Environmental occurrence and clinical impact of Vibrio vulnificus and Vibrio parahaemolyticus: a European perspective

Abstract

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.

Temporal and Spatial Distribution Patterns of Potentially Pathogenic Vibrio spp. at Recreational Beaches of the German North Sea

“…The test statistic D 2 describes the overall model performance and is given in the upper left corner of each sub-plot trh gene, but not for tdh. Comparisons with other studies show that generally between 3 and 5 % of environmental V. parahaemolyticus isolates bear either of the two virulence gene markers [67,68]. This suggests that the ratio observed here is realistic, although more strains need to be checked for more reliable evidence.…”

“…Presence of the trh gene alone seems to be a common characteristic of V. parahaemolyticus communities in Northern European waters and has been shown for several studies in this region [39,69,70]. Up to now, only tdh-positive strains were associated with V. parahaemolyticus infections in Europe, however [68], and tdh is the gene that has been mainly attributed to haemolysis [71]. Despite this, two strains that were identified as being tdhand trh-negative exhibited haemolytic capacity in the Kanagawa test.…”

Ecological determinants of the occurrence and dynamics of Vibrio parahaemolyticus in offshore areas

“…The displacement of the density fronts towards the interior of the rias during downwelling periods may represent an important supply of oceanic zooplankton and a parallel source of V. parahaemolyticus populations attached to the zooplankton. Coincidentally, one of the largest V. parahaemolyticus outbreaks detected in Europe occurred in Galicia in 1999(Lozano-Leon et al, 2003 and was concurrent with the incursion in the rias of warm tropical waters and the presence of large patches of zooplankton (Baker-Austin et al, 2010). Similar oceanographic conditions have been observed to be related to large outbreaks of V. parahaemolyticus in Peru (Martinez-Urtaza et al, V. parahaemolyticus counts were observed in the present study to increase in parallel to increased zooplankton density, measured as the number of individuals per cubic metre of water.…”

“…In recent years, increasing evidence has related major epidemic outbreaks of V. parahaemolyticus to the incursion of oceanic waters of subtropical origin in coastal areas. The emergence and spread of infections in Peru, Spain, Chile and Alaska occurred concurrently with the arrival and movement of warm oceanic waters along the coast (MartinezUrtaza et al, 2008a(MartinezUrtaza et al, , 2010Ansede-Bermejo et al, 2010;Baker-Austin et al, 2010), and with an increase in the occurrence of atypical warm-water zooplankton (Baker-Austin et al, 2010;MartinezUrtaza et al, 2010). The existence of a mechanism for the oceanic migration of V. parahaemolyticus populations implies that V. parahaemolyticus can persist in the open sea long enough to allow transport across the oceans under adverse ecological conditions for the presence of these bacteria.…”

Dangerous hitchhikers? Evidence for potentially pathogenic Vibrio spp. on microplastic particles

“…Prior studies reported that the number of Vibrio infections correspond closely with the sea surface temperature pointing to a possible link to climate change related phenomena (e.g. global warming, heat waves) (Baker-Austin et al, 2010. Böer et al (2013) reported that Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus and V. cholerae occurred in water and sediments in the central Wadden Sea and in the estuaries of the rivers Ems and Weser.…”