Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 35 5 2013 12 05 The Effect of Temperature in Invasive Properties of Yersinia Species Isolated from Human and Non-Human Sources 46 55 EN Mohammad Mahdi Soltan Dallal Roonak Bakhtiari Farzaneh Amin Harati Mohammad Kazem Sharifi Yazdi Journal Article 2013 03 14 2013 05 16 Background and Objectives: Diarrhea is one of the most important causes of children mortality in developing countries. Gastroenteritis causes mortality in children younger than five years old annually; meanwhile, Yersinia species are one of the main agents causing diarrhea. In this study the effect of temperature on invasive property of Yersinia species were investigated by using HEP-2 cell culture. Materials and Methods: In total 50 Yersinia species from French and Iranian surceases including Yersinia enterocolitica (n=30), Yersinia intermedia(n=14),Yersinia frederiksenii (n=2),Yersinia kristensenii (n=1) and Yersinia aldovae (n=1),were used. The activity of mentioned Yersinia species was determined on HEP-2 cells at 22C and 37 C, by using HEP-2 cell culture. Results: Only 10 tested Yersinia species were showed property invasive at 22C. and Yersinia enterocolitica was the most invasive strain(20%).The results showed that environmental species are also capable of causing diseases .The comparison results, of isolates from French with Iran ,showed that in general European isolates were more virulent than Iranian isolates. In addition the environmental species of Iran were not capable of causing diseases .The antibiotic susceptibility testing of isolates showed that nearly 88% of all isolates were sensitive to tested antibiotics, regardless of isolate sources Conclusion: Environmental species are capable of having invasive property which is temperature dependent.