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Abstract Introduction: Sea urchin diseases have been documented in several locations worldwide, with reported occurrences of bacterial, protozoan, fungal, and algal infections. Objective: This study aimed to investigate pathogen agents in populations of Arbacia lixula and Paracentrotus lividus along the coast of Gran Canaria Island (Central-East Atlantic, Spain). Methods: Sampling was conducted at San Cristobal beach, on the Northeast side of the island, where sea urchins were manually collected from depths of 1-3 m during June, July, and October 2022. Swab samples were taken from the external and internal areas of the lesions and cultured on various media plates. Results: Eight different pathogen agents, including bacteria and fungi, were identified, with Vibrio alginolyticus being the most frequently observed bacteria in all diseased sea urchin samples. Additionally, ciliated protozoans were found within the tests, potentially acting as opportunistic parasites. Conclusions: This research provides a unique perspective on bald sea urchin disease by identifying a significant number of associated pathogens, including Candida, previously unreported in diseased organisms. Furthermore, the study highlights the presence of an inflammatory response in tissues with bacterial colonies, offering crucial insights into understanding this sea urchin disease.
Resumen Introducción: Las enfermedades en los erizos de mar han sido descritas en muchas localidades alrededor del mundo, y se han asociado con la presencia de infecciones por bacterias, protozoarios, hongos y algas. Objetivo: Este estudio tuvo como finalidad investigar sobre los agentes patógenos que afectan a las poblaciones de Arbacia lixula y Paracentrotus lividus a lo largo de la costa de la Isla de Gran Canaria (Atlántico Centro-Oriental, España). Métodos: El muestreo fue llevado a cabo en la playa de San Cristóbal, al noreste de la isla, dónde los organismos fueron capturados entre 1-3 metros de profundidad, durante junio, julio y octubre del año 2022. Se tomaron muestras en la zona interna y externa de la lesión en cada organismo, y se cultivaron en varios medios de cultivo. Resultados: Fueron identificados ocho agentes patógenos diferentes, incluyendo bacterias y hongos, y siendo Vibrio alginolyticus la bacteria más frecuentemente observada en todas las muestras de erizos enfermos. Además, se observaron protozoarios ciliados dentro de los caparazones, actuando potencialmente como parásitos oportunistas. Conclusiones: Esta investigación proporciona una perspectiva única sobre la enfermedad del erizo desnudo al identificar un número significativo de patógenos asociados, incluida Candida, que no se había reportado previamente en organismos enfermos. Además, el estudio destaca la presencia de una respuesta inflamatoria en tejidos con colonias bacterianas, lo que ofrece información crucial para comprender esta enfermedad de los erizos de mar.
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Animaux , Bactéries , Arbacia/pathogénicité , ChampignonsRÉSUMÉ
@#Vibrio vulnificus is a halophilic gram-negative bacillus that can cause fulminant septicaemia in immunocompromised patients. A 67-year-old man who was immunosuppressed as a result of cytotoxic chemotherapy presented with a brief history of fever, lethargy, myalgia, and reduced oral intake. He had recently travelled to the beach to consume seafood. His blood pressure was 81/47 mm Hg, necessitating fluid resuscitation followed by inotropic support and admission to the intensive care unit. His blood culture was positive for curved gram-negative bacilli. The isolate was oxidase-positive and produced an acid butt with an alkaline slant in triple sugar iron agar. Matrix-assisted laser desorption ionization-time of flight mass spectrometry conclusively identified the isolate as V. vulnificus. Intravenous ceftazidime plus ciprofloxacin were administered, and by the fifth day of admission, he was successfully transferred out to the general ward. In total, the patient completed a 14-day course of antibiotic therapy.
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Bacteremia by non-O1/non-O139 Vibrio cholerae is a rare entity associated with high mortality rates. We report a case of non-O1/non-O139 V. cholerae bacteremia confirmed by polymerase chain reaction and agglutination tests. The clinicoepidemiological characteristics and therapeutic options for this infection are also described.
La bacteriemia por Vibrio cholerae no-O1/no-O139 es una entidad poco frecuente que se asocia con altas tasas de mortalidad. Se reporta un caso de bacteriemia por V. cholerae no-O1/no-O139 confirmado por reacción en cadena de la polimerasa y test de aglutinación. Se describen las características clinicoepidemiológicas y las opciones terapéuticas para esta infección.
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Bactériémie , Vibrio cholerae non-O1 , Facteurs de virulenceRÉSUMÉ
El cólera es una toxoinfección alimentaria ocasionada por la ingesta de agua y alimentos contaminados por el Vibrio cholerae. Es una de las enfermedades más antiguas de la humanidad y las primeras descripciones corresponden a Hipócrates. La primera epidemia documentada, sucedió en la India en 1817 y se extendió a Turquía y a los países árabes. En nuestro país, el primer brote ocurrió en 1856 en la ciudad de Bahía Blanca, asociada a la llegada de navíos con enfermos y a las deficientes condiciones sanitarias de la ciudad. Los sucesivos brotes se acompañaron de una alta mortalidad, a tal punto que el Dr. José María Penna señaló que costó más vidas a la nación que la guerra con Paraguay. En el presente artículo se analizan los sucesivos brotes de cólera en nuestro país
Cholera is a food poisoning caused by the ingestion of food and water contaminated by Vibrio cholerae. It is one of the oldest diseases of humanity and the first descriptions correspond to Hippocrates. The first documented epidemic occurred in India in 1817 and spread to Turkey and the Arab countries. In our country, the first outbreak occurred in 1856 in the city of Bahía Blanca, associated with the arrival of ships with patients and poor sanitary conditions in the city. The successive outbreaks were accompanied by high mortality, to the point that Dr. José María Penna pointed out that it cost the nation more lives than the war with Paraguay. This article analyzes the successive outbreaks of cholera in our country
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Humains , Mâle , Femelle , Choléra/histoire , Choléra/épidémiologie , Épidémies/histoireRÉSUMÉ
OBJECTIVE@#This study investigated how the natural phytophenol and potent SIRT1 activator resveratrol (RSV) regulate necroptosis during Vibrio vulnificus (V. vulnificus)-induced sepsis and the potential mechanism.@*METHODS@#The effect of RSV on V. vulnificus cytolysin (VVC)-induced necroptosis was analyzed in vitro using CCK-8 and Western blot assays. Enzyme-linked immunosorbent assays and quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry and survival analyses were performed to elucidate the effect and mechanism of RSV on necroptosis in a V. vulnificus-induced sepsis mouse model.@*RESULTS@#RSV relieved necroptosis induced by VVC in RAW264.7 and MLE12 cells. RSV also inhibited the inflammatory response, had a protective effect on histopathological changes, and reduced the expression level of the necroptosis indicator pMLKL in peritoneal macrophages, lung, spleen, and liver tissues of V. vulnificus-induced septic mice in vivo. Pretreatment with RSV downregulated the mRNA of the necroptosis indicator and protein expression in peritoneal macrophages and tissues of V. vulnificus-induced septic mice. RSV also improved the survival of V. vulnificus-induced septic mice.@*CONCLUSION@#Our findings collectively demonstrate that RSV prevented V. vulnificus-induced sepsis by attenuating necroptosis, highlighting its potency in the clinical management of V. vulnificus-induced sepsis.
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Animaux , Souris , Nécroptose , Resvératrol/usage thérapeutique , Vibrio vulnificus , Sepsie/traitement médicamenteux , Technique de WesternRÉSUMÉ
Wound infection is becoming a considerable healthcare crisis due to the abuse of antibiotics and the substantial production of multidrug-resistant bacteria. Seawater immersion wounds usually become a mortal trouble because of the infection of Vibrio vulnificus. Bdellovibrio bacteriovorus, one kind of natural predatory bacteria, is recognized as a promising biological therapy against intractable bacteria. Here, we prepared a B. bacteriovorus-loaded polyvinyl alcohol/alginate hydrogel for the topical treatment of the seawater immersion wounds infected by V. vulnificus. The B. bacteriovorus-loaded hydrogel (BG) owned highly microporous structures with the mean pore size of 90 μm, improving the rapid release of B. bacteriovorus from BG when contacting the aqueous surroundings. BG showed high biosafety with no L929 cell toxicity or hemolysis. More importantly, BG exhibited excellent in vitro anti-V. vulnificus effect. The highly effective infected wound treatment effect of BG was evaluated on mouse models, revealing significant reduction of local V. vulnificus, accelerated wound contraction, and alleviated inflammation. Besides the high bacterial inhibition of BG, BG remarkably reduced inflammatory response, promoted collagen deposition, neovascularization and re-epithelization, contributing to wound healing. BG is a promising topical biological formulation against infected wounds.
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Objective To investigate the etiological characteristics of food poisoning isolates of Vibrio parahaemolyticus (VP) from 2019 to 2021 in Zhongshan City. Methods A total of 37 strains of Vibrio parahaemolyticus isolated from 8 food poisoning incidents in Zhongshan City from 2019 to 2021 were collected, including 1 residual food isolate and 36 human isolates. The genetic correlation of Vibrio parahaemolyticus food poisoning isolates in this region was analyzed by serological typing, virulence gene detection (TLH, TDH, and TRH), drug sensitivity test, pulsed field gel electrophoresis (PFGE) and multipoint sequence typing (MLST). Results The 37 strains of Vibrio parahaemolyticus were divided into 4 serotypes: O3:K6, O10:K4, O4:K8, and O4:KUT. The tdh+ and trh- were the main virulence genotypes, accounting for 97.30% (36/37). The drug resistance rate of cefazolin was 40.54% (15 strains R, 22 strains I), and no multidrug-resistant strains were found. The 37 VP strains were divided into 23 PFGE types and 6 cluster groups, with correlation coefficients ranging from 60.4%-100%. The multipoint sequencing typing showed that the 37 VP strains were divided into 9 ST types and 3 complex groups, of which ST3 type was the main type (23 strains, 62.1%). Conclusion This study has found that the dominant virulence types of Vibrio parahaemolyticus food poisoning isolates in Zhongshan City from 2019 to 2021 are tdh+ and trh-, and 37 representative strains can be divided into 6 PFGE clusters and 9 ST types with MLST type being mainly ST3. This study has identified the rare serotype O10:K4 which has caused an increase in the proportion of food poisoning events, suggesting that we should strengthen detection and be alert to the risk of continued local epidemics of new rare serotype strains.
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@#Abstract: Objective To investigate the molecular characteristics and drug resistance of non-O1/non-O139 Vibrio cholerae in Zhongshan City, and to provide laboratory basis for cholera prevention and control. Methods The strains of non-O1/non-O139 Vibrio cholerae isolated from sporadic patients and aquatic products from 2015 to 2021 in Zhongshan city were collected. The identification and cluster analysis of the strains were analyzed by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), the ctxA virulence gene of strains were detected by real-time fluorescence quantitative PCR, the cluster analysis of the strains was analyzed by pulsed-field gel electrophoresis (PFGE), and the drug resistance of the strains were analyzed by microbroth dilution method. Results From 2015 to 2021, 33 strains of non-O1/non-O139 Vibrio cholerae were isolated from Zhongshan City, including 28 strains from sporadic patients and 5 strains from aquatic products. Through MALDI-TOF-MS identification, 33 strains of non-O1/non-O139 Vibrio cholera can be identified to the level of species, and the identification results were all Vibrio cholerae. Among 33 non-O1/non-O139 Vibrio cholerae strains, 1 strain carried the ctxA virulence gene. The drug-resistant strains accounted for 69.7% (23/33), and the multidrug resistant strains accounted for 18.2% (6/33). A total of 7 kinds of drug resistance spectrum were produced, including 3 kinds of multidrug resistant spectrum, and showed drug resistance to 8 antibiotics, among which the resistance rates to streptomycin, cefazolin and compound sulfamethoxazole were above 30%. The 33 strains of non-O1/non-O139 Vibrio cholerae were divided into 32 PFGE fingerprints with a similarity ranging from 61.7% to 100%. MALDI-TOF-MS cluster analysis divided 33 non-O1/non-O139 Vibrio cholerae strains into two clusters. Conclusions The results of molecular typing of non-O1/non-O139 Vibrio cholerae in Zhongshan City presented diversity, and no significant correlation was found between PFGE and MALDI-TOF-MS cluster analysis. The strains demonstrated various degrees of resistance to certain antibiotics, and there were multidrug-resistant and toxigenic strains. Therefore, it is necessary to alert to the harmfulness of non-O1/non-O139 Vibrio cholerae and enhance monitoring.
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@#Vibrio cholerae is a gram-negative bacterium synonymous with its namesake disease, cholera. Thus, gastrointestinal symptoms are the norm and V. cholerae is very rarely associated with skin and soft tissue infections. We describe a case of a 63-year-old Chinese woman with multiple medical comorbidities on corticosteroid therapy who developed fever and a painful swelling on her left leg after being pricked by a branch while gardening. There was no abdominal pain, vomiting or diarrhea. A diagnosis of bullous cellulitis was made clinically, and blood was sent for bacteriological culture. A beta-hemolytic commashaped gram-negative bacillus was isolated from the blood. It was also oxidase-positive and produced an acid/alkaline (A/K) reaction on triple sugar iron agar. It was identified biochemically as Vibrio cholerae. After additional testing, it was found to be of the O1 serogroup and Ogawa serotype. The infection resolved following a 10-day course of high-dose co-trimoxazole therapy.
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OBJECTIVE@#This study aimed to investigate whether the VCA0560 gene acts as an active diguanylate cyclase (DGC) in Vibrio cholerae and how its transcription is regulated by Fur and HapR.@*METHODS@#The roles of VCA0560 was investigated by utilizing various phenotypic assays, including colony morphological characterization, crystal violet staining, Cyclic di-GMP (c-di-GMP) quantification, and swimming motility assay. The regulation of the VCA0560 gene by Fur and HapR was analyzed by luminescence assay, electrophoretic mobility shift assay, and DNase I footprinting.@*RESULTS@#VCA0560 gene mutation did not affect biofilm formation, motility, and c-di-GMP synthesis in V. cholerae, and its overexpression remarkably enhanced biofilm formation and intracellular c-di-GMP level but reduced motility capacity. The transcription of the VCA0560 gene was directly repressed by Fur and the master quorum sensing regulator HapR.@*CONCLUSION@#Overexpressed VCA0560 functions as an active DGC in V. cholerae, and its transcription is repressed by Fur and HapR.
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Vibrio cholerae/génétique , Biofilms , Détection du quorum , Mutation , Régulation de l'expression des gènes bactériens , Protéines bactériennes/génétiqueRÉSUMÉ
Pullulanase is a starch debranching enzyme, which is difficult in secretory expression due to its large molecular weight. Vibrio natriegens is a novel expression host with excellent efficiency in protein synthesis. In this study, we achieved secretory expression of the full-length pullulanase PulA and its truncated mutant PulN2 using V. natriegens VnDX strain. Subsequently, we investigated the effects of signal peptide, fermentation temperature, inducer concentration, glycine concentration and fermentation time on the secretory expression. Moreover, the extracellular enzyme activities of the two pullulanases produced in V. natriegens VnDX and E. coli BL21(DE3) were compared. The highest extracellular enzyme activity of PulA and PulN2 in V. natriegens VnDX were 61.6 U/mL and 64.3 U/mL, which were 110% and 62% that of those in E. coli BL21(DE3), respectively. The results indicated that V. natriegens VnDX can be used for secretory expression of the full-length PulA with large molecular weight, which may provide a reference for the secretory expression of other large molecular weight proteins in V. natriegens VnDX.
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Escherichia coli/génétique , Fermentation , Vibrio/génétiqueRÉSUMÉ
This study explored three molecular typing methods for Vibrio parahaemolyticus(VP)in Liaoning Province in 2020,to assess the correlation among the three methods and the genetic relationships among between strains;analyze the epi-demic trends and distribution patterns of VPin Liaoning Province;and provide reliable technical support for the prevention and control of foodborne diseases.Serum typing,PFGE,REP-PCR,and ERIC-PCR molecular typing and cluster analysis were performed on 44 VP isolates from Liaoning Province in 2020.A total of 44 isolated strains were divided into 15 serotypes,and 8 isolated strains could not be classified.The serotypes were primarily O3 group,O1 group,and O2 group.Clinical isolates had high molecular similarity,whereas food isolates had low molecular similarity.The resolution(DI)of PFGE was 0.986,that of REP-PCR was 0.947,and that of ERIC-PCR was 0.935.The molecular similarity between serotype O3 and O1 group strains was high.The epidemic serotypes of isolated VP strains in Liaoning Province in 2020 were consistent with those from the past 5 years.The resolution of the PFGE typing method was better than that of REP-PCR and ERIC-PCR;moreover,REP-PCR had better resolution than ERIC-PCR.These three typing methods showed good intercorrelation.The O3 group strains are likely to originate from the O1 group strains.When a foodborne disease outbreak is caused by VP,laboratories with conditions can apply these three methods to trace the source of the pathogenic bacteriaquickly and effectively.
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Aims@#The Indo-Pacific coral populations are under increasing threats from bleaching events and coral disease outbreaks. However, there is a significant gap in data and research on coral diseases in Malaysian waters. This study aimed to assess the prevalence of coral diseases and signs of compromised health at 27 reef sites in the coastal waters of Kota Kinabalu, Sabah.@*Methodology and results@#We conducted coral surveys using the Coral Video Transect (CVT) method and measured the prevalence using Coral Point Count with Excel Extension (CPCe) software. Our findings indicated that the majority of reefs appeared healthy (82.9% ± 1.8), while a smaller percentage displayed signs of disease (5.0% ± 0.6) or compromised health (12.1% ± 1.5). Reef sites exposed to higher levels of human activities exhibited a greater prevalence of coral diseases (e.g. yellow band disease, ulcerative white spots and skeletal eroding band) and signs of compromised health (e.g. sediment necrosis, skeletal damage and algal overgrowth). A total of 51 scleractinian hard coral genera were affected, with Porites and Acropora being the most predominantly affected by sediment necrosis and skeletal damage, respectively. A review of molecular approaches identified various coral pathogens, including Vibrio spp., which could potentially contribute to the occurrence of coral disease. @*Conclusion, significance and impact of study@#Unsustainable coastal development with unregulated human activities can exacerbate the severity of coral diseases and signs of compromised health. Therefor
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Objective To prepare a biomimetic nano carrier macrophage membrane hybrid liposome by heterozygous macrophage membrane and liposome, which could be used for the clearance and toxicity inhibition of Vibrio vulnificus hemolysin A (VvhA). Methods Macrophage membrane was extracted and hybridized with liposome by thin-film evaporation combined extrusion method. The hybridized liposome of macrophage membrane was constructed and characterized. The in vitro detoxification ability of the hybridized vector was evaluated by hemolysis test and cytotoxicity test. The detoxification ability of the vector was evaluated by mouse skin infection model. Results Anti toxoid studies in vivo and in vitro showed that the anti-hemolysis rate of macrophage membrane heterozygous liposomes in vitro reached 97.03%, which could effectively inhibit the skin ulceration in subcutaneous infected mice and make the survival rate of abdominal infected mice reach 80%. Conclusion The constructed macrophage membrane hybrid liposome had high detoxification ability, which could provide a potential solution and research basis for the prevention and treatment of Vibrio vulnificus infection.
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Aims@#Vibrio harveyi is a serious pathogen for marine organisms particularly in hatcheries and grow-out ponds that attack their immune system. The rapid detection of V. harveyi is urgently needed to prevent bacterial spread. Here we described a rapid and specific visual detection method based on the Loop-Mediated Isothermal Amplification in combination with Lateral Flow Dipstick (LAMP-LFD). @*Methodology and results@#A set of six novel primers were designed to target the toxR gene. These include the biotin-labelled inner primer that complements specifically to the target sequences. The resulting biotinylated LAMP amplicons were hybridised to the FAM-labelled probe resulting in lateral flow detection on the dipstick. The addition of loop primers improved the reaction time of LAMP by more than half and rapid detection was observed within 10-15 min. In comparison, the sensitivity of PCR-UV analysis was only at 104 copies while LAMP-LFD was able to detect lower amounts at 103 copies. The LFD provided higher specificity and selectivity since hybridization with specific probes to the LAMP amplicons was employed. In addition, detection of V. harveyi infected grouper was successful using the LAMP-LFD method described here. @*Conclusion, significance and impact of study@#LAMP-LFD is specific to V. harveyi. Our method provides a useful tool to rapidly detect and monitor the outbreaks of the pathogen.
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Objective Establishing animal model of Vibrio vulnificus(V.vulnificus)early infection via respiratory tract,to observe the survival,pathological changes of target organs and the expression changes of inflammatory cytokines in model mice,and to provide references for the relevant prevention and treatment strategies.Methods A total of 24 healthy female BALB/c mice(8 to 10 weeks old)were randomly divided into 4 groups(6 mice per group),including control group and three infection groups(low,medium and high concentration of infection,respectively),based on which the V.vulnificus infection models were established by intranasal administration.The survival statistics,status of defecation,hair and respiration as well as mental state of mice were monitored during 0-12 h early infection progress.Hematoxylin-eosin(HE)staining was performed on the important organs of mice to analyze the pathological manifestations,and immunohistochemical staining was used to detect the expression of interleukin(IL)-6,IL-10,interferon-γ(IFN-γ)and tumor necrosis factor-α(TNF-α)in the target organs.Mouse inflammation panel combined with flow cytometry was used to further detect the changes of multiple inflammatory and anti-inflammatory cytokines in serum.Results V.vulnificus infection via respiratory tract caused mice deterioration in survival rate,defecation,hair status,respiratory tract and mental state within 12 h.HE pathological analysis showed inflammatory cell infiltration and cell necrosis in ileum,lung,liver and spleen of mice in different infection groups,and the injury was much severer in high concentration of infection group.Immunohistochemical results reflected the positive expression rates of IL-6,IL-10,IFN-γ and TNF-α in ileum,lung,liver and spleen of mice in medium and high concentration of infection groups were significantly higher than those in control group(P<0.05).The results of mouse inflammation panel and flow cytometry showed that compared with the control group,the expression levels of TNF-α and monocyte chemotactic protein(MCP)-1 in all three infection groups were significantly increased(P<0.05),and the expression level of IL-27 significantly decreased(P<0.05);the expression levels of IL-1β,IL-6,IL-17A and granulocyte-macrophage colony-stimulating factor(GM-CSF)were significantly increased in medium and high concentration of infection groups(P<0.05);the expression levels of IL-1α,IL-23,IL-12p70 and IFN-γ were significantly increased in high concentration of infection group(P<0.05).Conclusions V.vulnificus infection progressed rapidly through respiratory tract in mice,and lung,intestine,liver and spleen were major target organs.Accompanied by increased secretion of multiple serum inflammatory cytokines,V.vulnificus infection through respiratory tract might further causes severe inflammatory reaction in hosts.
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Objective To evaluate the risk of disease of Vibrio parahaemolyticus in aquatic products of raw food animals for population in guangzhou,and determine risk management points. Methods VP quantitative detection was carried out in aquatic products of raw food animals sold in Guangzhou from 2009 to 2022.sQMRA was applied to assess Vibrio parahaemolyticus risk of aquatic products of raw food animals. According to stratified analysis based on the pollution of Vibrio parahaemolyticus and evaluation results,carry out risk management and analysis. Results Among the 98 samples were detected positive of VP from 1 343 samples from 2009 to 2022 , with an overall positive rate of 7.30%.The number of Vibrio parahaemolyticus infection cases caused by eating aquatic products of raw food animals in Guangzhou was 3012. If the proportion of raw food is reduced , the number of Vibrio parahaemolyticus infection cases will be significantly reduced. The number of cases caused by eating raw fash will be reduced from 2128 to 217.The detection rate of Vibrio parahaemolyticus in raw fresh water products was much higher than that in marine products. The probability of infection in the population was higher. The number of cases caused by eating raw fash was the highest.The detection rate of Vibrio parahaemolyticus was higher in raw crustaceans and molluscs. The incidence of Vibrio parahaemolyticus infection cases caused by eating raw fash in the four quarters varied from high to low as such sequence ,4.93×10-5 in the three quarters , 2.53×10-5 in the second quarter , 2.40×10-5 in the first quarter ,1.77×10-5 in the fourth quarter . Conclusion The risk of disease of Vibrio parahaemolyticus in aquatic products of raw food animals was higher. The public health education should be done well. Aquatic products should be cooked thoroughly before eating . Reduce the intake of raw aquatic products and avoid cross contamination. Focus on the risks of summer and autumn seasons and seafood such as crustaceans and molluscs. Concentrate on scientific research on Vibrio parahaemolyticus pollution of fresh water products.
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ObjectiveTo ascertain the causes of a food poisoning incident and provide references for the prevention of similar incidents in the future. MethodsCase investigation was conducted through field epidemiological investigation methods， and suspicious meals and foods were searched by the analytical epidemiological method. A food hygiene investigation was conducted in the establishment involved and samples of suspicious food， processing steps， and cases were collected for laboratory testing. ResultsA total of 91 individuals meeting the case definition were identified， resulting in an attack rate of 14.97% （91/608）. The main clinical manifestations included abdominal pain （97.80%）， diarrhea （84.62%）， nausea （62.64%）， vomiting （72.53%）， fever （12.09%）， and increased white blood cells （90.11%）. The peak incidence occurred from 16：00 to 18：00 on June 15. The epidemic curve showed a point-source exposure pattern， with an incubation period of 1 h minimum and 10 h maximum， and an average of 5 h. Analytical epidemiological studies indicated that lunch on June 15 was the suspicious meal （χ2=38.78， P<0.001）， and those who consumed cold-dressed tofu with preserved eggs had a significantly higher risk of falling ill compared to non-consumers （χ2=105.21， P<0.001）. Laboratory testing results revealed Vibrio parahaemolyticus detected in 1 employee’s anal swab and 18 cases’ anal swabs. Staphylococcus aureus was detected in 1 food ingredient and 1 case’s anal swab. The remaining samples tested negative. ConclusionThe cause of this food poisoning incident is Vibrio parahaemolyticus. The cause is the canteen’s supply of cold-dressed tofu with preserved eggs beyond its permissible business scope， potentially leading to cross-contamination during food processing. Regulatory authorities should strengthen routine law enforcement inspections and monitoring. Food service establishments should strengthen food safety awareness， standardize operational procedures in strict accordance with relevant national laws and regulations and food safety standards， and strive to reduce the occurrence of foodborne disease incidents at their source.
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ObjectiveIn this paper， the cause of an outbreak of foodborne disease in Huzhou City was analyzed， which may help avoid the recurrence of such incidents. MethodsThrough the field epidemiological investigation， the case definition was formulated and the questionnaire survey was carried out in the case group and the control group. In addition， the chi-square test and logistic regression method were used to identify the factors affecting the outbreak. The patient stool samples， food samples， environmental samples and water samples were collected and used for the laboratory test. The PFGE molecular typing was conducted on the isolated positive strains. ResultsThe number of people exposed during the same period was 410， and the number of possible cases was 18， with an incidence of 4.39%. Generally， the main symptoms were abdominal pain and diarrhea， accompanied by nausea， fatigue， fever and others. For case-control analysis， 17 of the 18 patients were included in the case group， and 19 non-patients were into control group. The results suggested that the risk factors were blanched deep-water shrimp（OR=19.42， 95%CI=1.06‒357.02， P=0.046）and steamed Ao Long （Australian lobster） with garlic and vermicelli （OR=22.01， 95%CI=1.24‒390.70， P=0.035）. According to the laboratory test results Vibrio parahaemolyticus （VP） was positive in 5 cases， and the serum type was is O10∶K4. In the reserved food， VP was positive in the samples of steamed Australian lobster with garlic vermicelli and lamb chops. The serum type was O5∶Kut. ConclusionThis incident was an outbreak of foodborne disease caused by the consumption of wedding food contaminated by VP. The dinner was served by Hotel B on September 17. Moreover， the suspicious foods include the blanched deep-water shrimp and steamed lobster with garlic vermicelli.
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@#Abstract: Objective To understand the contamination status, drug resistance, virulence gene carrying status, and molecular typing characteristics of Vibrio parahaemolyticus (VP) in aquatic products sold in Nanchang City. Methods A total of 170 commercial crayfishes, freshwater fish frogs and related smears samples were collected from various farmers' markets in Nanchang from March to September 2021. The strains of V. parahaemolyticus were detected and isolated from the samples. Antibiotic resistance test, virulence gene test, and pulsed-field gel electrophoresis (PFGE) molecular typing analysis were carried out. Results Among the collected samples, V.parahaemolyticus was only isolated from crayfish and crayfish smear samples, with a total of 35 strains of VP isolated. No V.parahaemolyticus strain was isolated from other freshwater fish, frogs, and their smear samples. Among the 17 common antibiotics tested, only two trains showed resistance to ampicillin, and one strain to streptomycin, , and all were sensitive to other antibiotics; all 35 strains of V. parahaemolyticus carried the gene, but only one strain carried the heat-resistant related hemolysin gene trh, and no direct heat-resistant hemolysin gene tdh positive strain was found; PFGE pattern clustering showed that there was no strain with the same PFGE pattern, and there was no obvious dominant cluster among these strains, and their genetic relationship was relatively distant. Conclusions The contamination of V. parahaemolyticus in small and medium-sized crayfish sold in the market in Nanchang City is relatively serious. The V. parahaemolyticus isolates in these polluted crayfish generally do not carry key virulence genes such as tdh, are sensitive to common antibiotics, and only have low-level resistance to ampicillin and streptomycin. PFGE pattern clustering showed that V. parahaemolyticus does not have no obvious dominant cluster, and these strains have rich genetic diversity, indicating that they may have different sources.