Surveillance and molecular characterization of vibrio parahaemolyticus from different sources in Zhoushan islands, China

V. parahaemolyticus is one of the most important foodborne pathogens in China and other countries. In this study, researchers investigated the contamination of V. parahaemolyticus in. shellfish during different seasons in Zhoushan islands. Meanwhile, researchers reported the prevalence, molecular characterization and virulence genes of V. parahaemolyticus from shellfish and clinical patients. In shellfish, the positive rate was 85, 80, 75 and 10%, respectively in different seasons from Spring to Winter. Among the shellfish isolates, there was no tdh(+) strains and only 4% trh(+) strains. The prevalence of V. parahaemolyticus in clinical samples was 36 and 77.78% of clinical strains were tdh(+), toxRS/new(+), orf8(+) and 5.56% clinical strains were trh(+). In 80% similarity, the total of 53 strains could be divided into twenty nine types. Most of the shellfish strains present various patterns with far relationship while all the pandemic strains from clinical samples belonged to same clone group with 82.8% similarity. The tdh(+), toxRS/new(+) and orf8(+) strains were the main. epidemic strains in. Zhoushan islands.