title: Temporal and Spatial Variation in the Abundance of Total and Pathogenic Vibrio parahaemolyticus in Shellfish in China.
abstract: We investigated the abundance of total and pathogenic Vibrio parahaemolyticus in shellfish sampled from four provinces in China during May 2013 and March 2014 using the most probable number-polymerase chain reaction (MPN-PCR) method. Total V. parahaemolyticus was detected in 67.7% of 496 samples. A total of 38.1% and 10.1% of samples exceeded 1,000 MPN g(-1) and 10,000 MPN g(-1), respectively. V. parahaemolyticus densities followed a seasonal and geographical trend, with Guangxi and Sichuan shellfish possessing total V. parahaemolyticus levels that were 100-fold higher than those of the Liaoning and Shandong regions. Moreover, the levels of V. parahaemolyticus were at least 10-fold higher in the summer and autumn than in the cooler seasons. Pathogenic V. parahaemolyticus levels were generally lower than total V. parahaemolyticus levels by several log units and tended to be high in samples contaminated with high total V. parahaemolyticus levels. The aqua farms had a lower prevalence but higher abundance of total V. parahaemolyticus compared to retail markets. The catering markets showed the lowest levels of total V. parahaemolyticus, but 20.0% of samples exceeded 1,000 MPN g(-1). The levels of both total and pathogenic V. parahaemolyticus in oysters were higher than in clams. The log-transformed abundance of V. parahaemolyticus was significantly correlated with both water temperature and air temperature but not water salinity. These results provide baseline contamination data of V. parahaemolyticus in shellfish in China, which can be applied to local risk assessments to prioritize risk control to key sectors and evaluate the effectiveness of future control measures.
authors.affiliation: National Institute for Nutrition and Health, Chinese Center for Disease Control and Prevention, Beijing, China; Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Haihong
authors.initials: H
authors.lastname: Han
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Fengqin
authors.initials: F
authors.lastname: Li
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Weixing
authors.initials: W
authors.lastname: Yan
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Yunchang
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Li
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Xiumei
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Jianghui
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Xu
authors.affiliation: Key Laboratory of Food Safety Risk Assessment of Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Institute of Microbiological Examination, Guangxi Regional Center for Disease Control and Prevention, Nanning, China.
authors.forename: Xiugui
authors.initials: X
authors.lastname: Li
authors.affiliation: Institute of Microbiological Examination, Sichuan Provincial Center for Disease Control and Prevention, Chengdu, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lv
authors.affiliation: Faculty of Sciences, University of Waterloo, Waterloo, Canada.
authors.forename: Yiqian
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Testing, Dalian Xigang District Center for Disease Control and Prevention, Dalian, China.
authors.forename: Te
authors.initials: T
authors.lastname: Cai
authors.affiliation: Institute of Bacterial Infectious Disease Control, Shandong Provincial Center for Disease Control and Prevention, Jinan, China.
authors.forename: Yuzhen
authors.initials: Y
authors.lastname: Chen
mesh_terms: D018533:Biomass; D002681:China; D012621:Seasons; D012758:Shellfish / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000302:isolation & purification* / Q000472:pathogenicity