Shelf life of prepared Bordet-Gengou and Regan-Lowe agar plates for isolation of Bordetella pertussis.

The shelf life of prepared agar plates used for the isolation of Bordetella pertussis was studied. They contained Bordet-Gengou agar, Bordet-Gengou agar with cephalexin, Regan-Lowe agar, Regan-Lowe agar with cephalexin, or Regan-Lowe agar with both cephalexin and amphotericin B. Plates stored were compared to freshly prepared control plates for up to a maximum of 18 weeks. They were inoculated with clinical isolates of Bordetella pertussis, either in pure culture, or mixed with a defined oropharyngeal flora. Bordet-Gengou agar plates may be used, with proper storage at 4 degrees C in airtight-sealed plastic bags, for up to 10 weeks, Regan-Lowe agar plates for up to 14 weeks. Field studies are needed to substantiate our findings.