Publikationsdatenbank

Genetic and phenotypic characterization of Vibrio cholerae non-O1/non-O139 isolated from German retail seafood and coastal areas (2020)

Art

Vortrag

Autoren

Fleischmann, S. (WE 8)

Strauch, E.

Eichhorn, I. (WE 7)

Landoin, L.

Pickert, R.

Schille, T. B.

Alter, T. (WE 8)

Kongress

6th Joint Conference of the DGHM & VAAM

Leipzig, 08. – 11.03.2020

Quelle

6th Joint Conference of the DGHM & VAAM : 8–11 March 2020 Leipzig : Abstracts — German Society for Hygiene and Microbiology, Association for General and Applied Microbiology (Hrsg.)

Leipzig, 2020 — S. 16

Sprache

Englisch

Verweise

URL (Volltext): https://www.dghm-vaam.de/fileadmin/congress/media/dghmvaam2020/druckelemente/DGHMVAAM2020_Abstractband.pdf

Kontakt

Institut für Lebensmittelsicherheit und -hygiene

Königsweg 69
14163 Berlin
+49 30 838 62551 / 52790
lebensmittelhygiene@vetmed.fu-berlin.de / fleischhygiene@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Vibrio (V.) cholerae belonging to the non-O1/non-O139 serogroups are present in German retail seafood as well as on the German coastal areas. These bacteria can be transmitted through the contact with contaminated seawater or the consumption of contaminated water and undercooked/raw seafood causing intestinal or extraintestinal infections. At present V. cholerae infections are rare in Germany but the risk of infections increases due to the steadily rising occurrence of Vibrio species caused by global warming.

In this study, 63 V. choleraestrains isolated from German retail seafood and 35 strains isolated from coastal areas of the German North Sea and Baltic Sea were analyzed using phenotypical and genotypical methods comparing these strains to 18 clinical non-O1/non-O139 strains as well as 5pandemic O1/O139 strains to assess their pathogenic potential. Phenotypic assays were performed for hemolysin activity, human serum resistance and biofilm formation. The genetic characterization was carried out with regard to the major virulence-associated factors or markers of clinical V. cholerae, including the cholera toxin and the toxin-coregulated pilus as well as hemolysins, repeats-in-toxin toxins, pandemic islands VSP-1 /VSP-2 and the typeIII secretion system.

First results showed, that the main cholera virulence factors (ctx, zot, ace, tcpA, rstRand serogroups O1/O139) were absent in all non-O1/non-O139 V.choleraestrains. In contrast, genes encoding for the typeIII secretion system and the cholix toxin (ChxA) were present only in non-O1/non-O139 V.cholerae strains. Hemolysin genes like hlyA and dth conferring hemolysis on sheep blood agar, the resistance to human serum and the formation of biofilm were present in all groups. Additionally, a strong biofilm formation seems to be associated to non-clinical non-O1/non-O139 V. cholerae strains.

Against the background of global warming and an increasing seafood consumption in Germany (including the consumption of raw products like raw oysters and sushi), an additional testing for virulence genes beside ctx and serogrouping of O1/O139 should be considered in food diagnostics of Vibrio spp.