Objective: To understand the genetic polymorphism of Salmonella and Staphylococcus aureus in Guangdong province, as well as to explore methods for identifying and tracing the source of these two foodborne pathogens.
Methods: Using the automated ribotyping system, two foodborne pathogens were tested with either EcoR I or Pvu II restriction enzymes. BioNumerics software was then applied for image analysis, database establishment and other corresponding analysis.
Results: Digestion of 32 Salmonella isolates with Pvu II yielded 19 different ribotypes, and digestion of 14 Salmonella isolates with EcoR I yielded 2 different ribotypes. Staphylococcus aureus isolates showed greater genetic diversity, whereas EcoR I digestion of 49 different isolates yielded 31 different ribotypes.
Conclusion: Unique Salmonella and Staphylococcus aureus isolates could be identified through ribotyping. Although Salmonella serotyping and ribotyping were not strongly correlated, the combination of both restriction enzymes could be used to more effectively identify the genetic relationship among different strains as well as the source of food poisoning. Thus, not only could the genetic relationships amongst the different strains be inferred through ribotyping skills, the source of food poisoning and mode of transmission could also be determined under the use of this method.