Isolation of Yersinia enterocolitica Bacteriophage From Hospital Wastewater

Background: Yersiniosis is a common foodborne infection caused by Yersinia enterocolitica. This bacterium is frequently isolated from animals. Generally, bacteriophages (phages) are viruses that only infect bacteria, and are ubiquitous in the world including the intestinal tracts of animals and sewage. Today, due to the development of antibiotic resistance among bacteria, studies on phages have been considered as a controlling factor for bacterial infections. Objective: The aim of this study was to identify and isolate Y. enterocolitica, the bacterium-specific phage, from raw sewage. Materials and Methods: Every 10 minutes, 6 samples each containing 30 mL raw wastewater were collected from the sewage treatment center of Vali-asr hospital, Tehran-Iran. Bacteriophage was isolated from sewage samples using Double-Layer Agar method. In addition, the samples were purified and the volume required for the isolation of bacteriophage was determined. Then, we investigated the sensitivity of the isolated bacteriophage to the temperature. Results: Lytic bacteriophages were isolated from the samples obtained from hospital sewage. This bacteriophage was largely active on Y. enterocolitica. It was active at 4, 22, 37, 40, 50, 60, and 70°C, however it became inactive at 80°C. Conclusion: The results showed that Y. enterocolitica specific bacteriophage could be isolated from hospital sewage samples.