title: Prevalence, characterization, and antibiotic susceptibility of Vibrio parahaemolyticus isolated from retail aquatic products in North China.
abstract: BACKGROUND
  Vibrio parahaemolyticus is a major foodborne pathogen, particularly in Asian countries. Increased occurrence of outbreaks of V. parahaemolyticus gastroenteritis in China indicates the need to evaluation of the prevalence of this pathogenic species. V. parahaemolyticus distribution in shellfish from the eastern coast of China has been reported previously. However, to date, the prevalence of V. parahaemolyticus in retail aquatic products in North China has not been determined. To investigate the prevalence of V. parahaemolyticus in aquatic products in North China, 260 aquatic product samples were obtained from retail markets in 6 provinces of North China from November to December in 2012 and July to August in 2013.
  
  
  RESULTS
  V. parahaemolyticus was detected in 94 (36.2%) of the samples by the most probable number method. The density of V. parahaemolyticus ranged from 1.50 to 1100 MPN/g. V. parahaemolyticus was detected at a rate of 50.0% and 22.7% in summer and in winter, respectively. The density of V. parahaemolyticus was significantly higher in summer than in winter, with mean levels of 16.5 MPN/g and 5.0 MPN/g, respectively. Among 145 V. parahaemolyticus isolates examined, none of the isolates possessed tdh and trh. In multiplex PCR-based O-antigen serotyping of these 145 isolates, all serotypes, other than O6, O7, and O9, were detected, and serotype O2 was found to be the most prevalent (detected in 54 isolates). The 145 isolates were grouped into 7 clusters by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) at a similarity coefficient of 0.66. The antimicrobial resistance patterns of these 145 isolates to 12 antimicrobial agents revealed that most of the isolates were resistant to streptomycin (86.2%), while fewer were resistant to ampicillin (49.6%), cefazolin (43.5%), cephalothin (35.9%), and kanamycin (22.1%). All of the examined isolates were susceptible to azithromycin and chloramphenicol.
  
  
  CONCLUSIONS
  The findings of this study will help in defining appropriate monitoring programs, understanding of the dissemination of antibiotic resistant strains, and providing information for the assessment of exposure to this microorganism at the consumption level.
authors.affiliation: State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, No. 100 Central Xianlie Road, Guangzhou, 510070, China.
authors.forename: Xiaoke
authors.initials: X
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, No. 100 Central Xianlie Road, Guangzhou, 510070, China.
authors.forename: Jianheng
authors.initials: J
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, No. 100 Central Xianlie Road, Guangzhou, 510070, China. wuqp203@163.com.
authors.forename: Qingping
authors.initials: Q
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, No. 100 Central Xianlie Road, Guangzhou, 510070, China.
authors.forename: Jumei
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Institute of Microbiology, No. 100 Central Xianlie Road, Guangzhou, 510070, China.
authors.forename: Tengfei
authors.initials: T
authors.lastname: Xie
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002681:China; D024881:Drug Resistance, Bacterial; D005506:Food Contamination / Q000032:analysis / Q000706:statistics & numerical data; D012758:Shellfish / Q000191:economics / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*; D014774:Virulence
chemical_list: D000900:Anti-Bacterial Agents