model, mice were infected for six weeks and then given antibiotics for six weeks, as described in materials and methods. Groups of mice were vaccinated with ESAT-6/CAF01 or CAF01 alone at week 10, 12 and 14 p.i. (black arrows) and protection assessed at week 18, 27 and 40 p.i. by culturing lung homogenates and enumerating the number of bacteria (expressed as log₁₀). Data shown are median values ± interquartile range for the control group (open triangles, n=6) and ESAT-6 vaccinated group (open circle, n=6). Values marked with an asterisk are significantly different from naïve control animals as assessed by non-parametric Mann-Whitney U-test (**, p<0.01, *, p<0.05).