TABLE 3.
Mutation in gyrA gene in Salmonella serovar Virchow isolates
| Nalidixic acid MIC (μg/ml) | Ciprofloxacin MIC (μg/ml) | No. of isolates | PFGE result | GyrA mutation |
|---|---|---|---|---|
| Resistant isolates | ||||
| 128-512 | 0.125-0.25 | 78 | A1 (43%), B1 (30%), A4 (8%), A3 (5%), B2 (4%), A2 (4%), B6, B7, A6, A9 (1.3%) | Asp87-Tyr |
| 0.125 | 7 | A1 (29%), B1 (42%), A4 (29%) | No mutation | |
| 128 | ≤0.03 | 2 | A1 (100%) | No mutation |
| Resistanta | Susceptiblea | 26 | B1 (58%), A1 (23%), B4 (12%), A10 (4%), A4 (4%) | Asp87-Tyr |
| Sensitive isolates | ||||
| ≤8 | ≤0.03 | 3 | B1 (33%), A1 (33%), A3 (33%) | No mutation |
| 4 | ≤0.03 | 1 | A1 | Asp87-Tyr |
a
MICs were not determined; disk diffusion was performed.