Prevalence Of Vibrio Research Articles

Multidrug-Resistance of Vibrio Species in Bivalve Mollusks from Southern Thailand: Isolation, Identification, Pathogenicity, and Their Sensitivity toward Chitooligosaccharide-Epigallocatechin-3-Gallate Conjugate.

Vibrio spp. is a Gram-negative bacteria known for its ability to cause foodborne infection in association with eating raw or undercooked seafood. The majority of these foodborne illnesses are caused by mollusks, especially bivalves. Thus, the prevalence of Vibrio spp. in blood clams (Tegillarca granosa), baby clams (Paphia undulata), and Asian green mussels (Perna viridis) from South Thailand was determined. A total of 649 Vibrio spp. isolates were subjected to pathogenicity analysis on blood agar plates, among which 21 isolates from blood clams (15 isolates), baby clams (2 isolates), and green mussels (4 isolates) showed positive β-hemolysis. Based on the biofilm formation index (BFI) of β-hemolysis-positive Vibrio strains, nine isolates exhibited a strong biofilm formation capacity, with a BFI in the range of 1.37 to 10.13. Among the 21 isolates, 6 isolates (BL18, BL82, BL84, BL85, BL90, and BL92) were tlh-positive, while trh and tdh genes were not detected in all strains. Out of 21 strains, 5 strains showed multidrug resistance (MDR) against amoxicillin/clavulanic acid, ampicillin/sulbactam, cefotaxime, cefuroxime, meropenem, and trimethoprim/sulfamethoxazole. A phylogenetic analysis of MDR Vibrio was performed based on 16s rDNA sequences using the neighbor-joining method. The five MDR isolates were identified to be Vibrio neocaledonicus (one isolate), Vibrio fluvialis (one isolate) and, Vibrio cidicii (three isolates). In addition, the antimicrobial activity of chitooligosaccharide-epigallocatechin gallate (COS-EGCG) conjugate against MDR Vibrio strains was determined. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of COS-EGCG conjugate were in the range of 64-128 µg/mL. The antimicrobial activity of the conjugate was advocated by the cell lysis of MDR Vibrio strains, as elucidated by scanning electron microscopic images. Vibrio spp. isolated from blood clams, baby clams, and Asian green mussels were highly pathogenic, exhibiting the ability to produce biofilm and being resistant to antibiotics. However, the COS-EGCG conjugate could be used as a potential antimicrobial agent for controlling Vibrio in mollusks.

Benzalkonium chloride disinfectant residues stimulate biofilm formation and increase survival of Vibrio bacterial pathogens.

Vibrio spp. are opportunistic human and animal pathogens found ubiquitously in marine environments. Globally, there is a predicted rise in the prevalence of Vibrio spp. due to increasing ocean temperatures, which carries significant implications for public health and the seafood industry. Consequently, there is an urgent need for enhanced strategies to control Vibrio spp. and prevent contamination, particularly in aquaculture and seafood processing facilities. Presently, these industries employ various disinfectants, including benzalkonium chloride (BAC), as part of their management strategies. While higher concentrations of BAC may be effective against these pathogens, inadequate rinsing post-disinfection could result in residual concentrations of BAC in the surrounding environment. This study aimed to investigate the adaptation and survival of Vibrio spp. exposed to varying concentrations of BAC residues. Results revealed that Vibrio bacteria, when exposed, exhibited a phenotypic adaptation characterized by an increase in biofilm biomass. Importantly, this effect was found to be strain-specific rather than species-specific. Exposure to BAC residues induced physiological changes in Vibrio biofilms, leading to an increase in the number of injured and alive cells within the biofilm. The exact nature of the "injured" bacteria remains unclear, but it is postulated that BAC might heighten the risk of viable but non-culturable (VBNC) bacteria development. These VBNC bacteria pose a significant threat, especially since they cannot be detected using the standard culture-based methods commonly employed for microbiological risk assessment in aquaculture and seafood industries. The undetected presence of VBNC bacteria could result in recurrent contamination events and subsequent disease outbreaks. This study provides evidence regarding the role of c-di-GMP signaling pathways in Vibrio adaptation mechanisms and suggests that c-di-GMP mediated repression is a potential avenue for further research. The findings underscore that the misuse and overuse of BAC may increase the risk of biofilm development and bacterial survival within the seafood processing chain.

Prevalence, Antibiotic-Resistance, and Growth Profile of Vibrio spp. Isolated From Fish and Shellfish in Subtropical-Arid Area.

The study aimed to determine the prevalence of different species of Vibrio spp. in fish and shellfish sold in subtropical-arid countries (United Arab Emirates). It also examined the antimicrobial resistance of the isolated species and their growth behavior upon in vitro environmental changes concerning temperature, pH, and salinity. The prevalence of Vibrio spp. in fish and shellfish samples, was 64.5 and 92%, respectively. However, Vibrio parahemolyticus were detected in a mere 7.5 and 13.0% of the samples, respectively. On the other hand, Vibrio mimicus was detected in 1.5 and 8.5% of the samples, respectively. None of the six antibiotics studied except for Sulfamethoxazole-trimethoprim were effective against fish Vibrio spp. isolates. On a similar note, three antibiotics, namely Penicillin, Daptomycin, and Vancomycin, were ineffective against the shellfish isolates. The growth of the microorganisms did not show any significant trend with changes in pH and salinity. The optimum temperature for Vibrio spp. growth was observed to be 37°C.

Conceptual Profile of Vibrio Species and the Associated Physicochemical Dynamics of Some Aquatic Reservoirs in Andoni Local Government Area of Rivers State, Nigeria

Vibrio species are autochthonous in the aquatic environment, and are among the leading causes of waterborne disease outbreaks. The ecological prevalence of Vibrio spp. is however influenced by the environmental dynamics of the reservoir system. The study was therefore aimed at assessing the physicochemical as well as seasonal factors that influence the prevalence of Vibrio spp. in some communities in Andoni Local Government Area of Rivers State. A total of 28 water samples collected in two seasons, were subjected to bacteriological and physicochemical analysis, using standard procedures. The data obtained from the study showed that the physicochemical parameters were within WHO permissible limits except for pH which had mean values within the acidic range and varied between 5.51±0.32 during the wet season, and 5.78±0.79 during the dry season. Statistical analysis of the data obtained however showed that there was a significant difference (p < 0.05) in the conductivity values with respect to location, sample type (boreholes and wells) and season, TDS, Salinity and pH were however, significantly different (p < 0.05) with respect to location only. The study on the prevalence of the Vibrio spp. in the water sources showed a prevalence rate of 29.16% in the well water samples compared to the borehole water samples with 25% mean prevalence rate. The prevalence based on location further showed that Inyorong Community had the highest prevalence rate of 50%, followed by Ngo Community with 37.5% prevalence rate, while Ukwa Community had the lowest prevalence rate of 12.5 %. Also, assessment of the seasonal prevalence of the bacteria revealed the occurrence of the isolates was 37.5% and 16.6% in the wet and dry season, respectively. The presence of Vibrio spp. in these communities in Andoni Local Government Area is of a public health concern. Regular surveillance alongside preventive measures is therefore recommended for the prevention of cholera related disease outbreaks.

Conceptual Profile of Vibrio Species and the Associated Physicochemical Dynamics of Some Aquatic Reservoirs in Andoni Local Government Area of Rivers State, Nigeria

Vibrio species are autochthonous in the aquatic environment, and are among the leading causes of waterborne disease outbreaks. The ecological prevalence of Vibrio spp. is however influenced by the environmental dynamics of the reservoir system. The study was therefore aimed at assessing the physicochemical as well as seasonal factors that influence the prevalence of Vibrio spp. in some communities in Andoni Local Government Area of Rivers State. A total of 28 water samples collected in two seasons, were subjected to bacteriological and physicochemical analysis, using standard procedures. The data obtained from the study showed that the physicochemical parameters were within WHO permissible limits except for pH which had mean values within the acidic range and varied between 5.51±0.32 during the wet season, and 5.78±0.79 during the dry season. Statistical analysis of the data obtained however showed that there was a significant difference (p < 0.05) in the conductivity values with respect to location, sample type (boreholes and wells) and season, TDS, Salinity and pH were however, significantly different (p < 0.05) with respect to location only. The study on the prevalence of the Vibrio spp. in the water sources showed a prevalence rate of 29.16% in the well water samples compared to the borehole water samples with 25% mean prevalence rate. The prevalence based on location further showed that Inyorong Community had the highest prevalence rate of 50%, followed by Ngo Community with 37.5% prevalence rate, while Ukwa Community had the lowest prevalence rate of 12.5 %. Also, assessment of the seasonal prevalence of the bacteria revealed the occurrence of the isolates was 37.5% and 16.6% in the wet and dry season, respectively. The presence of Vibrio spp. in these communities in Andoni Local Government Area is of a public health concern. Regular surveillance alongside preventive measures is therefore recommended for the prevention of cholera related disease outbreaks.

Occurrence, Seasonal Distribution, and Molecular Characterization of Vibrio vulnificus, Vibrio cholerae, and Vibrio parahaemolyticus in Shellfish (Mytilus galloprovincialis and Ruditapes decussatus) Collected in Sardinia (Italy)

In this study, we investigated the occurrence, seasonal distribution, and molecular characterization of pathogenic vibrios in Mediterranean mussels (Mytilus galloprovincialis) and grooved carpet shells (Ruditapes decussatus) from two harvesting areas of Sardinia (Italy). Samples collected before and after depuration were submitted for qualitative and quantitative determination of Vibrio spp. Vibrio spp. isolates were presumptively identified by means of biochemical methods. Identification and virulence profile of Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus were performed by molecular methods. The prevalence of Vibrio spp. in M. galloprovincialis and R. decussatus was, respectively, 96 and 77%. The averaged enumeration (mean ± standard deviation) of Vibrio spp. in samples of M. galloprovincialis and R. decussatus collected at the harvesting time was 2.04 ± 0.45 and 2.51 ± 0.65 log CFU/g, respectively. The average contamination levels in samples collected after purification were 2.28 ± 0.58 log CFU/g (M. galloprovincialis) and 2.12 ± 0.67 log CFU/g (R. decussatus). Four potentially pathogenic V. parahaemolyticus isolates (tdh+ or trh+) were recovered from grooved carpet shells samples. No isolate was tdh+/trh+. The presence of potentially pathogenic vibrios in Sardinian waters strengthens the need for rational purification practices under controlled conditions to guarantee the protection of consumers.

Comparative prevalence and characterization of Vibrio spp. isolated from live and frozen white‐leg shrimp (Litopenaeus vannamei) in Korean markets

AbstractWe evaluated the prevalence and characteristics of Vibrio spp. in frozen and live samples of white‐leg shrimp (Litopenaeus vannamei) sold in Korea. The mean total bacterial counts of frozen and live white‐leg shrimp meat were approximately 2 ×109 and 1 ×1010 CFU/g, respectively. Eight V. parahaemolyticus isolates were recovered from frozen samples, whereas a total of 40 strains including 30 V. parahaemolyticus, 8 V. alginolyticus, 1 V. harveyi, and 1 V. fluvialis were isolated from live samples. The majority (≥92%) of the Vibrio spp. isolates were positive for six extracellular enzymatic tests, while 50 and 29% of the isolates were positive for hemolysis and slime production, respectively. In virulence gene profile, all V. parahaemolyticus isolates were positive for toxR and tlh genes, but negative for tdh and trh. V. alginolyticus isolates harbored collagenase, toxR, tlh, and VPI genes in 10, 75, 86, and 63%, respectively. Besides, V. fluvialis isolate was positive for toxR, vfh, and hupO genes. Moreover, 100, 91, 50, 45, and 27% of the isolates were resistant to ampicillin, piperacillin, colistin, vancomycin, and amikacin, respectively. These results implied that white‐leg shrimp‐borne Vibrio spp. are indicative of a potential consumer health risk.Practical applicationsVibrio is a well‐known group of seafoodborne pathogenic bacteria. Since white‐leg shrimp is the most preferred shrimp variety in Korea, we sought to evaluate the prevalence and characteristics of Vibrio spp. in both frozen and live white‐leg shrimp from several retail markets. A total of 48 isolates were presumptively identified by biochemical tests. Subsequently, the gyrB gene sequencing and the neighbor‐joining phylogenetic tree confirmed the prevalence of 4 and 1 Vibrio species in live and frozen samples, respectively. Prevalence of Vibrio in frozen samples was much lower than live samples. Putative virulence of the Vibrio spp. was examined by both pathogenicity tests and PCR gene detection. Majority of the isolates were positive for pathogenicity tests and a heterogeneity in virulence gene prevalence was detected among Vibrio spp. Antibiotic susceptibility was examined by disc diffusion test for 25 antibiotics belong to 13 classes. The Vibrio isolates were highly resistant to penicillin group, however, others had different susceptibilities. In addition, we examined the total bacterial count (TBC) of the white‐leg shrimp meat by aerobic plate count method to evaluate their total bacterial prevalence. The obtained TBCs were higher than the recommended value. With regards to the results, it is worth noting that the white‐leg shrimp in Korean markets are indicative of a potential public health risk.

Prevalence of Vibrio spp. in Retail Seafood in Berlin, Germany

This study was conducted to determine the prevalence of Vibrio spp. in retail seafood in Berlin, Germany. A total of 160 raw seafood samples from supermarkets and seafood shops, consisting of shrimp ( n = 80) and bivalves ( n = 80), were investigated for the presence of Vibrio spp. using the International Organization for Standardization ISO/TS 21872 method and a multiplex PCR. The overall prevalence of Vibrio spp. in retail seafood was 55% (95% CI: 47.2 to 62.8%). The prevalence of Vibrio spp. in shrimp was slightly higher than in bivalves (57.5 versus 52.5%); however, the difference was not statistically significant. Vibrio alginolyticus was the most prevalent species (35.6%), followed by Vibrio parahaemolyticus (27.5%), Vibrio cholerae (6.3%), and Vibrio vulnificus (0.6%). None of the V. parahaemolyticus ( n = 110) isolates encoded tdh/ trh genes, whereas all V. cholerae isolates ( n = 27) were lacking ctxA. Among the chilled samples ( n = 105), the prevalence of Vibrio spp. in unpacked samples was significantly higher than in packed samples ( P = 0.006). Among the packed samples ( n = 55), no significant difference in the prevalence of Vibrio spp. was observed between chilled or frozen products. The results of this study indicated a high prevalence of Vibrio spp. in retail seafood in Germany; positive samples were detected in all types of seafood investigated. The detection of tdh/ trh-negative V. parahaemolyticus isolates should not be neglected because of previous findings on pathogenic strains lacking these virulence markers. Even though thorough cooking might limit the risk of foodborne illness caused by Vibrio, potential cross-contamination during preparation or consumption of raw and undercooked seafood might represent a risk of Vibrio infections.

Prevalence of vibrios with special reference to Vibrio parahaemolyticus in farmed penaeid shrimp, Penaeus vannamei (Boone, 1931) from selected districts of Tamil Nadu, India

Prevalence of Vibrio spp. with special reference to Vibrio parahaemolyticus (Vp) infection was assessed in Penaeus vannamei farms in Kancheepuram and Thiruvallur districts of Tamil Nadu during the period August 2014 to February 2015. Isolation and identification of bacteria from haemolymph, stomach and hepatopancreas of P. vannamei was done from all the farms for the prevalence of Vp infection. Based on the morphological, physiological and biochemical characterisation, 74 isolates were identified as Vp (35.14%), V. harveyi (21.62%), V. anguillarum (16.22%), V. campbellii (10.81%), V. mimicus (8.11%), V. alginolyticus (5.41%) and Pseudomonas aeruginosa (2.7%). The PCR results showed that there were 26 (35.14%) isolates positive for Vp specific toxR and tlh genes and negative for human pathogenic tdh and trh genes. All isolates were also negative for acute hepatopancreatic necrosis disease (AHPND) specific AP1, AP2, AP3 (pirAvp) and AP4 (pirAvp and pirBvp) genes. The study revealed that there was no AHPND causing Vp strain in farmed P. vannamei from two important coastal districts of Tamil Nadu, India.

Genetic and phenotypic analysis of Vibrio cholerae non-O1, non-O139 isolated from German and Austrian patients

Vibrio cholerae belonging to the non-O1, non-O139 serogroups are present in the coastal waters of Germany and in some German and Austrian lakes. These bacteria can cause gastroenteritis and extraintestinal infections, and are transmitted through contaminated food and water. However, non-O1, non-O139 V. cholerae infections are rare in Germany. We studied 18 strains from German and Austrian patients with diarrhea or local infections for their virulence-associated genotype and phenotype to assess their potential for infectivity in anticipation of possible climatic changes that could enhance the transmission of these pathogens. The strains were examined for the presence of genes encoding cholera toxin and toxin-coregulated pilus (TCP), as well as other virulence-associated factors or markers, including hemolysins, repeats-in-toxin (RTX) toxins, Vibrio seventh pandemic islands VSP-1 and VSP-2, and the type III secretion system (TTSS). Phenotypic assays for hemolysin activity, serum resistance, and biofilm formation were also performed. A dendrogram generated by incorporating the results of these analyses revealed genetic differences of the strains correlating with their clinical origin. Non-O1, non-O139 strains from diarrheal patients possessed the TTSS and/or the multifunctional autoprocessing repeats-in-toxin (MARTX) toxin, which were not found in the strains from ear or wound infections. Routine matrix-assisted laser desorption/ionization (MALDI-TOF) mass spectrometry (MS) analysis of all strains provided reliable identification of the species but failed to differentiate between strains or clusters. The results of this study indicate the need for continued surveillance of V. cholerae non-O1, non-O139 in Germany, in view of the predicted increase in the prevalence of Vibrio spp. due to the rise in surface water temperatures.Electronic supplementary materialThe online version of this article (doi:10.1007/s10096-013-2011-9) contains supplementary material, which is available to authorized users.

Prevalence and Population Structure of Vibrio vulnificus on Fishes from the Northern Gulf of Mexico

The prevalence of Vibrio vulnificus on the external surfaces of fish from the northern Gulf of Mexico was determined in this study. A collection of 242 fish comprising 28 species was analyzed during the course of 12 sampling trips over a 16-month period. The prevalence of V. vulnificus was 37% but increased up to 69% in summer. A positive correlation was found between the percentages of V. vulnificus-positive fish and water temperatures, while salinity and V. vulnificus-positive fish prevalence were inversely correlated. A general lineal model (percent V. vulnificus-positive fish = 0.5930 - 0.02818 × salinity + 0.01406 × water temperature) was applied to best fit the data. Analysis of the population structure was carried out using 244 isolates recovered from fish. Ascription to 16S rRNA gene types indicated that 157 isolates were type A (62%), 72 (29%) were type B, and 22 (9%) were type AB. The percentage of type B isolates, considered to have greater virulence potential, was higher than that previously reported in oyster samples from the northern Gulf of Mexico. Amplified fragment length polymorphism (AFLP) was used to resolve the genetic diversity within the species. One hundred twenty-one unique AFLP profiles were found among all analyzed isolates, resulting in a calculated Simpson's index of diversity of 0.991. AFLP profiles were not grouped on the basis of collection date, fish species, temperature, or salinity, but isolates were clustered into two main groups that correlated precisely with 16S rRNA gene type. The population of V. vulnificus associated with fishes from the northern Gulf of Mexico is heterogeneous and includes strains of great virulence potential.

Detection of Vibrio parahaemolyticus in mediterranean mussels (Mytilus galloprovincialis) in Slovenia

The aim of this study was to determine the prevalence of Vibrio parahaemolyticus in shellfish samples harvested along the Slovenian coast. Shellfish samples of Mediterranean mussels (Mytilus galloprovincialis) were collected along the Slovenian coast at four locations (Seča, Piran, Strunjan and Debeli Rtič) between 2006 and 2008. Samples were examined and analysed for the presence of V. parahaemolyticus by conventional and molecular methods. The presence of Vibrio in the samples was examined by conventional methods on plate grown bacterial cells before and after enrichment in alkaline saline peptone water (ASPW). PCR methods were used for the detection of V. parahaemolyticus-specific toxR and tlh genes and of the virulence-associated tdh and trh genes. Out of 168 samples examined, 24 were positive for toxR and tlh genes by PCR from enrichment broth. Five out of 62 (8.1%), 4 out of 32 (12.5%) and 15 out of 74 (20.2%) samples were positive in 2006, 2007 and 2008, respectively. Colonies of V. parahaemolyticus were isolated from only one sample positive for V. parahaemolyticus by PCR.

Application of Molecular Tools for the Survey of Bacterial Pathogens Associated with Crassostrea virginica (Gmelin 1791) and Crassostrea ariakensis (Fujita 1913)

Abstract The drastic decline of the eastern oyster (Crassostrea virginica) in Chesapeake Bay and other estuarine areas along the Atlantic coast of the United States has prompted officials to consider the possibility of introducing the Suminoe oyster Crassostrea ariakensis into these waters. However, the introduction of an exotic oyster species may have unforeseen and potentially harmful effects on the Bay's ecosystem. An important question to be addressed is the potential for the nonnative oyster to become a reservoir for human, fish, and shellfish bacterial pathogens. The purpose of this study is to establish and optimize methodology, and carry out a preliminary screen of C. ariakensis and C. virginica from Chesapeake Bay for the presence of Vibrio parahaemolyticus, V. vulnificus, mycobacteria, and enterobacteria, using cultivation on semiselective media and PCR. In spite of the high prevalence of Vibrio spp. in soft tissues and the shell surface of both oyster species, V. parahaemolyticus and V. vulnifi...

Application of risk management to the production chain of intensively reared fish.

Principles of risk management, as a part of risk analysis, are described with respect to their application to the production chain of intensively reared fish. According to the outcomes of the FAO/WHO Expert consultation on the Application of Risk Management (Rome, 1997), there are four steps: risk evaluation, risk management option assessment, implementation of management decisions, and monitoring and review. There is a lack of information on risk assessment for farmed fish though, regarding bacteriological hazards, the data on farmed fish pathology and microbiology suggest a potential prevalence of Vibrio spp. and Aeromonas spp. Other bacterial contaminants could be introduced on handling during selection and packaging of products. On the basis of the above qualitative risk evaluation, risk management options have been individuated. These concern the monitoring of the health status of fish during the fattening period, harvest parameters, hygiene of selection and packaging, and storage characteristics.

Effects of short term feeding of microalgae on the bacterial flora associated with juvenile Artemiafranciscana

Artemia franciscana cultivated for 2 days for use as feed for Atlantic halibut larvae ( Hippoglossus hippoglossus L.) had high numbers of associated bacteria with high counts of presumptive vibrios (TCBS-agar) and haemolytic bacteria (blood agar). The food used for the cultivation of A. franciscana, fish meal and fish oil, is a rich substrate for proliferation of opportunistic bacteria. A procedure for incubation of 2-day-old A. franciscana with the microalga Tetraselmis sp. was used to test the hypothesis that a change in the gut bacterial flora of A. franciscana could be induced by incorporating algal cells into the diet. It was expected that this would reduce bacterial proliferation in the Artemia, and introduce new bacterial species from the algal culture resulting in a more stable and diverse flora associated with the animals. The standard 2-day-old A. franciscana had 24,000±10,700 colony forming units (CFU, mean±STD) per animal with presumptive vibrios and haemolytic bacteria constituting 58% and 10% of the total, respectively. The flora was dominated by Vibrio alginolyticus-like bacteria that constituted 34 out of 40 isolates tested. During 4-h incubation the numbers of associated bacteria were reduced, on average by 75%, with the flora less dominated by V. alginolyticus. The relative diversity ( J′) of the associated bacterial flora increased from 0.17 to 0.40. A 24-h incubation to simulate first feeding conditions for halibut larvae gave further decreases in bacterial numbers associated with both treated and untreated A. franciscana. The prevalence of Vibrio was lower in these two samples, and the flora was now dominated by isolates of other genera. The relative diversity of the flora of A. franciscana increased to 0.82 and 0.63 for samples previously incubated with Tetraselmis sp. and those which were not, respectively. Data from a first feeding experiment showed that the bacterial flora of the live feed was directly transferred to the larvae. The algal component was shown to influence the numbers and composition of the associated flora of the live feed, giving A. franciscana with lower numbers of bacteria as well as a more diverse bacterial community.