We have tested the in vitro activities of eight fluoroquinolones against 16
0 Brucella melitensis strains. The most active was sitafloxacin (MIC at whi
ch 90% of the isolates are inhibited [MIC90], 0.12 mu g/ml). In decreasing
order, the activities (MIC(90)s) of the rest of the tested fluoroquinolones
were as follows: levofloxacin, 0.5 mu g/ml; ciprofloxacin, trovafloxacin,
and moxifloxacin, 1 mu g/ml; and ofloxacin, grepafloxacin. and gatifloxacin
, 2 mu g/ml.