Pathogenic Vibrio Species in Dutch Shellfish Destined for Direct Human Consumption

• Published in: Journal of food protection 2010-04, Vol.73 (4), p.734-738
• Main Authors: SCHETS, Franciska M, VAN DEN BERG, Harold H. J. L, RUTJES, Saskia A, DE RODA HUSMAN, Ana Maria
• Format: Article
• Language: English
• Subjects: Animals; Bacteria; Biological and medical sciences; Colony Count, Microbial; Consumer Product Safety; Crassostrea - microbiology; Fish; Fish and seafood industries; Food contamination & poisoning; Food Contamination - analysis; Food industries; Food Microbiology; Food safety; Fundamental and applied biological sciences. Psychology; Gastroenteritis; Gastrointestinal diseases; Humans; Infections; Maximum likelihood method; Mollusks; Mytilus edulis - microbiology; Netherlands - epidemiology; Oysters; Pathogens; Prevalence; Seasons; Shellfish; Shellfish - microbiology; Temperature; Vibrio alginolyticus - isolation & purification; Vibrio alginolyticus - pathogenicity; Vibrio parahaemolyticus - isolation & purification; Vibrio parahaemolyticus - pathogenicity; Water analysis; Water sampling; Water temperature
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-73.4.734

Vibrio parahaemolyticus is a common cause of shellfish-related gastroenteritis all over the world. V. parahaemolyticus and Vibrio alginolyticus have previously been detected in water samples from the Oosterschelde, a large inlet on the North Sea, which is used for both recreational purposes and shellfish production. In 2006, oysters (Crassostrea gigas) from a noncommercial oyster bed in the Oosterschelde and oysters bought in Dutch fish shops were tested for the presence of pathogenic Vibrio species; in 2007 and 2008, oysters (C. gigas) and mussels (Mytilus edulis) from Oosterschelde production areas were examined. Total Vibrio numbers were related to water temperatures to study joint patterns. Vibrio was found in oysters and mussels from the production areas, and levels ranged from 6 to 622 most probable number (MPN) per g in oysters and 6 to 62 MPN/g in mussels. Vibrio levels in oysters from fish shops were 231 to >333 MPN/g, whereas levels in noncommercial oysters ranged from 231 to >2,398 MPN/g. About 80% of the isolated strains were V. alginolyticus, and approximately 10% were identified as V. parahaemolyticus. Vibrio counts in shellfish samples increased with increasing water temperature and declined when water temperatures dropped; Vibrio was not detected when water temperatures declined to 10(4) cells per serving of oysters) required for infection, it is concluded that the risk of gastrointestinal infections with V. parahaemolyticus through consumption of shellfish from the Oosterschelde production sites is presumably low.