Detection of Total and Pathogenic Vibrio parahaemolyticus in Shellfish Growing along the South Yellow Sea and the East China Sea

Feng Han; Run-Run Gu; Xiao-Sheng Shen; Yuan-Ge Chen; Liang-Liang Tian; Wei-Feng Zhou; You-Qiong Cai

doi:10.4315/0362-028X.JFP-17-080

Detection of Total and Pathogenic Vibrio parahaemolyticus in Shellfish Growing along the South Yellow Sea and the East China Sea

J Food Prot. 2017 Nov 1;80(11):1882-1889. doi: 10.4315/0362-028X.JFP-17-080.

Authors

Feng Han^{1

2}, Run-Run Gu^{1

2}, Xiao-Sheng Shen^{1

2}, Yuan-Ge Chen¹, Liang-Liang Tian^{1

2}, Wei-Feng Zhou¹, You-Qiong Cai^{1

2}

Affiliations

¹ East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200090, People's Republic of China.
² Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, People's Republic of China.

PMID: 29039708
DOI: 10.4315/0362-028X.JFP-17-080

Abstract

This study was conducted to monitor the densities of total and pathogenic Vibrio parahaemolyticus in 300 samples of nine shellfish species harvested from the coasts of the South Yellow Sea and the East China Sea (N 23° to 34°, E 116° to 124°), People's Republic of China, between May and October 2015. Total V. parahaemolyticus densities were measured, and V. parahaemolyticus isolates were biochemically identified with probes for the thermostable direct hemolysin gene (tdh) and the thermostable direct hemolysin-related hemolysin gene (trh). We found that 202 of the 300 samples were positive for V. parahaemolyticus from all the sites: 58 of the 100 samples from the Fujian province, 71 of the 100 samples from the Zhejiang province, and 73 of the 100 samples from the Jiangsu province. In most (170) of the 300 samples, V. parahaemolyticus densities were 0.3 to 10 most probable number (MPN)/g; five lots exceeded 110 MPN/g, and two lots were estimated at 110 MPN/g. Among the 202 V. parahaemolyticus strains, only one was trh positive. Densities of V. parahaemolyticus in these shellfish were temperature dependent, with highest densities in June and July. Among the nine mollusk species, V. parahaemolyticus was most abundant in the agemaki clam (Sinonovacula constricta). The highest and lowest V. parahaemolyticus prevalences were found in oriental cyclina (Cyclina sinensis, 93.8%) and mussels (Mytilus edulis, 28.1%), respectively. Overall, although V. parahaemolyticus is widely distributed in marine environments, the density of V. parahaemolyticus was low and the prevalence of the main virulence factor was very low in shellfish along the coasts of the South Yellow Sea and East China Sea, which is important from a public health perspective. Data presented here will be useful for correlational research and can be utilized for developing risk management plans that establish food safety guidelines for V. parahaemolyticus in Chinese shellfish.

Keywords: Vibrio parahaemolyticus; People's Republic of China; Shellfish; Virulence gene.