Abstract
MICs and MBCs of four new macrolides (azithromycin, clarithromycin, dirithromycin and roxithromycin) and two older macrolides (erythromycin and josamycin) forBordetella pertussis andBordetella parapertussis were determined. The activity of the new macrolides was as good as that of erythromycin, while josamycin was slightly less active.Bordetella parapertussis was more resistant thanBordetella pertussis.