Survival characteristics of Cronobacter spp. in model bovine gut and in the environment.

Cronobacter spp. (formally Enterobacter sakazakii) have been linked to illness in infants from contaminated powdered infant formula. The source of the pathogen remains unclear, and it is believed that farm environments and cattle could play a role in the transmission of Cronobacter spp. The aim of this study was to establish if the organism would survive passage through a model of the bovine rumen and abomasum and in bovine feces in the farm environment. Models of the bovine abomasum and rumen were inoculated with Cronobacter strains (final concentrations of 5.7 and 6.5 log(10) CFU/mL, respectively), and survival was examined over time in these environments using an adapted ISO/DTS 22964 culture protocol. Fecal samples were inoculated with Cronobacter (final concentration 6.0 log(10) CFU/mL), and survival on soil and in containers stored outdoors was examined over time. The results showed no significant changes in the number of Cronobacter in rumen fluid over a 24-h period. Cronobacter were undetectable after 30 min of incubation in the model abomasum. The pathogen survived 105 days in sealed containers and was detectable after 112 days in soil. This study indicated that Cronobacter spp. are unlikely to be shed in bovine feces as supported by previous surveillance studies; however, the study did show that the organism survives well in the farm environment.