| Vibrio parahaemolyticus (Vibrio parahaemolyticus, VP), is a gram-negative halophilic bacteria of Vibrionaceae, membership of Vibrio pathogens, is a zoonotic pathogen, can cause diarrhea, intestinal cramps, vomiting and have a fever, typical gastroenteritis reactions and septicemia, and even death. In recent years, with the raw food and half fresh seafood consumption has increased rapidly, The potential risk of Vibrio parahaemolyticus in food is also growing. National Foodborne Disease Active Surveillance Network data show that, since1998, the distribution of the significant changes of microbial food poisoning pathogens, food poisoning caused by Vibrio parahaemolyticus, already the highest in the microbial food poisoning. Vibrio parahaemolyticus encompasses a diversity of strains with varying pathogenic potential. While many Vibrio parahaemolyticus strains could be high pathogenieity, others are a little virulent. Understand the different sources of Vibrio parahaemolyticus virulence genes carrying case, combined with the serotype and drug resistance of the correlation analysis of Vibrio parahaemolyticus in aquatic products with clinical isolates, Provide a theoretical basis for the risk assessment of Vibrio parahaemolyticus in aquatic products and carry out food safety testing.This paper isolated and identified Vibrio parahaemolyticus from323samples.323random samples from6sorts of fish, shrimp, shellfish, head race, crabs, snails and other aquatic food samples collected from supermarkets, farmers’markets, hotels (hotels), canteens. Vibrio parahaemolyticus of35strains aquatic products and14strains clinical isolated were subjected to PCR assay for two virulence-associated genes (tdh, trh) and drug resistance, to analyze the relationship between virulence-associated genes and resistant, To set up a method of evaluating the virulence of VP isolates by PCR amplification. The results:The total detectable rate of Vibrio parahaemolyticus was10.84%, The results showed that the detectable rate of Vibrio parahaemolyticus was lower than other areas. The study on the distributing status of Vibrio parahaemolyticus indicated that the able rate of Vibrio parahaemolyticus in shrimp samples was the highest (17.58%). The next was fish protucts (14.18%) and crabs products (10.00%), snails were not detected.35food isolates tdh gene carrying rate of14.29%, trh gene carrying rate was2.86%, the serum agglutination divided into eight serogroups mainly03,05,01serogroup; tdh genes of14clinical isolates cany rate of71.43%, the trh gene carrying rate of14.29%, serum agglutination divided into four serogroups, mainly concentrated in the03,04serogroup. Two different sources of Vibrio parahaemolyticus of ampicillin have strong resistance; cefotaxime, ciprofloxacin, norfloxacin sensitive; amikacin and streptomycin resistance tends neutral.The conclusions are as follows:1-. In terms of detection rate and probability, CHROMagar selective medium is better and more suitable for lab use. TCBS medium is not conducive to to distinguish Vibrio parahaemolyticus and Vibrio mimicus, Vibrio vulnificus and other marine vibrio.2> The population distribution of Vibrio parahaemolyticus is not the same in different kinds of food samples. Fish, shrimp, crab, shellfish and aquatic products were polluted by two and above vibrio and one of them was Vibrio parahaemolyticus.The results show that there is potential risk of Vibrio parahaemolyticus food poisoning in Chongqing City.3> Food isolates with clinical isolates of virulence gene carrying rate has a significant difference, but two different sources of resistance spectrum of Vibrio parahaemolyticus consistent; carry virulence genes tdh strains serotypes focused in the O3group and O1group.Suggestions:The knock-out mutants of virulence-associated genes are needed to build Vibrio parahaemolyticus pathogenic research system, to further determine the virulence traits and resistance, serotype correlation, monitoring of Vibrio parahaemolyticus food poisoning outbreak of detectionand provide the basis for tracking pollution sources. |
