Resistance to Quinolones and Tetracycline and Its Molecular Background among Campylobacter Strains Isolated in Poland

The aim of this study was to investigate the resistance to quinolones and tetracycline of 200 C. jejuni and C. coli strains isolated from poultry and poultry meat. Among the strains tested, a high-level of resistance, ranging from 78% to 82% for nalidixid acid and ciprofloxacin, as well as from 44%-56% for tetracycline was observed. Moreover, all Campylobacter strains were examined for the molecular background of the appearing resistance. Almost all resistant strains tested by MAMA-PCR carried the Thr-86-to-Ile mutation in the gyrA gene. This mutation was not found in the sensitive strains. These results were confirmed by DNA sequencing performed on a group of selected strains. Moreover, all tetracycline-resistant, but none of the sensitive Campylobacter strains possessed the tet(O) gene. These data revealed that the antibiotic resistance of Campylobacter strains represent a considerable risk for the consumption of poultry meat and should be monitored in the poultry production chain.