The comparative in-vitro activity of twelve 4-quinolone antimicrobials against Haemophilus ducreyi.

We have compared the in-vitro activity of 12 quinolone antibiotics against 50 recent isolates of Haemophilus ducreyi from The Gambia. While these isolates were relatively resistant to the parent compounds, the newly synthesized quinolones exerted significant activity against H. ducreyi. Ciprofloxacin and ofloxacin were the most active compounds (MIC90 0.03 mg/l).