Etiological analysis of Vibrio parahaemolyticus in Xuzhou city in Jiangsu province,2009

Objective To investigate the etiological characteristics of Vibrio parahaemolyticus (VP) in Xuzhou. Methods VP was detected in the samples collected according to GB/T 4789.7, the serotyping of isolated VP strains was conducted, drug susceptibility test was performed for these isolates and virulence genes of tdh and trh were detected by using PCR. Results Twenty three VP strains were detected in 40 aquatic products (57.50%), 2 of them were trh gene positive. Of 23 VP strains, 3 were not specified in serotype, the others belonged to 7 serotypes (O1, 2, 3, 4, 5, 10, 11), and serotypes O1,O4 and O5 predominated, accounting for 65.22% (15/23). The detection rate of VP in stool samples of diarrhea patients was 8.00% (4/50), and 2 of the strains were identified as serotype O3:K6 and tdh gene positive. The positive rate of trh gene in the VP in aquatic products was 8.70% (2/23), but no tdh gene was detected. The positive rate of tdh gene in the stool samples of diarrhea patients was 50.00%, but no trh gene was detected. The VP strains from aquatic products were resistant to ticarcillin, amoxicillin, tobramycin, cefuroxime and cefoxitin. The strains from the stool samples of diarrhea patients were resistant to ticarcillin, amoxicillin. Conclusion The carriage rate of VP in aquatic products was high in Xuzhou, and VP strains with virulence genes were isolated from the stool samples of diarrhea patients. The resistance of VP to antibiotics was serious. The difference on clinical symptoms in patients caused by the infection of VP with different etiology characteristics was not obvious. The surveillance in serotype, drug resistance and virulence gene carriage should be strengthened, and the research on the relationship between diarrhea patients' clinical symptoms and etiological features of VP should be continued.