Search results for "Vibrio Infections"
showing 10 items of 54 documents
Efficacy of a bivalent vaccine against eel diseases caused by Vibrio vulnificus after its administration by four different routes
2003
Vulnivaccine, a vaccine against vibriosis caused by Vibrio vulnificus serovar E (formerly biotype 2), confers acceptable levels of protection to eels after its administration by prolonged immersion in three doses. Recently, a new pathogenic serovar, named serovar A, has been isolated from vaccinated eels in a Spanish freshwater eel farm. The main objective of this work was to design a bivalent vaccine, and to study its effectiveness against the two pathogenic serovars. With this aim, eels weighing around 20 g were immunised with the bivalent vaccine by oral and anal intubation, intraperitoneal injection (i.p.) and prolonged immersion. The overall results indicated that: (i) the new vaccine …
Microbial and histopathological study of the vibriosis caused by Vibrio vulnificus serovar E in eels: The metalloprotease Vvp is not an essential les…
2008
Vibrio vulnificus biotype 2 serovar E (Bt2-serE) is a zoonotic pathogen that causes a haemorrhagic septicaemia in eels, called warm water vibriosis. The main objective of the present work was to study the onset of the eel vibriosis from the microbiological and histopathological viewpoint, as well as to ascertain the role of the protease Vvp as a lesional factor by comparing the histopathological lesions caused by the wild strain and its vvp deficient derivative. The wild-type strain was observed to attach to the gills, where it multiplied following saturation dynamics, subsequently invading the blood stream and reaching the internal organs. Here it reached population sizes that are notably …
Multiplex PCR Assay for Detection of Vibrio vulnificus Biotype 2 and Simultaneous Discrimination of Serovar E Strains
2007
ABSTRACT In the present work we develop a multiplex PCR assay for the detection and identification of the fish pathogen Vibrio vulnificus biotype 2 with discriminating potential for zoonotic strains (serovar E). The PCR assay allowed the identification of two new biotype 2 serovar E human isolates from culture collections. Finally, the multiplex was successfully applied to both diagnosis and carrier detection in field samples.
Protocol for Specific Isolation of Virulent Strains of Vibrio vulnificus Serovar E (Biotype 2) from Environmental Samples
2004
ABSTRACT The eel pathogen Vibrio vulnificus biotype 2 comprises at least three serovars, with serovar E being the only one involved in both epizootics of eel vibriosis and sporadic cases of human infections. The virulent strains of this serovar (VSE) have only been recovered from clinical (mainly eel tissue) sources. The main objective of this work was to design and validate a new protocol for VSE-specific isolation from environmental samples. The key element of the new protocol is the broth used for the first step (saline eel serum broth [SEB]), which contains eel serum as a nutritive and selective component. This approach takes advantage of the ability of VSE cells to grow in eel serum an…
Evidence that water transmits Vibrio vulnificus biotype 2 infections to eels
1995
Vibrio vulnificus biotype 2 is classically considered an obligate eel pathogen. However, it has recently been associated with one human septicemic case. In this paper, the opportunistic behavior of this pathogen is discussed. The bacterium can survive alone in brackish water or attached to eel surfaces for at least 14 days. It is able to spread through water and infect healthy eels by using skin as a portal of entry. These results suggest that water and infected eels may act as reservoirs of infection. A capsule seems to be essential for waterborne infectivity, which would explain why cells recovered from naturally diseased eels give rise to pure cultures of opaque colonies. The spread of t…
Phenotypic and genotypic characterization of a new fish-virulent Vibrio vulnificus serovar that lacks potential to infect humans.
2007
Vibrio vulnificus is a bacterial species that is virulent for humans and fish. Human isolates are classified into biotypes 1 and 3 (BT1 and BT3) and fish isolates into biotype 2 (BT2). However, a few human infections caused by BT2 isolates have been reported worldwide (zoonosis). These BT2 human isolates belong to serovar E (SerE), which is also present in diseased fish. The aim of the present work was to characterize a new BT2 serovar [serovar A (SerA)], which emerged in the European fish-farming industry in 2000, by means of phenotypic, serological and genetic [plasmid profiling, ribotyping and random amplified polymorphic DNA (RAPD)] methodologies. The results confirmed that SerA constit…
Identification of DNA sequences specific for Vibrio vulnificus biotype 2 strains by suppression subtractive hybridization.
2005
ABSTRACT Vibrio vulnificus can be divided into three biotypes, and only biotype 2, which is further divided into serovars, contains eel-virulent strains. We compared the genomic DNA of a biotype 2 serovar E isolate (tester) with the genomic DNAs of three biotype 1 strains by suppression subtractive hybridization and then tested the distribution of the tester-specific DNA sequences in a wide collection of bacterial strains. In this way we identified three plasmid-borne DNA sequences that were specific for biotype 2 strains irrespective of the serovar and three chromosomal DNA sequences that were specific for serovar E biotype 2 strains. These sequences have potential for use in the diagnosis…
Role of the metalloprotease Vvp and the virulence plasmid pR99 of Vibrio vulnificus serovar E in surface colonization and fish virulence.
2007
The virulence for eels of Vibrio vulnificus biotype 2 serovar E (VSE) is conferred by a plasmid that codifies ability to survive in eel serum and cause septicaemia. To find out whether the plasmid and the selected chromosomal gene vvp plays a role in the initial steps of infection, the VSE strain CECT4999, the cured strain CT218 and the Vvp-deficient mutant CT201 (obtained in this work by allelic exchange) were used in colonization and virulence experiments. The eel avirulent biotype 1 (BT1) strain YJ016, whose genome has been sequenced, was used for comparative purposes. The global results demonstrate that the plasmid does not play a significant role in surface colonization because (i) CEC…
Presence of a capsule in Vibrio vulnificus biotype 2 and its relationship to virulence for eels
1993
Strains of Vibrio vulnificus biotype 2, isolated from internal organs of diseased European eels as pure cultures of opaque cells, together with some reference strains from Japanese eels, were used in this study. Spontaneous translucent-phase variants were obtained from the corresponding parent strains and compared for a variety of phenotypic traits related to virulence for eels. The rate of colony dissociation from opaque to translucent cells was higher (around 10(-2)) than that observed for translucent to opaque cells (10(-3) to 10(-4)). Electron microscopy with ruthenium red revealed the presence of a capsule of variable thickness on opaque cells, whereas translucent-type colonies had no …
Role of mucosal immune response and histopathological study in European eel (Anguilla anguilla L.) intraperitoneal challenged by Vibrio anguillarum o…
2021
Abstract The external mucus layer that covers fish skin contains numerous immune substances scarcely studied that act as the first line of defence against a broad spectrum of pathogens. This study aimed to characterize and describe for the first time several humoral immune defence parameters in the skin mucus of the European eel (Anguilla anguilla) after intraperitoneal injection with Vibrio anguillarum or Tenacibaculum soleae. This study evaluated several immune-related enzymes and bactericidal activity against fish pathogenic bacteria in the skin mucus of European eels at 24, 48, and 72 h post-challenge. The results demonstrated that European eel skin mucus showed significant increments i…