Killing of Streptococcus pneumoniae by azithromycin, clarithromycin, erythromycin, telithromycin and gemifloxacin using drug minimum inhibitory concentrations and mutant prevention concentrations

Highlights • Streptococcus pneumoniae strains are not readily killed by the measured drug minimum inhibitory concentration (MIC). • S. pneumoniae are killed by the drug mutant prevention concentration (MPC) over a wide bacterial density range. • Fast bacterial killing may reduce the likelihood for resistance selection. • The traditional definition of bactericidal and bacteriostatic may be too limited.