Prevalence of foodborne pathogens isolated from retail freshwater fish and shellfish in China

In 2016, the nationwide food safety surveillance was conducted on fresh water fish and shellfish in China. The prevalence of Vibrio parahaemolyticus, Vibrio cholerae, Salmonella, and L. monocytogenes were 19.0% (613/3226), 3.4% (110/3226), 3.8% (124/3226), and 2.5% (80/3226), respectively. The tdh and trh genes were detected in 19 (2.6%) and 24 (3.3%) of the 718 V. parahaemolyticus isolates, respectively. All V. cholerae strains were confirmed as non-O1/O139 serogroups. The most predominant Salmonella serotypes were S. Stanley, S. Thompson, S. Litchfield, S. Typhimurium, S. Virchow, S. Carrau, and S. Infantis. The results of this comprehensive survey showed contamination by four pathogens in fresh water fish and shellfish in China for the first time. The study indicated a need for proper handling, storage, and cooking of freshwater fish and shellfish. Further risk reduction assessment and implementation are necessary to reduce foodborne disease in China.