ABSTRACT
Cronobacter are a group of opportunistic pathogens that cause life-threatening infections in individuals of all ages. The genus Cronobacter includes Cronobacter sakazakii, Cronobacter malonaticus, Cronobacter muytjensii, Cronobacter turicensis, Cronobacter dublinensis, Cronobacter universalis, and Cronobacter condimenti. Of the seven species, the primary pathogens are C. sakazakii, C. malonaticus, and C. turicensis. Epidemiologically, intrinsically and extrinsically contaminated powdered infant formula (PIF) and expressed breast milk have been noted sources of infantile infections. However, definitive sources for adult infections have been more elusive. These organisms are highly resistant to osmotic, thermal, and oxidative stress and can persist for long periods of time within PIF manufacturing facilities. Several virulence factors are encoded on a variety of mobile genetic elements such as plasmids. This genomic plasticity suggests that ongoing re-assortment and possibly acquisition of future virulence factors will undoubtedly complicate efforts to categorize these organisms into sharply demarcated genomo-pathotypes. Whole genome sequencing is a powerful tool in foodborne investigations which accurately captures subtle genomic differences in strains belonging to similar sequence types or ecological niches and is useful for source attribution and traceback investigations. Recent findings of multidrug antibiotic resistance among Cronobacter suggests that the global food safety community continue its current surveillance activities.
