Characterization of Vibrio parahaemolyticus isolated from clinical specimens and oysters in Thailand.

INTRODUCTION: Vibrio parahaemolyticus is a common pathogen that can cause seafood-borne gastroenteritis in humans. We determined the prevalence and characteristics of V. parahaemolyticus isolated from clinical specimens and oysters in Thailand. METHODOLOGY: Isolates of V. parahaemolyticus from clinical specimens (n = 77) and oysters (n = 224) were identified by biochemical testing, polymerase chain reaction (PCR) assays, and serotyping. The toxin genes, antimicrobial resistance, and ß-lactamase production were determined. RESULTS: A total of 301 isolates were confirmed as V. parahaemolyticus by PCR using specific primers for the toxR gene. The majority of clinical isolates carried the tdh+/trh- genotype (82.1%), and one of each isolate was tdh-/trh+ and tdh+/trh+ genotypes. One isolate from oyster contained the tdh gene and another had the trh gene. Twenty-six serotypes were characterized among these isolates, and O3:K6 was the most common (37.7%), followed by OUT:KUT, and O4:K9. In 2010, most clinical and oyster isolates were susceptible to antibiotics, with the exception of ampicillin. In 2012, clinical isolates were not susceptible to cephalothin (52.4%), streptomycin (95.2%), amikacin (66.6%), kanamycin (61.9%), and erythromycin (95.2%), significantly more frequently than in 2010. More than 95% of isolates that were not susceptible to ampicillin produced ß-lactamase enzymes. CONCLUSIONS: We found toxin genes in two oyster isolates, and the clinical isolates that were initially determined to be resistant to several antibiotics. Toxin genes and antimicrobial susceptibility profiles of V. parahaemolyticus from seafood and environment should be continually monitored to determine the spread of toxin and antimicrobial resistance genes.

Antimicrobial susceptibility profile and molecular characterization of Vibrio parahaemolyticus strains isolated from imported shrimps.

Vibrio parahaemolyticus is a threat to human health and one of the leading bacterial causes of seafood-borne infection worldwide. This pathogen is autochtonous in the marine environment and is able to acquire antimicrobial resistance (AMR) mechanisms, which is a global concern. However, the emergence of AMR V. parahaemolyticus strains in seafood is still understudied, as interpretation criteria for this species for antimicrobial susceptibility tests are limited in the literature. In this study, we investigated the susceptibility profiles to clinically important antibiotics and the associated genetic determinants of V. parahaemolyticus isolates cultured from imported shrimps. Based on the analysis of the resistance phenotypes of 304 V. parahaemolyticus isolates, we have defined experimental epidemiological cutoff values (COWT) for 14/15 antibiotics tested. We observed that 19.1% of the bacterial isolates had acquired resistance to at least one antibiotic class. The highest number of resistance was associated with tetracycline (14.5% of the strains) and trimethoprim-sulfamethoxazole (3.6%). Moreover, seven strains were multidrug-resistant (MDR, resistant to at least three antibiotic classes). The most frequently identified genes in these strains were aph(3″)-Ib/aph(6)-Id (aminoglycoside resistance), sul2 (sulfonamide), tet(59) (tetracycline), and floR (chloramphenicol). The SXT/R391 family ICE and class 1 integron-integrase genes were detected by PCR in three and one MDR V. parahaemolyticus strains, respectively. Consequently, V. parahaemolyticus in seafood can act as a reservoir of AMR, constituting a health risk for the consumer.IMPORTANCEOur study on "Antimicrobial Resistance Profiles and Genetic Determinants of Vibrio parahaemolyticus Isolates from Imported Shrimps" addresses a critical gap in understanding the emergence of antimicrobial resistance (AMR) in this seafood-associated pathogen. Vibrio parahaemolyticus is a major cause of global seafood-borne infections, and our research reveals that 19.1% of isolates from imported shrimps display resistance to at least one antibiotic class, with multidrug resistance observed in seven strains. Importantly, we establish experimental epidemiological cutoff values for antibiotic susceptibility, providing valuable criteria specific to V. parahaemolyticus. Our findings underscore the potential risk to consumers, emphasizing the need for vigilant monitoring and intervention strategies. This study significantly contributes to the comprehension of AMR dynamics in V. parahaemolyticus, offering crucial insights for global public health. The dissemination of our research through Microbiology Spectrum ensures broad accessibility and impact within the scientific community and beyond.

Antimicrobial susceptibility and genomic characterization of Vibrio parahaemolyticus isolated from aquatic foods in 15 provinces, China, 2020.

Prevalent in marine, estuarine and coastal environments, Vibrio parahaemolyticus is one of the major foodborne pathogens which can cause acute gastroenteritis through consumption of contaminated food. This study encompassed antimicrobial resistance, molecular characteristics and phylogenetic relationships of 163 V. parahaemolyticus isolated from aquatic foods across 15 provinces in China. The isolates showed high resistance rates against ampicillin (90.80 %, 148/163) and cefazolin (72.39 %, 118/163). Only 5 isolates demonstrated multi-drug resistance (MDR) phenotypes. A total of 37 different antibiotic resistance genes (ARGs) in correlation with seven antimicrobial categories were identified. tet(34) and tet(35) were present in all 163 isolates. Other most prevalent ARGs were those conferring resistance to ß-lactams, with prevalence rate around 18.40 % (30/163). The virulence genes tdh and trh were found in 17 (10.43 %) and 9 (5.52 %) isolates, respectively. Totally 121 sequence types (STs) were identified through whole genome analysis, among which 60 were novel. The most prevalent sequence type was ST3 (9.20 %, 15/163), which shared the same genotype profile of trh_, tdh+ and blaCARB-22+. Most of the tdh+V. parahaemolyticus isolates was clustered into a distinctive clade by the phylogenetic analysis. Our study showed that the antimicrobial resistance of V. parahaemolyticus in aquatic foods in China was moderate. However, the emerging of MDR isolates implicate strengthened monitoring is needed for the better treatment of human V. parahaemolyticus infections. High genetic diversity and virulence potential of the isolates analyzed in this study help better understanding and evaluating the risk of V. parahaemolyticus posed to public health.

Virulence phenotypes differ between toxigenic Vibrio parahaemolyticus isolated from western coasts of Europe.

Vibrio parahaemolyticus is the leading bacterial cause of gastroenteritis associated with seafood consumption worldwide. Not all members of the species are thought to be pathogenic, thus identification of virulent organisms is essential to protect public health and the seafood industry. Correlations of human disease and known genetic markers (e.g. thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH)) appear complex. Some isolates recovered from patients lack these factors, while their presence has become increasingly noted in isolates recovered from the environment. Here, we used whole-genome sequencing in combination with mammalian and insect models of infection to assess the pathogenic potential of V. parahaemolyticus isolated from European Atlantic shellfish production areas. We found environmental V. parahaemolyticus isolates harboured multiple virulence-associated genes, including TDH and/or TRH. However, carriage of these factors did not necessarily reflect virulence in the mammalian intestine, as an isolate containing TDH and the genes coding for a type 3 secretion system (T3SS) 2α virulence determinant, appeared avirulent. Moreover, environmental V. parahaemolyticus lacking TDH or TRH could be assigned to groups causing low and high levels of mortality in insect larvae, with experiments using defined bacterial mutants showing that a functional T3SS1 contributed to larval death. When taken together, our findings highlight the genetic diversity of V. parahaemolyticus isolates found in the environment, their potential to cause disease and the need for a more systematic evaluation of virulence in diverse V. parahaemolyticus to allow better genetic markers.

Epidemiological and Genomic analysis of Vibrio parahaemolyticus isolated from imported travelers at the port of Shanghai, China (2017-2019).

BACKGROUND: Vibrio parahaemolyticus is the predominant etiological agent of seafood-associated foodborne illnesses on a global scale. It is essential to elucidate the mechanisms by which this pathogen disseminates. Given the existing research predominantly concentrates on localized outbreaks, there is a pressing necessity for a comprehensive investigation to capture strains of V. parahaemolyticus cross borders. RESULTS: This study examined the frequency and genetic attributes of imported V. parahaemolyticus strains among travelers entering Shanghai Port, China, between 2017 and 2019.Through the collection of 21 strains from diverse countries and regions, Southeast Asia was pinpointed as a significant source for the emergence of V. parahaemolyticus. Phylogenetic analysis revealed clear delineation between strains originating from human and environmental sources, emphasizing that underlying genome data of foodborne pathogens is essential for environmental monitoring, food safety and early diagnosis of diseases. Furthermore, our study identified the presence of virulence genes (tdh and tlh) and approximately 120 antibiotic resistance-related genes in the majority of isolates, highlighting their crucial involvement in the pathogenesis of V. parahaemolyticus. CONCLUSIONS: This research enhanced our comprehension of the worldwide transmission of V. parahaemolyticus and its antimicrobial resistance patterns. The findings have important implications for public health interventions and antimicrobial stewardship strategies, underscoring the necessity for epidemiological surveillance of pathogen at international travel hubs.

Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters / Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters.

The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains (n=70) isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL), caseinase (CAS), elastase (ELAS), phospholipase (PHOS), lipase (LIP), amilase (AML) and DNase. All enzymes, except elastase, were detected in more than 60

of the strains. The most recurrent enzymatic profiles were AML + DNase + PHOS + GEL + LIP (n=16; 22.9

) and AML + CAS + DNase + PHOS + GEL + LIP (n=21; 30

). Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters.

Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters. / Multiple enzymatic profiles of Vibrio parahaemolyticus strains isolated from oysters.

The enzymatic characterization of vibrios has been used as a virulence indicator of sanitary interest. The objective of this study was to determine the enzymatic profile of Vibrio parahaemolyticus strains (n=70) isolated from Crassostrea rhizophorae oysters. The strains were examined for the presence of gelatinase (GEL), caseinase (CAS), elastase (ELAS), phospholipase (PHOS), lipase (LIP), amilase (AML) and DNase. All enzymes, except elastase, were detected in more than 60

of the strains. The most recurrent enzymatic profiles were AML + DNase + PHOS + GEL + LIP (n=16; 22.9

) and AML + CAS + DNase + PHOS + GEL + LIP (n=21; 30

). Considering the fact that exoenzyme production by vibrios is closely related to virulence, one must be aware of the bacteriological risk posed to human health by the consumption of raw or undercooked oysters.

Características de Vibrio parahaemolyticus isolados de mexilhões (Perna perna) comercializados em Niterói, Rio de Janeiro / Characteristics of Vibrio parahaemolyticus isolated from mussels (Perna perna) commercialized at Niterói, Rio de Janeiro

O ecossistema marinho é o habitat natural de bactérias como Vibrio parahaemolyticus, um importante patógeno causador de gastrenterite humana associada ao consumo de alimentos marinhos. Na presente investigação, foi avaliada a presença de V. parahaemolyticus a partir de 86 amostras de mexilhões in natura e pré-cozidos. Vibrio parahaemolyticus foi isolado a partir de 11,6 por cento dos mexilhões in natura e pré-cozidos avaliados. Todas as cepas avaliadas demonstraram-se urease positivas e 28,5 por cento Kanagawa positivas sugerindo um potencial patogênico para o homem. Houve a predominância do sorotipo O10:K52 e a identificação da cepa emergente O3:K6. Esses resultados apontam para a relevância epidemiológica de V. parahaemolyticus em casos de gastrenterite humana após consumo de mexilhões sem cozimento adequado (100°C/15min). Além disso, é importante alertar as autoridades de Vigilância Sanitária no Brasil quanto a sua presença na cadeia alimentar e seus riscos para a Saúde Pública.

The marine ecosystem is the natural habitat of bacteria like Vibrio parahaemolyticus, an important pathogen that cause human gastroenteritis associated with seafood consumption. In the present investigation, the presence of V. parahaemolyticus in 86 in natura and precooked mussel samples was evaluated. Vibrio parahaemolyticus was isolated from 11.6 percent of the in natura and precooked mussels. All strains tested were urease-positive and 28.5 percent were Kanagawa-positive, which suggests that they have pathogenic potential for humans. There was predominance of the O10:K52 serotype and the emerging O3:K6 strain was identified. These results show the epidemiological relevance of V. parahaemolyticus in cases of human gastroenteritis following mussel consumption without adequately cooking them (100°C/15min). Moreover, it is important to alert the Brazilian Sanitary Surveillance authorities regarding their presence in the food chain and their public health risks.

Revisión y recomendaciones para el manejo de diarrea por Vibrio parahaemolyticus / Review and guidelines for treatment of diarrhea caused by Vibrio parahaemolyticus

A contar del año 1998 se han presentado en Chile tres brotes epidémicos por Vibrio parahaemolyticus, el último de ellos durante el verano del 2005, que afectó a más de 10.000 personas. Los afectados presentaron un cuadro clínico caracterizado por diarrea, náuseas, vómitos, dolor abdominal y fiebre; 6 por ciento de los casos tuvo leucocitos fecales positivos y un paciente falleció. La cepa predominante en los tres brotes ha sido la pandémica O3: K6. El diagnóstico de V. parahaemolyticus se realizó con la confirmación microbiológica de las cepas y tipificación o por asociación epidemiológica. Las cepas fueron susceptibles in vitro a tetraciclina, cefalosporinas de tercera generación, quinolonas y cloranfenicol no observándose susceptibilidad a ampicilina. Todos los casos se asociaron al consumo de mariscos crudos o insuficientemente cocidos. Por la repercusión de este brote, el Ministerio de Salud impulsó la formación de una comisión multidisciplinaria para actualizar los aspectos epidemiológicos, clínicos y microbiológicos, y elaborar una guía de recomendaciones en el manejo de esta infección.

Enumeração e identificação de Vibrio parahaemolyticus em lulas frescas comercializadas no município de Niterói RJ Brasil / Enumeration and identification of Vibrio parahaemolyticus in fresh squids commercialized at Niterói, Rio de Janeiro State, Brazil

Com o objetivo de verificar as condições higiênico-sanitárias do pescado comercializado no município de Niterói, efetuou-se um estudo sobre a enumeração e identificação de Vibrio parahaemolyticus em lulas frescas. Foram utilizadas 50 amostras de lulas frescas, identificadas como pertencentes à espécie Oorytheutis brasiliensís Blainville, 1823. A identificação e enumeração do V. parahaemolyticus foram baseadas nos métodos descritos pela lnternational Commission on Microbiological Specifications for Foods - ICMSF (1983). A classificação de Heiberg (1936) foi utilizada como teste complementar. O V. parahaemolyticus foi identificado em três (6%) amostras, sendo que, em uma o vibrio se desenvolveu em meio com concentração salina a 10%, na prova de halofilismo. O V. parahaemolyticus apresentou os NMPs (Número Mais Provável) com média de 19,3.bactérias/g. As três amostras de V. parahaemolyticus submetidas à classificação de Heiberg apresentaram perfil compatível com o grupo VIl (Sacarose -, Manose + e Arabinose +). Concluiu-se que, mesmo sob comercialização inadequada, com manipulação e resfriamento precários, as amostras analisadas apresentaram o V. parahaemolyticus com frequências e NMPs baixos.

A study on the enumeration and identification of Vibrio parahaemolyticus in freshsquids in Niterói was undertook aiming at checking the hygienic-sanitary conditions of fish commercialized in that City. Fifty fresh squids (Oorytheutis brasiliensis, Blainville, 1823). Methods described by the lnternational Comission on Microbiological Specification for Foods-ICMSF (1983) were used to identify and enumerate V. parahaemoiyticus and Heiberg's classi-fication was a complementai test. v. parahaemoiyticus was identified in three samples (6%); in one of them it grew in an environment with 10% salt concentration during halophilism probe. Most probable number (MPN) average for V. parahaemoiyticus was 19,3 bacteria per gram. The three samples submitted to Heiberg's classification showed a profile compatible with group VIl (sacarose-, manose+, arabinose-). We concluded that, even under inadequate commercialization, manipulation and refrigeration conditions, V. parahaemolyticus frequencies and MPNs are low.

Caracterizaçäo sorológica de amostras de Vibrio Parahaemolyticus isoladas de peixes capturados no litoral brasileiro / Serological characterization of strains of Vibrio parahaemolyticus isolated from fishis caugth off the Brazilian coast

Em 82 peixes de origem marinha e de diferentes espécies, capturados na faixa de litoral compreendida entre Bahia e Rio Grande do Sul, foram detectados 45 ou 54, 8 por cento portadores de Vibrio parahaemolyticus, propiciando o isolamento de 71 culturas. Na caracterizaçäo sorológica (0: K), 13 sorotipos foram identificados (24 ou 33, 7 por cento) e 47 ou 66, 1 por cento das amostras só permitiram o reconhecimento da estrutura "O".os sorotipos mais incidentes foram: 02: k28; 05: K17; 01: 32 e 02: K12; nos grupos sorológicos predominaram 02; 04; 05 e 03. Näo foi evidenciado qualquer vínculo de espécies de peixes com determinados sorotipos ou sorogrupos tampouco, os níveis de isolamento sofreram a influência da sszonalidade.