This project used the Qualicon Riboprinter Microbial Characterization System to characterize strains of microbial pathogens found in foods and food processing environments, study the emergence and spread of new strains (particularly antibiotic resistant strains), develop procedures for sharing molecular fingerprinting data between laboratories, and develop guidelines for the use of molecular fingerprinting technology in applications such hazard identification, risk assessment, microbial challenge studies, and HACCP validation.
At this time, we have analyzed over 1450 microbial strains, primarily isolates of Listeria monocytogenes, HUS-associated non-0157 E coli, Vibrio parahaemolyticus, and Clostridium botulinum. We have continued to expand and analyze our large collection of L. monocytogenes isolates. We are also screening all of these isolates for antibiotic resistance, as well as analyzing antibiotic resistant isolates obtained from other labs. One major goal of the Food Safety Initiative in the next year is to conduct a risk assessment for V. parahaemolyticus. We have begun to assemble a library of fingerprint patterns for V. parahaemolyticus. Our initial work has shown that Riboprinting can be used readily differentiate strains of this species. Although the O157:H7 serotype of E. coli is most frequently associated with HUS in the US, other serotypes have been associated with foodborne outbreaks in other countries. We have been able to show that Riboprinting can be used to subtype several of these serotypes, particularly O111 and O104. This work will be extended during the next year to more isolates, other serotypes, and to isolates of these serotypes associated with infantile diarrhea. One publication is in submission to a journal, one is in clearance, and one is in preparation.