Method for the isolation and detection of Enterobacter sakazakii (Cronobacter) from powdered infant formula

In the United States, there are approximately 76 million foodborne cases annually. Although the number of food-related infections caused by Enterobacter sakazakii is relatively low, the United States Food and Drug Administration in 2002 became concerned about the incidence of E. sakazakii infections related to powdered infant formula (PIF). At that time, a method to isolate this pathogen from PIF was developed and implemented in several cases. This protocol requires multiple steps and up to 7 days to complete. Recently, a new method was developed that incorporates a real-time PCR-based assay and chromogenic agars to improve isolating and detecting this pathogen in PIF. The updated protocol has undergone and successfully concluded an AOAC pre-collaborative study and is in the process of further validation for the inclusion into the FDA's Bacteriological Analytical Manual. This manuscript describes the performance evaluation of the new method.