Evaluation of transport media for Campylobacter jejuni in human fecal specimens

Abstract

It is not always possible to culture feces immediately, and appropriate methods for transport of human specimens, unlike those from animals, have not been fully evaluated. Therefore, we took serial subcultures in two phases from six transport media inoculated with human diarrheal stools known to be positive for Campylobacter jejuni. In phase 1, Cary-Blair medium and buffered glycerol saline did not preserve C. jejuni as well as did alkaline peptone-water (APW), modified Cary-Blair medium, thioglycolate broth (Thio), and Campy-Thio. The four best media (APW, Cary-Blair medium, Thio, and Campy-Thio) preserved 20 fecal samples with C. jejuni better at 4°C (90% survival for 5 to 8 days) than at 25°C (90%survival for 1.7 to 2 days). In phase 2, APW and Thio, along with four modifications of the best media in phase 1, were tested with 23 positive strains. The ranges of survival times with modified media at 25°C were 1.3 to 2.2 days (90%) and 4.7 to 6.8 (50%). APW with reducing agents preserved C. jejuni better than did APW alone, Thio plus ox bile, or Campy-Thio plus ox bile (P < 0.05). Thio at pH 8.5 was better at preserving C. jejuni than was APW or Thio plus ox bile (P < 0.05). If human fecal specimens cannot be refrigerated during transport or storage, we recommend the use of Thio at pH 8.5 or APW with reducing agents for preservation of C. jejuni at 25°C.