Which media is primarily used for the recovery of fecal pathogens?

The identification of fecal pathogens often relies on selective media that can suppress non-pathogenic flora and support the growth of harmful organisms. Hektoen and MacConkey agars are designed specifically for this purpose.

Hektoen agar is valuable for differentiating enteric bacteria, particularly Salmonella and Shigella, from other Gram-negative bacteria found in fecal samples. It is selective due to its bile salts and dyes, which inhibit the growth of certain Gram-positive bacteria while allowing enteric pathogens to thrive.

MacConkey agar also serves a dual role; it is both selective and differential for Gram-negative bacteria. It contains bile salts and crystal violet, which inhibit Gram-positive bacteria. The lactose present in MacConkey agar allows for differentiation, as it supports the growth of lactose fermenters, while non-fermenters can be identified by their lack of color change on the medium.

Together, these media are particularly suitable for recovering fecal pathogens from samples, making this choice the most appropriate for the question posed.