[Molecular typing on Vibrio parahaemolyticus isolates from Hangzhou, China, during 2000-2002].
OBJECTIVE
To study the molecular epidemiology of Vibrio parahaemolyticus isolates from clinical and environmental samples collected in Hangzhou area during 2000 and 2002.


METHODS
V. parahaemolyticus isolates from food-poisoning, sporadic diarrhea patients and seafood in market in Hangzhou during 2000 and 2002 were serotyped. From clinical isolates of serotype O3:K6 and environmental isolates of serotype O3:KUT, virulence genes, tdh and trh, were examined by PCR. Molecular typings [including ribotyping, random amplified polymorphic DNA analysis (RAPD), enterobacterial repetitive intergenic consensus PCR (ERIC-PCR)], were also performed.


RESULTS
Among 13 food-poisoning outbreaks caused by V. parahaemolyticus, O3:K6 strains with tdh positive and trh negative were detected in 11 episodes (84.6%), and O4:K8 strains with tdh positive and trh negative were responsible for other 2 outbreaks (15.4%). In 34 V. parahaemolyticus isolates from sporadic diarrhea patients, O3:K6, O4:K8, and O1:KUT strains with tdh positive and trh negative were detected with proportions of 26.5% (9/34), 17.6% (6/34), and 38.2% (13/34), respectively, and other 6 strains were not able to be serotyped. Of 64 isolates from seafood in which both tdh and trh were negative except trh was positive in one O1:KUT strain, 37 belonged to 7 serotypes except O3:K6 or O4:K8, and 9 were not able to be serotyped. The fingprintings of ribotyping, ERIC-PCR, and RAPD showed that almost all of O3:K6 isolates from food-poisoning and sporadic diarrhea patients were genetically close to each other and there were obviously genetical difference between O3:K6 isolates from clinic and O3:KUT isolates from environment.


CONCLUSIONS
There was a distinct serotype distribution between V. parahaemolyticus isolates from clinic patients and seafood. One group of close related V. parahaemolyticus O3:K6 strains with tdh positive and trh negative seemed to be prevailing in Hangzhou in those years.
Zhang
Wei
W
Hangzhou Center for Disease Control and Prevention, Hangzhou 310006, China.
Pan
Jin-cao
JC
Meng
Dong-mei
DM
Chen
Kun
K
D002681:China / Q000453:epidemiology; D004269:DNA, Bacterial / Q000032:analysis; D004196:Disease Outbreaks; D005506:Food Contamination; D005517:Foodborne Diseases; D006801:Humans; D017720:Molecular Epidemiology; D016133:Polymerase Chain Reaction; D017747:Seafood; D014736:Vibrio parahaemolyticus / Q000235:genetics* / Q000302:isolation & purification
D004269:DNA, Bacterial