Background: Yersinia enterocolitica (Y. enterocolitica) has a wide range of clinical, animal, food, and water sources. Most studies have indicated that food is the most common source of this organism. The present study aimed to evaluate the virulent genes of Y. enterocolitica isolated from dairy products in Iran. Methods: The virulence of Y. enterocolitica biotypes was investigated, which was isolated from 38 cheese and 33 raw milk samples in the northeast of Iran. In total, six virulence-related genes were evaluated, including ail, inv, yadA, myfA, ystA, and ystB in 1A, 1B, and 5 Y. enterocolitica biotypes. Results: In the isolates of the 1A biotype, ystB was the most frequent gene (86.95% and 38.46% in cheese and raw milk, respectively). In the 1B biotype, the most frequently isolated gene was yadA (92.30% and 66.66% in cheese and raw milk, respectively). In all the isolates, the least frequently isolated gene was ail, followed by myfA. Conclusion: According to the results, the presence of virulence genes in the Y. enterocolitica strains isolated from dairy products suggested that these strains could pose significant risk to public health if dispersed in susceptible human population.

Keywords