FIG. 2.
Distribution of the 97 L. monocytogenes strains according to the MICs of cetrimide. Two populations were observed. One group scored as susceptible, consisted of 90 strains for which the MICs were ≤14 mg/liter. The second group, scored as less susceptible, consisted of 7 strains for which the MICs were ≥20 mg/liter. These seven strains were also less susceptible to benzalkonium chloride.