Virulence Characteristics of Yersinia enterocolitica Isolated from Dairy Products in the Northeast of Iran

Yersinia enterocolitica (Y. enterocolitica) has a wide range of clinical, animal, food, and water sources, which have been documented in the literature [1-3]. In general, the genus Yersinia consists of 18 species, 11 of which have been established, including Y. pestis, Y. pseudotuberculosis, Y. enterocolitica, Y. frederiksenii, Y. intermedia, Y. kristensenii, Y. bercovieri, Y. mollaretii, Y. rohdei, Y. aldovae, and Y. ruckeri. Only the three species of Y. Pestis, Y. enterocolitica, and Y. pseudotuberculosis are considered to be pathogenic for humans and animals [1]. According to a recent report by the European Food Safety Authority (EFSA), Y. enterocolitica is considered to be an important foodborne pathogen in Europe [4]. Y. enterocolitica causes various human infections, including acute gastroenteritis and invasive syndromes such as mesenteric lymphadenitis, appendicitis, and septicemia [2, 4-6]. Y. enterocolitica is classified into six biotypes of 1A, 1B, 2, 3, 4, and 5, while it also has more than 70 different serotypes [1,7]. Based on their pathogenicity, Y. enterocolitica biotypes are classified as non-pathogenic biotype 1A and pathogenic biotypes of 1B, 2, 3, 4, and 5 [2, 6, 8]. Virulence in Y. enterocolitica could be categorized into two important structures, one of which is inside the chromosome and the other is on the plasmid of the Yersinia virulence (pYV) with the size of 64-75 kb [7]. All the six biotypes of Y. enterocolitica are able to attack the intestinal mucosa, while with only one plasmid, they could migrate to the digestive tract and internal organs [1, 2]. Biotype 1A strains are found in a wide range of environmental sources, such as soil, food, water, and sewage [3]. Journal of Human, Environment, and Health Promotion