TABLE 1.

Culture procedure used for investigation of fecal samples for the presence of Campylobacter spp., Salmonella enterica, Shigella spp., and E. coli O157

PathogenCulture methodIdentification method
Campylobacter spp.Preston agar (Campylobacter agar base [CM689; Oxoid] with supplement SR204E); microaerophilic environment at 42°C for 48 hTypical macroscopic and microscopic appearance; positive catalase/oxidase reactions
Salmonella enterica DCA and XLDa; incubation overnight at 37°C; enrichment overnight in Selenite broth (LP0121); subculture to Harlequin medium (Hal1; LabM)Results for suspicious colonies confirmed biochemically and serologicallyb
Shigella spp.DCA and XLD and incubated overnight at 37°CResults for suspicious colonies confirmed biochemically and serologicallyb
E. coli O157Cefixime tellurite sorbitol MacConkey agar (W11021; LIP Diagnostic Services, Galway, Ireland); incubation overnight at 37°CResults for suspicious colonies confirmed biochemically and serologicallyb
  • a DCA, desoxycholate citrate agar (CM0227; Oxoid); XLD, xylose lysine desoxycholate agar (Lab 32; LabM).

  • b The results for all suspicious isolates were confirmed by reference laboratories.