Antibiotic susceptibilities of Listeria: in vitro studies.

Although Listeria is a rather susceptible bacterium, most antibiotics exert a bacteriostatic effect on Listeria monocytogenes. Except for fosfomycin, antibiotic susceptibilities are similar among the species of the genus Listeria. In vitro, bactericidal effect is often achieved by the use of antibiotic combinations. The most commonly used combinations are ampicillin with aminoglycosides. Up until now, there has been no trend towards reduced susceptibility of Listeria to antibiotics.