[Antibiotic sensitivity of Pasteurella multocida and related bacteria (bacterial groups M5 and EF4). Studies of minimal inhibitory concentrations by agar dilution].

We have been isolating Pasteurella multocida and similar germs increasingly during the last few years: due to the rabies coming back in Eastern France, more consultations have been held following animal bites; samples are then taken for a bacteriologic research. We have studied their sensitivity towards 30 antibiotics. The determination of the MIC was achieved through the agar dilution method on 34 Pasteurella multocida of human origin issued after bites and expectorations, 4 EF4 and 4 M5. The Pasteurella are very sensitive to: beta-lactam antibiotics (the lowest MIC were observed for ureido-penicillins, amino-benzylpenicillins and third generation cephalosporins), chloramphenicol, cyclines and quinolones. Fosfomycin colistin and aminoglycosides are also active but with higher MIC. The macrolides have got a slow or no activity at all. The M5 are susceptible to the same antibiotics as Pasteurella but with slightly higher concentrations. Regarding EF4, minor sensitivity or resistance to penicillin G, cephalothin and cefamandole can be pointed out.