Fate of Clostridioides difficile spores in brain heart infusion broth and selected foods

This study investigated the potential growth of Clostridioides difficile RT078 and RT126 in brain heart infusion (BHI) broth (without supplements) and in beef, chicken, cottage cheese and spinach incubated at 25°C and 37°C. Cells were enumerated on BHI agar with selective C. difficile supplements including cefoxitin, d-cycloserine and sodium taurocholate (BHIST). Growth was obtained for all ribotype-temperature combinations in BHI. Significantly higher counts, as compared to the initial concentration, were also obtained in chicken for both ribotypes at 37°C but not at 25°C. The counts achieved were 6.0 log10 cfu g-1 for RT078 and 5.8 log10 cfu g-1 for RT126, both after 4 days. Growth was not observed in beef, cottage cheese, or spinach. To the best of our knowledge this is the first time growth of C. difficile has been reported on chicken meat.