P-046. Genotyping of Cronobacter species from Infant Formula Production Environments

C. Iversen1, A. Lehner1, C. Feer2, K. Gschwend2, R. Stephan1;
1Inst. for Food Safety and Hygiene, Univ. Zurich, Zurich, SWITZERLAND, 2Hochdorf Nutritec AG, Hochdorf, SWITZERLAND.

Background: Cronobacter (a.k.a. Enterobacter sakazakii) has been associated with rare cases of meningitis, bacteremia and necrotizing enterocolitis in neonates. Infant formula has been identified as a possible route of ingestion and therefore manufacturers are keen to address this potential hazard within production facilities. Cronobacter spp. have been found in various foods, factories and home environments and appear to be normally innocuous ubiquitous organisms. However a clear contamination route for infant formula has not been established. In this study factory sites were surveyed for the presence and distribution of Cronobacter species. Methods: Samples were taken from 322 finished products, 146 ingredients and 482 various factory environments. Isolated Cronobacter spp. were genotyped using both PFGE and RAPD techniques and similarities between isolates from different locations and sample types were assessed. Results: Cronobacter were isolated from 7 end products, 16 ingredients and 47 environmental samples. The greatest diversity of PFGE pulsotypes occurred among the environmental and ingredient isolates, while a limited number of pulsotypes appeared to be responsible for end product contamination. The RAPD profiles were less discriminatory than PFGE patterns, however they allowed speciation of the Cronobacter strains. Examples of all recently proposed Cronobacter species were found during this study. Conclusion: Cronobacter spp. are ubiquitous organisms found in factory environments and dried food materials. Certain strains of Cronobacter may have properties that allow them to persist more than others in factories and intermittently contaminate food products.