Fig. 1

The distribution of MIC values for rifampicin, isoniazid, streptomycin, and ethambutol. The red vertical line is the standard susceptible-resistance threshold (rifampicin 40 μg/ml, isoniazid 0.2 μg/ml, streptomycin 4 μg/ml, ethambutol 2 μg/ml). The two blue vertical lines define the three levels (susceptible, intermediate and full resistance): rifampicin (10, 120 μg/ml), isoniazid (0.05, 3.2 μg/ml), streptomycin (1, 16 μg/ml) and ethambutol (1, 8 μg/ml). MIC minimum inhibitory concentrations