. 2004 Mar;42(3):1185–1191. doi: 10.1128/JCM.42.3.1185-1191.2004

TABLE 3.

Distribution of the strain collection according to current NCCLS criteria for fluoroquinolone-susceptible H. influenzae and comparison with data on amino acid modifications in the QRDRs of GyrA and ParC

Quinolone	NCCLS criteria (μg/ml)^a	Proposed zone diameter (mm)^b	No. (%) of strains with:
Quinolone	NCCLS criteria (μg/ml)^a	Proposed zone diameter (mm)^b	No mutation	One mutation in GyrA QRDR	Two mutations in either GyrA or ParC QRDR
Ciprofloxacin	≤1	≥28	34 (81)	5 (12)	3 (7)
Levofloxacin	≤2	≥18	33 (60)	7 (12.7)	15 (27.3)
Moxifloxacin	≤1	≥23	33 (76.7)	5 (11.6)	5 (11.6)

The NCCLS criteria are presented in reference 23.

These proposed diameters were based on the distribution of the population in Fig. 2.