Virulence gene detection of <I>Vibrio parahaemolyticus</I> in 3 food poisoning events

ObjectiveTo isolate pathogenes from stool samples of patients and other samples collected from food-processing tools in 3 food poisoning events, and identify the type and virulence gene of pathogens isolated. MethodsSuspect pathogen was isolated and identified in accordance with National Standard GB/T 4789-2003 and GB/T 4789.7 -2008; The detected IVibrio parahaemolyticus/I was tested for species-specific gene (320 bp), thermostable direct hemolysin gene (Itdh/I 434 bp), Itdh/I-related hemolysin gen (Itrh/I 250 bp) by PCR and thermolabile hemolysin gene (Itlh/I 229 bp) by LAMP. ResultsSeven strains of IV. parahaemolyticus/I was detected in 27 samples collected from patients, cooks and processing tools in 3 food poisoning events, including 6 strains from stool samples of patients and 1 strains from samples of processing tools. The serotype of 7 isolated IV. parahaemolyticus/I strains were O10∶K66, O2∶K3, O1∶K33。 The isolates in each food poisoning events had the same biological characteristics, serotype and drug susceptibility test result and emerged Kanagawa phenomenon (KP), similar species-specific gene Vp bands were detected in Itlh/I virulence genes, but the Itdh/I, Itrh/I genes were negative. ConclusionIt was confirmed the 3 food poisoning events were caused by the pollution of different serotype IV. parahaemolyticu/I of Itlh/I+/Itdh/I-/Itrh/I-.