The preferred medium for the isolation of Bordetella pertussis is

The preferred medium for the isolation of Bordetella pertussis is Bordet-Gengou medium. This medium is specifically designed for the isolation of pertussis, as it provides the nutrients necessary for the growth of this slow-growing organism while also inhibiting the growth of competing flora. Bordet-Gengou medium contains potato infusion, glycerol, and sheep blood which together support the growth of B. pertussis, allowing for its effective isolation from clinical specimens.

The other mediums listed may be suitable for various bacteria but do not offer the same specificity or nutritional support for Bordetella pertussis. Chocolate agar is enriched and supports the growth of many fastidious organisms but lacks the selective components required for B. pertussis. Charcoal-cephalexin agar can inhibit other bacteria but is not the traditional or preferred choice for isolating Bordetella pertussis. Clotted rabbit blood can support the growth of certain bacteria but is not specific for Bordetella, thus making it less suited for isolation purposes.

Using Bordet-Gengou medium is essential for obtaining reliable and accurate results when isolating Bordetella pertussis in the laboratory setting.