Vibrio vulnificus and Vibrio parahaemolyticus are ubiquitous Gram-negative bacterial pathogens found naturally in marine and estuarine waters, and are a leading cause of seafood-associated bacterial illness. These pathogens are commonly reported in the USA and in many Asian countries, including China, Japan and Taiwan; however, there is growing concern that V. vulnificus and V. parahaemolyticus may represent an important and increasing clinical problem in Europe. Several factors underlie the need for a greater understanding of these non-cholera vibrios within a European context. First, there is a growing body of evidence to suggest that V. vulnificus and V. parahaemolyticus infections are increasing, and tend to follow regional climatic trends, with outbreaks typically following episodes of unusually warm weather. Such findings are especially alarming given current predictions regarding warming of marine waters as a result of global climatic change. Second, a myriad of epidemiological factors may greatly increase the incidence as well as clinical burden of these pathogens - including increasing global consumption and trade of seafood produce coupled to an increase in the number of susceptible individuals consuming seafood produce. Finally, there is currently a lack of detailed surveillance information regarding non-cholerae Vibrio infections in Europe, as these pathogens are not notifiable in many countries, which probably masks the true clinical burden of many human infections. This review will present a pertinent overview of both the environmental occurrence and clinical impact of V. vulnificus and V. parahaemolyticus in Europe.

The distribution of the concentration of potential indicators of fecal viral pollution in shellfish was analyzed under diverse conditions over 18 months in diverse geographical areas. These microorganisms have been evaluated in relation to contamination by human viral pathogens detected in parallel in the analyzed shellfish samples. Thus, significant shellfish-growing areas from diverse countries in the north and south of Europe (Greece, Spain, Sweden, and the United Kingdom) were defined and studied by analyzing different physicochemical parameters in the water and the levels of Escherichia coli, F-specific RNA bacteriophages, and phages infecting Bacteroides fragilis strain RYC2056 in the shellfish produced, before and after depuration treatments. A total of 475 shellfish samples were studied, and the results were statistically analyzed. According to statistical analysis, the presence of human viruses seems to be related to the presence of all potential indicators in the heavily contaminated areas, where E. coli would probably be suitable as a fecal indicator. The F-RNA phages, which are present in higher numbers in Northern Europe, seem to be significantly related to the presence of viral contamination in shellfish, with a very weak predictive value for hepatitis A virus, human adenovirus, and enterovirus and a stronger one for Norwalk-like virus. However, it is important to note that shellfish produced in A or clean B areas can sporadically contain human viruses even in the absence of E. coli or F-RNA phages. The data presented here will be useful in defining microbiological parameters for improving the sanitary control of shellfish consumed raw or barely cooked.

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Vibrio vulnificus is a Gram-negative bacterial pathogen responsible for the vast majority of bacterially mediated fatalities from the consumption of raw or undercooked seafood in the USA. Vibrio vulnificus-associated septicaemia can occur rapidly (< 24 h); however, methods for the isolation and confirmation of V. vulnificus from seafood samples typically require several days. A real-time PCR assay was developed for V. vulnificus biotype 1 that provides a rapid means of identifying a gene fragment (vcgC) previously indicated as a strong predictor of potential virulence. PCR probe specificity was confirmed by amplification of 17 clinical V. vulnificus strains and by the lack of amplification with seven non-pathogenic V. vulnificus isolates and a wide range of closely related bacteria. Oyster and seawater samples were amended with a range of environmentally realistic concentrations of C-genotype V. vulnificus cells, which were quantitatively and unambiguously identified according to biotype. Of some significance, we utilized a sample processing and nucleic acid extraction procedure that allowed identification of pathogenic strains of V. vulnificus from oyster matrices without prior enrichment or culturing of strains. This outlined approach allowed the detection of as little as 50 cfu of V. vulnificus in less than 5 h, which compares favourably with culture-based approaches. The results indicate the applicability of this approach for monitoring purposes or as a potential diagnostic tool in clinical settings.

Rainbow trout (Oncorhynchus mykiss) fry and fingerlings with clinical signs of rainbow trout fry syndrome, and rainbow trout (0.5 to 3.5 g) with experimentally induced infections with Flavobacterium psychrophilum, were examined histopathologically and electron microscopically. Severe hypertrophy of the spleen and cellular degeneration were consistently observed. Distinctive features of the disease were the loss of definition of the splenic border and its replacement by a loosely structured eosinophilic layer, fibrinous inflammation and intercellular oedema within the spleen, and the presence of numerous filamentous bacteria interspersed throughout the organ.