Figure 2

Scattergrams correlating the MICs of ciprofloxacin to those of other fluoroquinolones. Scattergrams for 816 Salmonella strains correlating the minimum inhibitory concentrations (MIC) of ciprofloxacin to those of clinafloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin, and sitafloxacin. The numbers within the graphs indicate the numbers of Salmonella strains. The vertical solid lines indicate the Clinical and Laboratory Standards Istitute (CLSI) breakpoint recommendations for susceptibility and resistance, respectively, to ciprofloxacin (MIC ≤1 and ≥4 μg/ml); and the vertical dashed lines, the breakpoint for reduced susceptibility (MIC ≥0.125 μg/ml). The horizontal solid lines indicate the respective CLSI breakpoint recommendations to those fluoroquinolones for which such recommendations are available: ofloxacin (MIC ≤2 and ≥8 μg/ml); norfloxacin (MIC ≤4 and ≥16 μg/ml); and levofloxacin (MIC ≤2 and ≥8 μg/ml).