Articles de revues : « Vibrio cholerae »

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Daniszewski, Piotr. « Vibrio cholerae - As Biological Weapons ». International Letters of Social and Humanistic Sciences 9 (septembre 2013) : 65–73. http://dx.doi.org/10.18052/www.scipress.com/ilshs.9.65.

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Terrorism is defined as use of unlawful violence or threat of unlawful violence to indulge fear; intended to coerce or to intimidate governments or societies in the pursuit of goals that are generally political, social or religious. Bioterrorism is terrorism by intentional release or dissemination of biological agents, mainly bacteria or viruses. Use of biological weapons is attractive from the terrorists’ point of view because of low production costs, major range and easiness of transmission. The first mention of the use of primitive biological weapons date back to the 6th century. Use of plague-infested corpses as offensive means in the 14th century caused a spread of bubonic plague through the whole Europe. The biggest development of biological weapons took place in the interwar period and in the cold war era. Biological weapon trails and research were conducted by super powers such as USSR, UK, USA and Japan. At the beginning of the 20th century a new form of bioterrorism occurred, which put humanity in the face of a terrifying threat. Cholera is a deadly disease that has caused a worldwide phenomenon throughout history. Its imperative weapon, the Vibrio cholerae bacterium, has allowed cholera to seize control and wipe out a huge percentage of the human population. V. cholerae’s toxins are the primary causes of cholera’s lethal symptoms. The bacterium contains toxins that help it accomplish its job of invading the human system and defeating the body’s powerful immune system. With its sibling bacterium Escherichia coli, V. cholerae has become one of the most dominant pathogens in the known world. V. cholerae’s strategies in causing the infamous deadly diarrhea have been widely studied, from the irritation of the intestinal epithelium to the stimulation of capillary leakage, as well as the internal effects of the disease such as the Peyer’s patches on the intestinal walls. Overall, the Vibrio cholera bacterium has made cholera a tough disease to overcome, and because of its deadly virulence factors, cholera has become one of the most frightening diseases a human body could ever encounter. Vibrio cholerae is a Gram-negative, comma-shaped bacterium. Some strains of V. cholerae cause the disease cholera. V. cholerae is facultatively anaerobic and has a flagellum at one cell pole. V. cholerae was first isolated as the cause of cholera by Italian anatomist Filippo Pacini in 1854, but his discovery was not widely known until Robert Koch, working independently 30 years later, publicized the knowledge and the means of fighting the disease. V. cholerae pathogenicity genes code for proteins directly or indirectly involved in the virulence of the bacteria. During infection, V. cholerae secretes cholera toxin, a protein that causes profuse, watery diarrhea. Colonization of the small intestine also requires the toxin coregulated pilus (TCP), a thin, flexible, filamentous appendage on the surface of bacterial cells.

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Savelieva, I. V., A. N. Kulichenko, V. N. Saveliev, D. A. Kovalev, O. V. Vasilieva, A. M. Zhirov, E. I. Eremenko et al. « MLVA-TYPING OF CLINICAL STAMPS OF GENETICALLY CHANGED VIBRIO CHOLERAE BIOTYPE EL TOR INSULATED IN RUSSIA AND UKRAINE IN THE PERIOD OF SEVENTH PANDEMIC CHOLERA ». Journal of microbiology epidemiology immunobiology, n^o 6 (28 décembre 2018) : 37–43. http://dx.doi.org/10.36233/0372-9311-2018-6-37-43.

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Aim. Conduct in a comparative aspect MLVA-typing of genetically altered cholera vibrio biovar El Tor, isolated from patients during the epidemic (1994) and outbreaks (1993, 1998) in Dagestan with isolates in Mariupol (Ukraine) in 1994-2011 in Moscow (2010, 2012), India (1964, 2006, 2007), Bangladesh 1991, 1994, 2001, 2004) and to establish Phylogenetic connections between strains of cholera vibrios isolated in different years in these territories, to ascertain the source of their drift. Materials and methods. MLVA-tyP-ing was carried out in PCR at 5 variable loci of 35 clinical strains of genetically modified Vibrio cholerae byotyPe El Tor. The obtained amPlicon was studied in the system of automatic caPillary electroPhoresis ExPerion («Bio Rad Laboratories», USA). For Phylogenetic analysis, along with MLVA-genotyPes, 35 strains of Vibrio cholerae from the Institute's collection used Published genotyPes of strains isolated in India, Bangladesh, Haiti. Results. The investigated strains of cholera vibrio are referred to 21 MLVA-tyPes, divided into 2 main clades and 1 seParate branch with clonal clusters and subclusters, each of which contains closely related strains of cholera vibrio genovariants having a different degree of Phylogenetic relationshiP - full or Partial identity of allelic Profiles of five variable loci. The sources of drift of genetically modified Vibrio cholerae byotyPe El Tor to Russia and Ukraine from disadvantaged cholera of India, Bangladesh, Azerbaijan and the countries of the Middle East have been established. Conclusion. The obtained data testify to the PolymorPhism of MLVA-tyPes of genetically altered strains of cholera vibrio of the biologist El Tor, evolved in different years and caused ePidemics or outbreaks of cholera in different territories during different time Periods of the course of the seventh cholera Pandemic, and also suggest the Polyclonal origin of the Vibrio cholerae biovar El Tor and the source of their drift to the territory of the Russian Federation and Ukraine.

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Ntema, V. M., N. Potgieter et T. G. Barnard. « Detection of Vibrio cholerae and Vibrio parahaemolyticus by molecular and culture based methods from source water to household container-stored water at the point-of-use in South African rural communities ». Water Science and Technology 61, n^o 12 (1 juin 2010) : 3091–101. http://dx.doi.org/10.2166/wst.2010.222.

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Detection methods for Vibrio cholerae and Vibrio parahaemolyticus which included the culture based approach with polymerase chain reaction (PCR) confirmation, PCR detection without enrichment and PCR with a pre-enrichment were developed and their performance evaluated. PCR assays targeted the SodB (V. cholerae species), Flae (V. parahaemolyticus species), 16S rRNA (Vibrio and Enterobacteriacea species) genes (Multiplex 1) and V. cholerae O1 and V. cholerae O139 rfb genes, ctxA (cholera toxin) gene and 16S rRNA gene (Multiplex 2). These methods were used to determine the occurrence of selected Vibrios in source water as well as in household container-stored water. The combination of filtration, enrichment and PCR method provided a sensitive and specific method for the detection of selected Vibrios in water samples. The PCR with a pre-enrichment method detected as few as 4–10 cfu/100 mL of selected Vibrios and PCR detection without the enrichment method detected as few as 40–100 cfu/100 mL of selected Vibrios. The inclusion of an enrichment period allows detection of culturable bacteria. As an application of the developed methods, V. cholerae and V. parahaemolyticus were detected in the source water used by the population and in the water-storage containers. The results indicate that Vibrio species in the containers could have originated from the source water and survive in biofilms inside the containers.

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Savelieva, I. V., S. N. Tikhonov, V. N. Saveliev, D. A. Kovalev, S. V. Pisarenko, E. S. Kotenev, B. V. Babenyshev, L. S. Zinich, N. N. Pidchenko et A. N. Kulichenko. « RETROSPECTIVE ANALYSIS OF BIOLOGICAL AND MOLECULAR-GENETIC PROPERTIES OF STRAINS - CAUSATIVE AGENTS OF CHOLERA - ISOLATED IN UKRAINE IN 1994 - 2011 ». Journal of microbiology epidemiology immunobiology, n^o 1 (28 février 2017) : 49–55. http://dx.doi.org/10.36233/0372-9311-2017-1-49-55.

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Aim. Retrospective analysis of biological and molecular-genetic properties of strains - causative agents of cholera - isolated in the period of epidemics in Ukraine in 1994 - 2011. Materials and methods. Phenotypic and molecular-genetic properties of 5 strains of cholera vibrios, biovar El Tor isolated from cholera patients and 4 strains from the environmental samples were studied using traditional bacteriological and genetic methods. Detection of DNA for toxigenicity genes and genes characteristic for El Tor and classic biovar were carried out by PCR method using reagent kits «AmpliSens- Vibrio cholerae FRT» and «.Vibrio cholerae ctxB-rstR-rstC genes, REF» (an experimental test system). Sequencing of genomes of 4 strains of causative agents of cholera was carried out in genetic analyzer Ion Torrent Personal Genome Machine. Results. Strains of cholera vibrios identified in Ukraine in 1994 and 2011 such as a typical toxigenic biovar El Tor (V cholerae 01, El Tor, Ogawa, Hly-, ctxA+, tcpA+) contain genes of the classic cholera vibrio in their genome and are genetically altered (hybrid) variants of cholera vibrio biovar El Tor producing enterotoxin CT1 and having increased virulence, that was clinically manifested in predominance of severe forms of cholera in Mariupol of Donetsk region in 2011. Genome sequences of the 4 studied strains were deposited into the international database DDBJ/EMBL/GenBank. Conclusion. The studied isolates were established to belong to a clade of strains associated with cholera outbreaks in Haiti and Asian continent, from where genetically altered strains of cholera vibrios biovar El Tor were introduced to Haiti in 2010, based on results of comparison of genomic sequences of the studied strains with genomes of V. cholera strains from the international database GenBank.

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Lomov, Yu M., N. R. Telesmanich, I. T. Andrusenko, E. A. Moskvitina et O. A. Areshina. « PROPERTIES OF VIBRIO CHOLERAE STRAINS ISOLATED IN ASIA AND THEIR RELATIONSHIP TO THE STRAINS CIRCULATING IN OTHER CONTINENTS DURING THE SEVENTH CHOLERA PANDEMIC ». Epidemiology and Infectious Diseases 17, n^o 1 (15 février 2012) : 39–45. http://dx.doi.org/10.17816/eid40654.

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The review deals with the properties of Vibrio cholerae (classical, El Tor, 0139, non-01/non-0139 strains) circulating worldwide during the seventh cholera pandemic. Particular attention is given to the variability in the cholera pathogen: the replacement of classical Vibrio cholerae by the El Tor biotype and subsequently the emergence of serogroup Vibrio cholerae 0139 and genetically altered El Tor Vibrio cholerae; the causes giving rise to these changes and spread of Vibrio cholera in the countries of the Asian continent. A large genetic variability found in Asian strains suggests that there is a real possibility of the emergence of new clones with new properties, including those with an epidemic potential. The Vibrio cholerae strains, that periodically appear in Asia and have an epidemic potential and new properties, spread over all continents, by causing cholera infection. The cholera pathogen adapts to new existence conditions in some cases, by altering some properties and, by having been rooted in a certain area, causes mainly sporadic cases of the disease. These Vibrio cholerae strains, unlike the Asian strains (the pathogens of the seventh pandemic), may be virulent, by preserving the virulence genes in the genome; however, they are, in most cases, non-endemic and unable to spread widely.

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Maurice Bilung, Lesley, Mintra Prommani Etriam, Ahmad Syatir Tahar, Teng Sing Tung et Kasing Apun. « Detection of Cholera Toxin-Producing Vibrio cholerae in Phytoplankton from Santubong and Samariang Estuaries ». Borneo Journal of Resource Science and Technology 9, n^o 1 (30 juin 2019) : 36–43. http://dx.doi.org/10.33736/bjrst.1584.2019.

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Many cholera outbreaks worldwide were associated with cholera toxin-producing Vibrio cholerae. The bacteria are ubiquitous in aquatic environment, whilst phytoplankton is associated with adaptation of the Vibrio species. This study was conducted to detect cholera toxin-producing Vibrio cholerae, and to determine association of the selected water physicochemical parameters with the number of the bacteria. In this study, a total of ten phytoplankton samples were collected at Santubong and Samariang Estuaries in Kuching, Sarawak. Water physicochemical parameters (temperature, pH and salinity) were recorded. Vibrio bacteria were cultivated on thiosulfate citrate bile-salts sucrose selective agar and analysed for cholera toxin-producing Vibrio cholerae using polymerase chain reaction by targeting ctxA gene that encodes for virulence cholera enterotoxin subunit A. The result revealed that a range of 1.0 × 107 – 8.0 × 107 CFU/ml of yellow colonies growing on the thiosulfate citrate bile-salts sucrose agars. Inversely, no samples were positive with cholera toxin-producing Vibrio cholerae. The physicochemical parameters at Samariang Estuary were more associated with the number of bacteria in the samples compared to Santubong Estuary.

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Mushayabasa, Steady, et Claver P. Bhunu. « Assessing the Impact of Increasing Antimicrobial Resistance of Vibrio cholerae on the Future Trends of Cholera Epidemic ». ISRN Biomathematics 2012 (4 décembre 2012) : 1–10. http://dx.doi.org/10.5402/2012/127492.

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Cholera, an acute intestinal infection caused by the bacterium Vibrio cholerae, remains a major public health problem in many parts of Africa, Asia, and Latin America. A mathematical model is developed, to assess the impact of increasing antimicrobial resistance of Vibrio cholerae on the future trends of the cholera epidemic. Equilibrium states of the model are determined and their stabilities have been examined. The impacts of increasing antimicrobial resistance of Vibrio cholerae on the future trends of cholera epidemic have been investigated through the reproductive number. Numerical results are provided to support analytical findings.

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WONG, HIN-CHUNG, WAN-RU SHIEH et YEONG-SHENG LEE. « Toxigenic Characterization of Vibrios Isolated from Foods Available in Taiwan ». Journal of Food Protection 56, n^o 11 (1 novembre 1993) : 980–82. http://dx.doi.org/10.4315/0362-028x-56.11.980.

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Several Vibrio species have been implicated in diarrheal diseases and wound infection, and some foods are important vehicles for these pathogens. A number of these vibrios isolated from food produced extracellular heat-labile or heat-stable hemolysin and cytotoxins, but only a few strains hybridized to nucleic acid probes of Shiga-like toxin, cholera toxin, or thermostable direct hemolysin. These vibrios also produced extracellular or cell-mediated mouse-lethal factors. The vibrios from foods may produce toxins not identical or related to the common toxins of Escherichia coli, Vibrio cholerae, or Vibrio parahaetnolyticus.

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Colwell, R. R., A. Huq, M. A. R. Chowdhury, B. Xu et P. R. Brayton. « Serogroup conversion of Vibrio cholerae ». Canadian Journal of Microbiology 41, n^o 10 (1 octobre 1995) : 946–50. http://dx.doi.org/10.1139/m95-131.

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Vibrio cholerae serogroup O1 can be detected in the environment in a viable but nonculturable form, whereas V. cholerae non-O1 cells can be readily cultured during interepidemic periods in geographical regions where cholera is endemic. In the present study, pure cultures of V. cholerae non-O1 cells contained 01 cells when examined by immune-fluorescence microscopy. Laboratory microcosms were used to examine the outgrowth of the O1 cells in cultures of non-O1 V. cholerae. One O1 cell per 106 non-O1 cells could be detected by direct fluorescent-monoclonal antibody staining but only after incubation of the non-O1 culture for 48 h. Individual O1 cells were not detected in cultures incubated less than 48 h. Hybridization study, using a polymerase chain reaction (PCR) amplified fragment of the O-antigen of V. cholerae O1 as a probe, revealed the existence of a homologous gene in a microcosm sample of V. cholerae non-O1 containing serogroup-converted cells. The mechanism by which O1 cells can occur in cultures of non-O1 V. cholerae most likely resulted from spontaneous mutation of gene(s) encoding the O-somatic properties and (or) chemical, physical, or biological changes in the environment inducing expression or repression of the controlling gene(s). These findings have important implications for the epidemiology of cholera and the environmental source(s) of toxin producing V. cholerae O1.Key words: serogroup conversion, Vibrio cholerae O1, Vibrio cholerae non-O1, cholera.

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Vanden Broeck, Davy, Caroline Horvath et Marc J. S. De Wolf. « Vibrio cholerae : Cholera toxin ». International Journal of Biochemistry & ; Cell Biology 39, n^o 10 (2007) : 1771–75. http://dx.doi.org/10.1016/j.biocel.2007.07.005.

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Nasreen, Tania, Nora A. S. Hussain, Mohammad Tarequl Islam, Fabini D. Orata, Paul C. Kirchberger, Rebecca J. Case, Munirul Alam, Stephanie K. Yanow et Yann F. Boucher. « Simultaneous Quantification of Vibrio metoecus and Vibrio cholerae with Its O1 Serogroup and Toxigenic Subpopulations in Environmental Reservoirs ». Pathogens 9, n^o 12 (16 décembre 2020) : 1053. http://dx.doi.org/10.3390/pathogens9121053.

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Vibrio metoecus is a recently described aquatic bacterium and opportunistic pathogen, closely related to and often coexisting with Vibrio cholerae. To study the relative abundance and population dynamics of both species in aquatic environments of cholera-endemic and cholera-free regions, we developed a multiplex qPCR assay allowing simultaneous quantification of total V. metoecus and V. cholerae (including toxigenic and O1 serogroup) cells. The presence of V. metoecus was restricted to samples from regions that are not endemic for cholera, where it was found at 20% of the abundance of V. cholerae. In this environment, non-toxigenic O1 serogroup V. cholerae represents almost one-fifth of the total V. cholerae population. In contrast, toxigenic O1 serogroup V. cholerae was also present in low abundance on the coast of cholera-endemic regions, but sustained in relatively high proportions throughout the year in inland waters. The majority of cells from both Vibrio species were recovered from particles rather than free-living, indicating a potential preference for attached versus planktonic lifestyles. This research further elucidates the population dynamics underpinning V. cholerae and its closest relative in cholera-endemic and non-endemic regions through culture-independent quantification from environmental samples.

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Tamplin, Mark L., Reema Jalali, Mohammed K. Ahmed et Rita R. Colwell. « Variation in epitopes of the B subunit of Vibrio cholerae non-O1 and Vibrio mimicus cholera toxins ». Canadian Journal of Microbiology 36, n^o 6 (1 juin 1990) : 409–13. http://dx.doi.org/10.1139/m90-071.

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Monoclonal antibodies reacting with the B subunit of Vibrio cholerae O1 strain 569B cholera toxin (CT-B) were used to identify unique and common epitopes of V. cholerae non-O1 and Vibrio mimicus CT-B. Vibrio cholerae non-O1 strains produced CT-B showing three monoclonal antibody reaction patterns (epitypes), which corresponded with epitypes described previously for V. cholerae O1 classical biotype CT-B (CT1), El Tor biotype CT-B (CT2), and a unique V. cholerae non-O1 CT-B (CT3), which lacked an epitope located in or near the GM1 ganglioside binding site of 569B CT-B. Vibrio mimicus CT-B was immunologically indistinguishable from 569B CT-B. These and previous results define six epitopes on 569B CT-B, and a fourth epitope in or near the GM1 ganglioside binding site. Key words: cholera toxin, epitopes, monoclonal antibodies.

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WONG, HIN-CHUNG, LI-LI CHEN et CHUNG-MING YU. « Occurrence of Vibrios in Frozen Seafoods and Survival of Psychrotrophic Vibrio cholerae in Broth and Shrimp Homogenate at Low Temperatures ». Journal of Food Protection 58, n^o 3 (1 mars 1995) : 263–67. http://dx.doi.org/10.4315/0362-028x-58.3.263.

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Pathogenic vibrios are important etiologic agents in tropical regions and have been frequently recovered from seafoods and aquacultured foods. In this study, commercially frozen seafoods including peeled shrimps and fish and shrimp dumplings were examined. Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio cholerae and Vibria fluvialis were recovered at 36.0%, 15.8%, 14.9% and 13.2%, respectively. A number of psychrotrophic vibrios were selected and their survival in tryptic soy broth (TSB) supplemented with 1% sodium chloride (NaCl) (TSBS medium) and shrimp homogenate at 4°C and −30°C were studied. Two psychrotrophic non-O1 V. cholerae (laboratory stocks no 128 and 129) survived well at these low temperatures. Counts decreased by about 1 log/ml in TSBS medium at 4°C for 6 days and 3 log/ml at −30°C for 3 days. Shrimp homogenate provided better protection than TSBS medium for psychrotrophic V. cholerae at −30°C. Survival of V. cholerae at low temperatures was further increased by the addition of 0.5% of heated pyrophosphate and metaphosphate, probably by decreasing the lethality of the cold injury to the cells. Measures should be taken to minimize the risk from pathogenic vibrios in frozen seafoods, especially if phosphates are used and psychrotrophic strains are present.

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Agustanty, Adelia, et Andre Budi. « POLA RESISTENCY OF VIBRIO CHOLERAE BACTERIA TO THE ANTIBIOTIC CIPROFLOXACIN AND TETRACYCLINE ». Journal Health & ; Science : Gorontalo Journal Health and Science Community 5, n^o 3 (8 avril 2022) : 73–78. http://dx.doi.org/10.35971/gojhes.v5i3.13611.

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Abstrak Diare merupakan kegiatan defekasi (buang air besar) yang biasanya berbentuk 1/2 padat atau cenderung lebih cair yang berlangsung lebih dari tiga kali sehari atau dalam waktu yang singkat, vibrio cholera adalah salah satu penyebabnya, bakteri ini merupakan bakteri gram negatif yang berbentuk koma galibnya masa inkubasi bakteri ini adalah 12-72 jam. Bakteri vibrio cholerae menyulut penyakit bakteri. Jenis penelitian ini adalah penelitian laboratorium eksperimental dengan menggunakan arsip sampel bakteri vibrio cholerae dan cakram antibiotik ciprofloxacin. Tujuan penelitian untuk mengetahui pola resistensi antibiotik ciprofloxacin terhadap bakteri vibrio cholerae. Populasi yang digunakan adalah isolate murni bakteri Vibrio cholera dan sampel yang digunakan adalah sediaan cakram dari antibiotik Ciprofloxacin dan Tetracycline. Nilai rata-rata (mm) selama 24 jam ciprofloxcacin : 37.425 , tetracycline : 24,175 Nilai rata-rata (mm) selam 48 jam ciprofloxacin : 29,875 tetracycline : 22,95 Berdasarkan hasil data dan gambar penelitian dapat di simpulkan bahwa diameter zona hambat atau zona bening dari biakan bakteri vibrio cholera yang terdapat dalam cawan petri dengan media MHA serta cakram antibiotik ciprofloxacin dan tetracycline menunjukkan bahwa bakteri uji masih sensitive terhadap kedua antibiotik uji yang dimana nilai rata-rata nya adalah 29,875 dan 22,95 mm dimana menurut standart CLSI (Clinical Laboratory Standards Institute), diameter zona hambat bakteri ≥ 17 mm, kategori intermediet apabila diameter zona hambat bakteri 14-16 mm, dan kategori resisten apabila diameter zona hambat bakteri yaitu ≤ 13mm. Kesimpulan bahwa biakan bakteri vibrio choleramasih sensitive terhadap kedua antibiotic ciprofloxacin dan tetracycline. Kata Kunci : Ciprofloxacin; Cholera; Diare; Tetracycline; Vibrio Cholerae. Abstract Diarrhea is a defecation activity (defecation) which is usually in the form of 1/2 solid or tends to be more liquid (watery) which lasts more than three times a day or in a short time, Vibrio cholera is one of the causes, this bacterium is a gram-negative bacterium that causes diarrhea. In the form of a comma, the incubation period for this bacterium is 12-72 hours. Vibrio cholerae bacteria cause bacterial disease. This type of research is an experimental laboratory study using archived samples of Vibrio cholerae bacteria and ciprofloxacin antibiotic discs. This study aims to determine the pattern of resistance to ciprofloxacin antibiotics against Vibrio cholerae bacteria. The population that will be used is pure isolate of Vibrio cholera bacteria and the sample used is disc preparation of the antibiotics Ciprofloxacin and Tetracycline. Average value (mm) for 24 hours ciprofloxcacin: 37.425, tetracycline: 24.175 Average value (mm) for 48 hours ciprofloxacin : 29.875 tetracycline : 22.95 Based on the results of the data and research images it can be concluded that the diameter of the inhibition zone or clear zone of the Vibrio cholera bacteria culture contained in petri dishes with MHA media and ciprofloxacin and tetracycline antibiotic discs showed that the test bacteria were still sensitive to the two test antibiotics where the average value was 29.875 and 22.95 mm where according to the CLSI (Clinical Laboratory Standards Institute) standard, the diameter of the bacterial inhibition zone was 17 mm, the intermediate category if the diameter of the bacterial inhibition zone was 14-16 mm, and the category of intermediate was 14-16 mm. resistant if the diameter of the bacterial inhibition zone is 13 mm. The conclusion is that the vibrio cholera bacteria culture is still sensitive to both ciprofloxacin and tetracycline antibiotics. Keywords: Ciprofloxacin ; Cholerae; Diarrhea ; Tetracycline ; Vibrio Cholerae.

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Larionova, L. V., R. V. Pisanov, D. I. Simakova, A. N. Narkevich et I. V. Arkhangel’skaya. « Polimeric Immunoglobulin Diagnosticum for Detection of Cholera Toxin and Assessing the Level of Its Production by Vibrios ». Problems of Particularly Dangerous Infections, n^o 4 (26 janvier 2022) : 84–89. http://dx.doi.org/10.21055/0370-1069-2021-4-84-89.

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A marker of the epidemic significance of Vibrio cholerae is their toxigenicity. Therefore, much attention is currently paid to the creation of diagnostic preparations for the detection of cholera toxin and assessment of the level of its production. The volumetric immunosuspension agglomeration reaction, carried out with the help of latex diagnosticums, is an analogue of the indirect hemagglutination reaction, an affordable and technically simple method, since it does not require special equipment and can be used when conducting research in the field. The aim of the study was to design a polymeric immunoglobulin diagnosticum for determining cholera toxin and the level of its production by vibrio strains. Materials and methods. Cholera toxin was obtained from the producer strain Vibrio cholerae Classical 569 B. Rabbit serum to the toxin was obtained according to the method selected by the authors. A polymeric diagnostic immunoglobulin antitoxic drug was obtained through sensitizing immunoglobulins from cholera antitoxic rabbit serum on the surface of polyacrolein microspheres with a size of (1±0.1) μm. Results and discussion. The analytical sensitivity of the developed diagnostic preparation with control cholera toxin is 100 ng/ml. It detects cholera toxin in toxigenic strains of Vibrio cholerae in a titer of 1:16 – 1:512, gives negative results with non-toxigenic strains of V. cholerae O1, V. Cholerae nonO1/nonO139, with samples of heterologous cultures, LPS preparations, liquid nutrient medium used for the cultivation of V. cholerae. Thus, a polymeric immunoglobulin diagnosticum has been constructed to detect and quantify the production of cholera toxin by vibrio strains, and its analytical sensitivity and specificity have been established.

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Mumbumbu, Albert M., Zacharie K. Tsongo, Etienne A. Shindano, Théophile B. Kabesha et Stanis O. Wembonyama. « Environmental and chemical determinants of contamination and survival of Vibrio cholerae in water sources in Bukavu in the Democratic Republic of the Congo ». Health and Environment 5, n^o 1 (22 juillet 2024) : 246–55. http://dx.doi.org/10.25082/he.2024.01.002.

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Introduction: Cholera is endemo-epidemic in Bukavu. The aim of the study was to assess the environmental determinants of permanent contamination of spring and well water and to evaluate some of the chemical factors responsible for the persistence of Vibrio cholerae in water consumed by cholera patients.Methods: Conducted in the Bukavu health district from September 2020 to September 2021, this was a cross-sectional. The potential of hydrogen (pH) of the water was evaluated before comparing it with the survival of Vibrio cholerae. A total of 641 latrines, 92 water sources, and wells were surveyed, with 298 samples analyzed in the laboratory.Results: Out of the 641 latrines surveyed, 367 (57%) were found to be unsanitary; 54 (59%) of the water sources and wells were also deemed unsanitary. In total, 57% of the water samples were found to contain Vibrio cholerae, with 90% exhibiting an alkaline pH, of which 54% tested positive for the bacteria. Conversely, 10% of the samples had an acidic pH, with 80% of those containing Vibrio cholerae. The pH levels of the water remained alkaline both during the epidemic (95%) and post-epidemic (84%), thereby favoring the survival of Vibrio cholerae serotypes Ogawa and Inaba in these water sources. An acidic pH was observed to increase the likelihood of Vibrio cholerae survival in these waters by a factor of 3.39.Conclusion: Spring and well water are consistently contaminated with Vibrio cholerae due to the unsanitary conditions of nearby latrines. The presence of Vibrio cholerae serotypes Inaba and Ogawa in these water sources is further influenced by the alkaline and acidic pH levels.

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LaRocque, Regina C., Bryan Krastins, Jason B. Harris, Lauren M. Lebrun, Kenneth C. Parker, Michael Chase, Edward T. Ryan, Firdausi Qadri, David Sarracino et Stephen B. Calderwood. « Proteomic Analysis of Vibrio cholerae in Human Stool ». Infection and Immunity 76, n^o 9 (30 juin 2008) : 4145–51. http://dx.doi.org/10.1128/iai.00585-08.

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ABSTRACT An effective vaccine for Vibrio cholerae is not yet available for use in the developing world, where the burden of cholera disease is highest. Characterizing the proteins that are expressed by V. cholerae in the human host environment may provide insight into the pathogenesis of cholera and assist with the development of an improved vaccine. We analyzed the V. cholerae proteins present in the stools of 32 patients with clinical cholera. The V. cholerae outer membrane porin, OmpU, was identified in all of the human stool samples, and many V. cholerae proteins were repeatedly identified in separate patient samples. The majority of V. cholerae proteins identified in human stool are involved in protein synthesis and energy metabolism. A number of proteins involved in the pathogenesis of cholera, including the A and B subunits of cholera toxin and the toxin-coregulated pilus, were identified in human stool. In a subset of stool specimens, we also assessed which in vivo expressed V. cholerae proteins were recognized uniquely by convalescent-phase as opposed to acute-phase serum from cholera patients. We identified a number of these in vivo expressed proteins as immunogenic during human infection. To our knowledge, this is the first characterization of the proteome of a pathogenic bacteria recovered from a natural host.

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LM, Leuva, Bhavsar TD, Rathod SD, Patel LR, Goswami AM, Rajput AH et Kadam MT. « Serotyping and Phage Typing of Vibrio cholerae Isolated AtTertiary Care Hospital, Ahmedabad, Gujarat ». BJKines National Journal of Basic & ; Applied Sciences 15, n^o 02 (10 décembre 2023) : 5–10. http://dx.doi.org/10.56018/20231201.

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Introduction: Cholera continues to be a growing concern in most developing countries. Cholera is an acute diarrheal disease endemic in India. Yet there are few reliable population-based estimates of laboratory-confirmed cholera in endemic areas around the world. The aim of this hospital-based study was to isolate and serogrouping of Vibrio cholerae in patients with diarrhea at tertiary care hospital, Ahmedabad during January 2021 to July 2022. Material & Methods: A retrospective study involving cases of acute watery diarrhea was done during January 2021 to July 2022. All stool samples from suspected cases were tested for Vibrio cholerae by standard microbiological procedures. Out of total 1294 stool samples Vibrio cholerae were isolated in 179 samples and sent to the NICED (National Institute of Cholera and Enteric Diseases) for serotyping and phage typing. Results: In present study rate of isolates of V. cholerae was 13.83 % (179 out of 1294 cases). V. cholerae O1 serotype Ogawa (78.77%) belonging to phage type 27 (54.74%) was the most common in the cases of acute diarrhea in present study. Conclusion: The present study identified serotype Ogawa and phage type 27 as the most dominant type and was found continuous in circulation throughout the study period. Phage typing is still an internationally recognized method of choice for characterizing circulating strains. This knowledge will be helpful to design a novel strategy to manage future cholera outbreaks. Keywords: Cholera, Vibrio cholerae, Serotyping, Phage typing

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Huq, Anwar, R. Bradley Sack, Azhar Nizam, Ira M. Longini, G. Balakrish Nair, Afsar Ali, J. Glenn Morris et al. « Critical Factors Influencing the Occurrence of Vibrio cholerae in the Environment of Bangladesh ». Applied and Environmental Microbiology 71, n^o 8 (août 2005) : 4645–54. http://dx.doi.org/10.1128/aem.71.8.4645-4654.2005.

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ABSTRACT The occurrence of outbreaks of cholera in Africa in 1970 and in Latin America in 1991, mainly in coastal communities, and the appearance of the new serotype Vibrio cholerae O139 in India and subsequently in Bangladesh have stimulated efforts to understand environmental factors influencing the growth and geographic distribution of epidemic Vibrio cholerae serotypes. Because of the severity of recent epidemics, cholera is now being considered by some infectious disease investigators as a “reemerging” disease, prompting new work on the ecology of vibrios. Epidemiological and ecological surveillance for cholera has been under way in four rural, geographically separated locations in Bangladesh for the past 4 years, during which both clinical and environmental samples were collected at biweekly intervals. The clinical epidemiology portion of the research has been published (Sack et al., J. Infect. Dis. 187:96-101, 2003). The results of environmental sampling and analysis of the environmental and clinical data have revealed significant correlations of water temperature, water depth, rainfall, conductivity, and copepod counts with the occurrence of cholera toxin-producing bacteria (presumably V. cholerae). The lag periods between increases or decreases in units of factors, such as temperature and salinity, and occurrence of cholera correlate with biological parameters, e.g., plankton population blooms. The new information on the ecology of V. cholerae is proving useful in developing environmental models for the prediction of cholera epidemics.

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Kadhim, Suadad, et Dhuha Saleh. « DETECTION OF SOME BACTERIAL CAUSES OF WATERY DIARRHEA IN THE PROVINCE OF BAGHDAD AND SOME NORTHERN GOVERNORATES WITH ASTUDY OF PATHOLOGICAL EFFECTS ». Iraqi Journal of Science 53, n^o 3 (20 mars 2024) : 536–43. http://dx.doi.org/10.24996/iraqijournalofscience.v53i3.12753.

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The present study Investigate the study on the causes of diarrhea epidemic in the province of Baghdad and some northern governorates since been collected 140 stool samples of water of different ages for the period from the beginning of the month of October 2007 to the end of August 2008, after culture ,microscopic biochemical testing diagnosed (113) bacterial isolates was among them ( 66) isolation rate of (% 47.14) only belonging to Vibrios cholera, Vibrio cholerae are divided by (58) in a rate (% 87.87) and returned to the pattern under serum Inaba, and (5) isolates, a rate (% 7.57) and returned to the pattern under serum Ogawa, all belonging to the pattern of bio-El-Tor and three isolates by (4.54%) belonging to non-cholera vibrios NAG The study showed the presence of 10 bacterial isolates were similar in most characteristics of the cholera bacteria, vibrios with some of the differences that emerged when Biochemical tests, which gave a negative result of the examination and testing of cholera red stitching and nitrate reduction Histopathological study using experimental animals indicate similarity in pathogenesis of V. cholerae and vibrio like bacteria ,both cause congested spleen and liver and desquamation in the intestinal villi

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Ibarra Trujillo, Jimmy, Alvaro Delgado et Débora Alvarado. « Vibrios no Epidémicos y Vibrio cholerae O1 Asociados a Enfermedad Diarreica Aguda. Evento Climatológico. "El Niño" - 1998. Hospital Nacional Dos de Mayo ». Anales de la Facultad de Medicina 60, n^o 4 (7 avril 2014) : 251. http://dx.doi.org/10.15381/anales.v60i4.4382.

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OBJETIVOS: Aislar e identificar Vibrio cholerae O1 y especies de vibrios no epidémicos asociados a casos de enfermedad diarreica aguda (EDA) durante 1998, dentro del evento climatológico "El Niño" Oscilación del Sur (ENOS). MATERIALES Y MÉTODOS: Durante los meses de verano de 1998 se realizó 70 coprocultivos de pacientes con EDA admitidos en la sala de emergencia del Hospital Nacional Dos de Mayo de Lima. Se estudió colonias aisladas en Agar TCBS. Los aislados fueron sometidos a pruebas bioquímicas y serológicas para la identificación de Vibrio cholerae O1. La identificación de vibrios no epidémicos y otros vibrios patogénicos se realizó tomando en consideración las características descritas en el Manual de Sistemática Bacteriana de Bergey (1994). RESULTADOS: Los resultados indican que el mayor numero de casos estudiados estuvieron asociados a Vibrio cholerae O1 como agente etiológico único (64,3%) o relacionados a otras especies de Vibrio (4,2%). Se relata 2 casos (2,9%) que involucraron a V. vulnificus y 3 (4,3%) a V. parahaemolyticus como agentes etiológicos de diarrea aguda. CONCLUSIONES: La asociación de Vibrio cholerae O1 con otras especies de vibrios no epidémicos permitiría establecer una relación directa entre las infecciones diarreicas estudiadas y el ENOS.

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Kitaoka, Maya, Sarah T. Miyata, Daniel Unterweger et Stefan Pukatzki. « Antibiotic resistance mechanisms of Vibrio cholerae ». Journal of Medical Microbiology 60, n^o 4 (1 avril 2011) : 397–407. http://dx.doi.org/10.1099/jmm.0.023051-0.

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As the causative agent of cholera, the bacterium Vibrio cholerae represents an enormous public health burden, especially in developing countries around the world. Cholera is a self-limiting illness; however, antibiotics are commonly administered as part of the treatment regimen. Here we review the initial identification and subsequent evolution of antibiotic-resistant strains of V. cholerae. Antibiotic resistance mechanisms, including efflux pumps, spontaneous chromosomal mutation, conjugative plasmids, SXT elements and integrons, are also discussed. Numerous multidrug-resistant strains of V. cholerae have been isolated from both clinical and environmental settings, indicating that antibiotic use has to be restricted and alternative methods for treating cholera have to be implemented.

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A.A., Michael, et Adenike B.A. « Prevalence of Vibrio Cholerae and Vibrio Species from Different Sources in Bayelsa State, Nigeria ». African Journal of Biology and Medical Research 4, n^o 2 (3 mai 2021) : 38–50. http://dx.doi.org/10.52589/ajbmr-g5st3zwt.

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The distribution of Vibrio cholerae and non-cholera Vibrio species from different sources from five localities in Bayelsa State, Nigeria was investigated in this study. A total of 44 stool samples, 22 freshwater samples, 60 brackish water samples and 64 seafood samples (crabs, shrimps and fishes) were collected from January to April, 2019 for the purpose of V. cholerae prevalence study. Samples were transported to the laboratory using Car-Blair’s medium. This was followed by samples enrichment in 1% alkaline peptone water and pour plating on thiosulphate citrate bile-salt sucrose (TCBS) agar. Characteristic yellow colonies were subjected to further biochemical and physiological characterization to further identify V. cholerae. Antibiotics susceptibility patterns for isolated V. cholerae strains were investigated. Furthermore, water samples (fresh and brackish) and seafood samples were collected on a monthly basis to ascertain the effect of seasons (dry and wet months) on the distribution of Vibrio spp. A total of 16 (36.36%) stools samples were positive for V. cholerae. In addition, 12 (54.55%) of freshwater samples, 28 (46.67%) of brackish water samples and 22 (34.38%) of seafood samples were contaminated with V. cholerae. The monthly mean values of Vibrio spp. from environmental sources showed statistically significant difference (P<0.05) between the dry months (low rainfall) and wet months (frequent rainfall). Higher average values were observed during the dry months. The result of the antibiotics sensitivity test showed all V. cholerae strains were susceptible to ciprofloxacin, ofloxacin and pefloxacin while varying degree sensitivities were observed in tetracycline and augmentin. Cholera and other non-cholera Vibrio spp gastrointestinal infections are still a major concern to the health of the public. Local and regional governments should enforce and promote the need for personal and communal hygienic practices.

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Sabbah, Majeed Arsheed, Bilal Kamil Sulaiman, Kifah, A. Jasim et Mohammod M. Farhan. « Detection of toxigenic Vibrio cholerae by PCR ». Journal of Biotechnology Research Center 5, n^o 1 (1 janvier 2011) : 18–21. http://dx.doi.org/10.24126/jobrc.2011.5.1.139.

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holera toxin (CT) is a major virulence factor of V. cholerae causing water diarrhea. The detection of CT-producing V. cholerae using conventional culture-, biochemical- and immunological-based assays is time-consuming, laborious, and requiring more than three days perform. In this work a specific primers for ctxB gene were used for detection of V. cholera in water samples. Few colonies of V. cholera were suspended in water and used as a template in PCR reaction for the detection of ctxB gene. The 391-bp sequence of a gene that codes for the cholera toxin B subunit was amplified by PCR. Direct use of V. cholerae pure culture for PCR replaces the need for DNA extraction or boiling. Increase the concentration of MgCl2 enhances the efficiency of amplification. The specificity of the assay was determined to be specific for V. cholerae but not for, vibrio related bacteria, E. coli, Non-Agglutinable (NAG) V. cholerae, and Aeromonas sp.

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Cheneke, Kumama Regassa, Koya Purnachandra Rao et Geremew Kenassa Edessa. « Application of a New Generalized Fractional Derivative and Rank of Control Measures on Cholera Transmission Dynamics ». International Journal of Mathematics and Mathematical Sciences 2021 (2 novembre 2021) : 1–9. http://dx.doi.org/10.1155/2021/2104051.

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In this study, the mathematical model of the cholera epidemic is formulated and analyzed to show the impact of Vibrio cholerae in reserved freshwater. Moreover, the results obtained from applying the new fractional derivative method show that, as the order of the fractional derivative increases, cholera-preventing behaviors also increase. Also, the finding of our study shows that the dynamics of Vibrio cholerae can be controlled if continuous treatment is applied in reserved freshwater used for drinking purposes so that the intrinsic growth rate of Vibrio cholerae in water is less than the natural death of Vibrio cholerae. We have applied the stability theory of differential equations and proved that the disease-free equilibrium is asymptotically stable if R 0 < 1 , and the intrinsic growth rate of the Vibrio cholerae bacterium population is less than its natural death rate. The center manifold theory is applied to show the existence of forward bifurcation at the point R 0 = 1 and the local stability of endemic equilibrium if R 0 > 1 . Furthermore, the performed numerical simulation results show that, as the rank of control measures applied increases from no control, weak control, and strong control measures, the recovered individuals are 55.02, 67.47, and 674.7, respectively. Numerical simulations are plotted using MATLAB software package.

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Alam, Munirul, Marzia Sultana, G. Balakrish Nair, R. Bradley Sack, David A. Sack, A. K. Siddique, Afsar Ali, Anwar Huq et Rita R. Colwell. « Toxigenic Vibrio cholerae in the Aquatic Environment of Mathbaria, Bangladesh ». Applied and Environmental Microbiology 72, n^o 4 (avril 2006) : 2849–55. http://dx.doi.org/10.1128/aem.72.4.2849-2855.2006.

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ABSTRACT Toxigenic Vibrio cholerae, rarely isolated from the aquatic environment between cholera epidemics, can be detected in what is now understood to be a dormant stage, i.e., viable but nonculturable when standard bacteriological methods are used. In the research reported here, biofilms have proved to be a source of culturable V. cholerae, even in nonepidemic periods. Biweekly environmental surveillance for V. cholerae was carried out in Mathbaria, an area of cholera endemicity adjacent to the Bay of Bengal, with the focus on V. cholerae O1 and O139 Bengal. A total of 297 samples of water, phytoplankton, and zooplankton were collected between March and December 2004, yielding eight V. cholerae O1 and four O139 Bengal isolates. A combination of culture methods, multiplex-PCR, and direct fluorescent antibody (DFA) counting revealed the Mathbaria aquatic environment to be a reservoir for V. cholerae O1 and O139 Bengal. DFA results showed significant clumping of the bacteria during the interepidemic period for cholera, and the fluorescent micrographs revealed large numbers of V. cholerae O1 in thin films of exopolysaccharides (biofilm). A similar clumping of V. cholerae O1 was also observed in samples collected from Matlab, Bangladesh, where cholera also is endemic. Thus, the results of the study provided in situ evidence for V. cholerae O1 and O139 in the aquatic environment, predominantly as viable but nonculturable cells and culturable cells in biofilm consortia. The biofilm community is concluded to be an additional reservoir of cholera bacteria in the aquatic environment between seasonal epidemics of cholera in Bangladesh.

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Rabiu, Murtala, Kumurya A.S., Abdulkadir Bashir et Aliyu I.A. « Systematic Review on the Antibacterial Resistance of Vibrio Cholerae ». UMYU Scientifica 1, n^o 1 (30 septembre 2022) : 60–66. http://dx.doi.org/10.56919/usci.1122.009.

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Background: Vibrio cholerae is the causative agent of cholera illness. Antibacterial resistance of V. cholerae is frequently experienced due to the environmental pressure from human and animal overuse and misuse of antibacterials. Among such antibacterials include Tetracycline, Chloramphenicol, Furazolidone, Ampicillin, and Trimethoprim-Cotrimoxazole as used against V. cholerae O1, O139 and non O1, O139 strains. Objectives: This systematic review was aimed at providing an overview of Antibacterial resistant strains of Vibrio cholerae in terms of year, location and factors responsible for the resistance. Material and Method: Systematic Electronic database search of PubMed (NCBI) by means of the key terms MeSH “Antimicrobial resistance of Vibrio cholerae” between the period of January 2000 to October 2018 was used. Results: From the findings it showed that many factors are responsible for Antibacterial resistance of Vibrio cholerae which include genetic composition, mutation, enzymes. Also V. cholerae, both O1, O139, environmental and non O1/ non O139 such as V. anginiloticus, paraheamolytcus were incriminated in transferring resistance genes from one another. Antimimicrobial Susceptibility Testing phenotypic and Polymerase Chain Reaction (PCR) molecular procedure were employed in detecting the resistance and equally the use of Global Antimicrobial Surveillance System (GLASS) and Centre for Disease control (CDC) AR threat report 2019 was used successfully in the management of Vibrio cholerae epidemic. Conclusions: Drug-resistant Vibrio cholarae is a problem that needs to be dealt with as soon as possible

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Kumar Shrestha, Bijay, et Jenish Shakya. « Simple method devised for rapid isolation and identification of Vibrio cholerae from water resources of Sunsari District, Nepal ». Nepal Journal of Biotechnology 9, n^o 2 (31 décembre 2021) : 33–38. http://dx.doi.org/10.54796/njb.v9i2.41913.

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Cholera is a gastrointestinal disease caused by pathogenic strain of Vibrio cholerae, the disease clinically manifested by rice-water diarrhea, nausea and vomiting. This study aimed to study the incidence of Vibrio species and employ simple method for rapid detection of Vibrio cholerae from water samples of Sunsari, Nepal. Identification of V. cholerae through biochemical tests requires extensive labor and costs. In resource limited laboratories, isolation and identification of V. cholerae often becomes difficult. Therefore, this study also aimed for selecting scope of this methodology as a scientific outcome for rapid isolation and identification of Vibrio cholerae. A total of 100 water samples were collected from Sunsari district in which 25 samples were collected from sewage, 25 from pond, 25 from tap and 25 from tube well. The samples of collected water were sent to the microbiology laboratory of Central Campus of Technology maintained in ice cold box and were enriched in Alkaline Peptone water and selectively isolated from TCBS agar and NA agar without NaCl. Pathogens were isolated and identified by conventional microbiological techniques. Out of 100 water samples collected, sucrose fermenting Vibrio species were isolated only from 16 water samples. Further the selective isolation of V. cholerae from nutrient agar without NaCl isolated 6 isolates from sewage samples and 3 isolates from pond samples. The distribution of Vibrio cholera in the water sample was found to be 9%, distribution of V. alginolyticus was found to be 4% and distribution of V. fluvialis was found to be 3%. In this study, non-sucrose fermenting Vibrio species were not isolated from the water samples. However, sucrose fermenting Vibrio species was obtained with yellow pigmentation in TCBS agar medium. The yellow pigmented colonies of Vibrio isolates recovered from TCBS and even from Nutrient Agar devoid of sodium chloride provided sufficient evidence of V. cholerae after series of other biochemical tests. This study concludes that yellow colonies (sucrose-fermenting) of Vibrio from TCBS agar medium that can grow on nutrient agar without added NaCl and which exhibit a positive oxidase reaction can be confidently identified as presumptive V. cholerae. In resource-constrained environments, this simple method can reduce the labor cost, chemicals and time-consuming procedure of performing multiple biochemical and molecular assays for identification.

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KWAN, L. C., D. K. F. CHEUNG et K. M. KAM. « Peak occurrences of ciguatera fish poisoning precede cholera outbreaks in Hong Kong ». Epidemiology and Infection 131, n^o 1 (août 2003) : 621–26. http://dx.doi.org/10.1017/s0950268803008665.

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Occurrences of ciguatera fish poisoning (CFP) and Vibrio cholerae infected patients in Hong Kong were reviewed for the 13-year period 1989–2001. Peak activity of CFP preceded peak activity of cholera in nine of the years except in 4 years (1990, 1991, 1992, 1996) where it was observed that the total number of cholera cases were all less than or equal to five per year (P<0·05). Average time interval was 2·4 months between peaks of CFP and Vibrio cholerae outbreaks. Findings suggested that the factors that affect cholera and ciguatera occurrences may not be operating in some years but when they are operating, they will affect both cholera and CFP. CFP peaks have consistently occurred before Vibrio cholerae peaks in our locality so much so that the occurrence of the latter can now be almost accurately predicted since 1998. CFP peaks served as an early warning for public measures to be in place before occurrence of cholera outbreaks.

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Vodop’yanov, Aleksey S., S. O. Vodop’yanov, I. P. Oleynikov et B. N. Mishan’kin. « INDEL-GENOTYPING OF VIBRIO CHOLERAE STRAINS ». Epidemiology and Infectious Diseases 22, n^o 4 (15 août 2017) : 195–200. http://dx.doi.org/10.17816/eid40978.

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The aim of this work was to genotype Vibrio cholerae strains, based on 9 INDEL-markers. We identified 26 genotypes in 223 strains studied. Based on the cluster analysis, all genotypes were grouped into 8 clusters. A geographic attachment to specific regions was characteristic for some of the clusters. Toxigenic strains formed a separate cluster and have genotypes different from atoxigenic strains. All strains V cholerae O1 Eltor, isolated from 1929 to 2014, had an identical genotype, different from the genotypes of V. cholerae O1 classical and V. cholerae O139. A loss of cholera toxin gene was shown to fail to give rise in the alteration of INDEL-genotype. This allows us recommend this genotyping method for the identification strains that had a cholera toxin gene in the past. Under annual isolation of strains of V. cholerae from environmental objects, their population was established to be particular due to a high level of genetic diversity. This makes it possible to propose the use of the diversity index as one of the criteria for the assessment of epidemiological risk.

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Sundar, Kothandapani. « Quorum Sensing Based Drug Screening Against Vibrio Cholerae ». Journal of Microbes and Research 1, n^o 1 (28 novembre 2022) : 01–05. http://dx.doi.org/10.58489/2836-2187/001.

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The QS method is a means of bacterial cell-to-cell communication, which uses extracellular signal molecules called autoinducers to transmit information between cells.Bacteria can use QS to collaborate on tasks. The pathogen Vibrio cholerae uses QS to inhibit the development of virulence factors and the formation of biofilms. Cholera is caused by the Gram-negative, curved bacteria Vibrio cholerae (Clemens et al., 2017). There are also a number of virulence components produced by this disease, including cholera hemolysin (CH), toxin-co-regulated pilus (TCP), flagellum, etc. By constraining the target protein, HapR, with adequate bioactive compounds, the pathogenic activity of in vibrio cholerae can be suppressed.Bioactive substances from various natural food sources were chosen and analysed for their quorum quenching effect against HapR protein utilising bioinformatics methods. The in-silico analysis produced notable results for thirteen of the 25 substances evaluated, with the best docking score. These chemicals could be employed for QSI-based therapeutics against vibrio cholerae infections and could be suggested for in vitro and in vivo investigations.

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Ehara, Masahiko, Mamoru Iwami, Yoshio Ichinose, Toshiya Hirayama, M. John Albert, R. Bradley Sack et Shoichi Shimodori. « Induction of Fimbriated Vibrio cholerae O139 ». Clinical Diagnostic Laboratory Immunology 5, n^o 1 (1 janvier 1998) : 65–69. http://dx.doi.org/10.1128/cdli.5.1.65-69.1998.

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ABSTRACT Several fimbriated phases of Vibrio cholerae O139 strains were selectively induced and compared immunologically and biochemically with those of V. cholerae O1. Fimbrial antigens were detected on the surfaces of vibrio cells colonizing the epithelial cells of a rabbit small intestine. Convalescent-phase sera from six individuals infected with V. cholerae O139 revealed the development of antibody against the fimbrillin. These findings suggest that the fimbriae of V. cholerae O1 and O139 are expressed in vivo during infection and that consideration must be given to the use of fimbrial antigens as components of vaccines against cholera.

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Gancz, Hanan, Orly Niderman-Meyer, Meir Broza, Yechezkel Kashi et Eyal Shimoni. « Adhesion of Vibrio cholerae to Granular Starches ». Applied and Environmental Microbiology 71, n^o 8 (août 2005) : 4850–55. http://dx.doi.org/10.1128/aem.71.8.4850-4855.2005.

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ABSTRACT Cholera is a severe diarrheal disease caused by specific serogroups of Vibrio cholerae that are pathogenic to humans. Cholera can become epidemic and deadly without adequate medical care. Appropriate rehydration therapy can reduce the mortality rate from as much as 50% of the affected individuals to <1%. Thus, oral rehydration therapy (ORT) is an important measure in the treatment of this disease. To further reduce the symptoms associated with cholera, improvements in oral rehydration solution (ORS) by starch incorporation were suggested. Here, we report that V. cholerae adheres to starch granules incorporated in ORS. Adhesion of 98% of the cells was observed within 2 min when cornstarch granules were used. Other starches showed varied adhesion rates, indicating that starch source and composition play an important role in the interaction of V. cholerae and starch granules. Sugars metabolized by V. cholerae showed a repressive effect on the adhesion process. The possible mechanisms involved are discussed. Comparing V. cholerae adhesion with the adhesion of other pathogens suggests the involvement of starch degradation capabilities. This adhesion to granular starch can be used to improve ORT.

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Tyurina, A. V., N. E. Gaevskaya, I. A. Ivanova, A. V. Filippenko, N. D. Omel’chenko, A. A. Trufanova, M. P. Pogozhova, A. O. Anoprienko, Yu V. Sizova et N. I. Pasyukova. « Assessment of the Effectiveness of Cholera Bacteriophages for Prevention of Experimental Cholera ». Problems of Particularly Dangerous Infections, n^o 2 (3 juillet 2024) : 193–95. http://dx.doi.org/10.21055/0370-1069-2024-2-193-195.

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The possibility of cholera importation into our country and the increase in the number of Vibrio cholerae strains that are resistant to antibacterial agents necessitate the development of alternative therapeutic and prophylactic biological products based on bacteriophages.The aim of the work was to study the effectiveness of application of cholera bacteriophages for the prevention of experimental cholera.Materials and methods. The work involved cholera bacteriophages Rostov-M3, Rostov-13, active against cholera vibrios of the O1 serogroup; and FB1, which has lytic activity against the O139 serogroup. The effectiveness of cholera prevention was assessed using a model of an isolated loop of the small intestine in an adult rabbit.Results and discussion. The use of Rostov-M3 and Rostov-13 for five and especially seven days before infection with virulent strains of V. cholerae O1 serogroup prevents the development of infection in the small intestine of experimental animals. Bacteriophage FB1 did not have that ability against V. cholerae O139. These studies indicate the effectiveness of using phages Rostov-M3 and Rostov-13 for the prevention of experimental cholera caused by V. cholerae O1 serogroup.

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Naser, Iftekhar Bin, Tushar Ahmed Shishir, Shah Nayeem Faruque, M. Mozammel Hoque, Anamul Hasan et Shah M. Faruque. « Environmental prevalence of toxigenic Vibrio cholerae O1 in Bangladesh coincides with V. cholerae non-O1 non-O139 genetic variants which overproduce autoinducer-2 ». PLOS ONE 16, n^o 7 (2 juillet 2021) : e0254068. http://dx.doi.org/10.1371/journal.pone.0254068.

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Prevalence of toxigenic Vibrio cholerae O1 in aquatic reservoirs in Bangladesh apparently increases coinciding with the occurrence of seasonal cholera epidemics. In between epidemics, these bacteria persist in water mostly as dormant cells, known as viable but non-culturable cells (VBNC), or conditionally viable environmental cells (CVEC), that fail to grow in routine culture. CVEC resuscitate to active cells when enriched in culture medium supplemented with quorum sensing autoinducers CAI-1 or AI-2 which are signal molecules that regulate gene expression dependent on cell density. V. cholerae O1 mutant strains with inactivated cqsS gene encoding the CAI-1 receptor has been shown to overproduce AI-2 that enhance CVEC resuscitation in water samples. Since V. cholerae non-O1 non-O139 (non-cholera-vibrios) are abundant in aquatic ecosystems, we identified and characterized naturally occurring variant strains of V. cholerae non-O1 non-O139 which overproduce AI-2, and monitored their co-occurrence with V. cholerae O1 in water samples. The nucleotide sequence and predicted protein products of the cqsS gene carried by AI-2 overproducing variant strains showed divergence from that of typical V. cholerae O1 or non-O1 strains, and their culture supernatants enhanced resuscitation of CVEC in water samples. Furthermore, prevalence of V. cholerae O1 in the aquatic environment was found to coincide with an increase in AI-2 overproducing non-O1 non-O139 strains. These results suggest a possible role of non-cholera vibrios in the environmental biology of the cholera pathogen, in which non-O1 non-O139 variant strains overproducing AI-2 presumably contribute in resuscitation of the latent pathogen, leading to seasonal cholera epidemics. Importance. Toxigenic Vibrio cholerae which causes seasonal epidemics of cholera persists in aquatic reservoirs in endemic areas. The bacteria mostly exist in a dormant state during inter-epidemic periods, but periodically resuscitate to the active form. The resuscitation is enhanced by signal molecules called autoinducers (AIs). Toxigenic V. cholerae can be recovered from water samples that normally test negative for the organism in conventional culture, by supplementing the culture medium with exogenous AIs. V. cholerae belonging to the non-O1 non-O139 serogroups which do not cause cholera are also abundant in natural waters, and they are capable of producing AIs. In this study we characterized V. cholerae non-O1 non-O139 variant strains which overproduce an autoinducer called AI-2, and found that the abundance of the cholera pathogen in aquatic reservoirs correlates with an increase in the AI-2 overproducing strains. Our results suggest a probable role of these variant strains in the environmental biology and epidemiology of toxigenic V. cholerae, and may lead to novel means for surveillance, prevention and control of cholera.

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Parveen, Salina, Samuel R. Farrah, Celia Gonzalez-Bonilla, Altagracia V. Zamudio et Mark L. Tamplin. « Characterization of a clinicalVibrio choleraeO139 isolate from Mexico ». Canadian Journal of Microbiology 49, n^o 1 (1 janvier 2003) : 65–70. http://dx.doi.org/10.1139/w03-004.

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Pathogenic strains of Vibrio cholerae O139 possess the cholera toxin A subunit (ctxA) gene as well as the gene for toxin co-regulated pili (tcpA). We report the isolation of a ctxA-negative, tcpA-negative V. cholerae O139 strain (INDRE1) from a patient in Mexico diagnosed with gastrointestinal illness. Certain phenotypic characteristics of this strain were identical to those of V. cholerae O1 biotype El Tor. Unlike ctxA-positive V. cholerae O139 strains, this strain was sensitive to a wide panel of antibiotics, including ampicillin, chloramphenicol, ciprofloxacin, gentamicin, furazolidone, nalidixic acid, nitrofurantoin, tetracycline, trimethoprim-sulfamethoxazole, and streptomycin, but was resistant to polymyxin B. Ribotype and pulsed-field gel electrophoresis profiles of INDRE1 differed from those of ctxA-positive V. cholerae O139 and other V. cholerae strains. Phenotypic characteristics of the Mexico strain were similar to those reported for V. cholerae O139 isolates from Argentina and Sri Lanka.Key words: Vibrio cholerae O139, cholera toxin, ctxA, tcpA.

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Runft, Donna L., Kristie C. Mitchell, Basel H. Abuaita, Jonathan P. Allen, Sarah Bajer, Kevin Ginsburg, Melody N. Neely et Jeffrey H. Withey. « Zebrafish as a Natural Host Model for Vibrio cholerae Colonization and Transmission ». Applied and Environmental Microbiology 80, n^o 5 (27 décembre 2013) : 1710–17. http://dx.doi.org/10.1128/aem.03580-13.

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ABSTRACTThe human diarrheal disease cholera is caused by the aquatic bacteriumVibrio cholerae.V. choleraein the environment is associated with several varieties of aquatic life, including insect egg masses, shellfish, and vertebrate fish. Here we describe a novel animal model forV. cholerae, the zebrafish. PandemicV. choleraestrains specifically colonize the zebrafish intestinal tract after exposure in water with no manipulation of the animal required. Colonization occurs in close contact with the intestinal epithelium and mimics colonization observed in mammals. Zebrafish that are colonized byV. choleraetransmit the bacteria to naive fish, which then become colonized. Striking differences in colonization betweenV. choleraeclassical and El Tor biotypes were apparent. The zebrafish natural habitat in Asia heavily overlaps areas where cholera is endemic, suggesting that zebrafish andV. choleraeevolved in close contact with each other. Thus, the zebrafish provides a natural host model for the study ofV. choleraecolonization, transmission, and environmental survival.

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Levchenkо, D. A., V. D. Kruglikov, N. E. Gaevskaya, A. S. Vodop’yanov et N. V. Nepomnyashchaya. « Pheno- and Genotypical Features of Non-Toxigenic Strains of Cholera Vibrios of Different Origins, Isolated in the Territory of Russia ». Problems of Particularly Dangerous Infections, n^o 3 (22 octobre 2020) : 89–96. http://dx.doi.org/10.21055/0370-1069-2020-3-89-96.

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Aim. Analysis of the phenotypic characteristics and identification of peculiarities of the genotypic organization in non-toxigenic strains of cholera vibrios having different origin, isolated in Russia. Materials and methods. A sample of 548 non-toxigenic strains obtained using the author’s updated GIS “Cholera 1989–2014” was used. PCR genotyping was carried out in accordance with the patented “Method for the identification of non-toxigenic strains of cholera vibrio O1 serogroup using PCR to isolate genetic determinants.” Cluster analysis was performed applying the UPGMA method. The dendrogram was constructed using MEGA 5 software package.Results and discussion. Representative cultural-morphological, serological and biochemical properties of V. cholerae strains have been specified. The variability of the studied strains on the basis of phagolizability has been revealed. Unique phage-types not previously encountered in Russia have been identified. The population of non-toxigenic strains of cholera vibrio O139 serogroup is genetically homogeneous in contrast to V. cholerae O1 El Tor isolates and has identical PCR genotypes. The universality of the PCR genotyping by 14 target genes has been shown to differentiate the studied strains of V. cholerae O1 and O139, as well as to identify disparities among O139 strains isolated in different geographical regions of the country.

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JESUDASON, M. V., V. BALAJI, U. MUKUNDAN et C. J. THOMSON. « Ecological study of Vibrio cholerae in Vellore ». Epidemiology and Infection 124, n^o 2 (avril 2000) : 201–6. http://dx.doi.org/10.1017/s095026889900357x.

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Vellore is endemic for cholera due to Vibrio cholerae O1 and O139. In a previous study the prevalence of Vibrio cholerae in drinking water, lakes and sewage outfalls in a single 2-months period in Vellore, India was determined. In addition water samples from three sites were also tested for the presence of V. cholerae O1 and O139 by fluorescent antibody staining. This follow on study has examined how the environmental distribution of V. cholerae at the same sites alters over a 12-month period and the relationship to the clinical pattern of cholera in Vellore. Samples of water were collected from fixed sites at three water bodies each month between April 1997 and March 1998. Bacteria isolated from samples were identified by standard biochemical tests and isolated strains of V. cholerae tested for their ability to agglutinate O1 and O139 antisera. Samples were also tested for the presence of V. cholerae O1 and O139 by fluorescent antibody staining. The clinical isolation rate of V. cholerae in Vellore, maximum temperature and rainfall were also studied. The results demonstrate the presence in the environment of viable but non-cultivable (VNC) V. cholerae in 10 of 12 months of the study year as well as their viability. Their prevalence in the environment also correlated with the isolation of these pathogens from clinical samples over the same study period.

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Islam, M. S., S. Mahmuda, M. G. Morshed, H. B. M. Bakht, M. N. H. Khan, R. B. Sack et D. A. Sack. « Role of cyanobacteria in the persistence of Vibrio cholerae O139 in saline microcosms ». Canadian Journal of Microbiology 50, n^o 2 (1 février 2004) : 127–31. http://dx.doi.org/10.1139/w03-114.

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Recently, a new strain of cholera, Vibrio cholerae O139, has emerged as an epidemic strain, but there is little information about its environmental reservoir. The present investigation was aimed to determine the role of cyanobacteria in the persistence of V. cholerae O139 in microcosms. An environmental isolate of V. cholerae O139 and three cyanobacteria (Anabaena sp., Nostoc sp., and Hapalosiphon sp.) were used in this study. Survival of culturable V. cholerae O139 in microcosms was monitored using taurocholate-tellurite gelatin agar medium. Viable but nonculturable V. cholerae O139 were detected using a fluorescent antibody technique. Vibrio cholerae O139 could be isolated for up to 12 days in a culturable form in association with cyanobacteria but could not be isolated in the culturable form after 2 days from control water without cyanobacteria. The viable but nonculturable V. cholerae O139 could be detected in association with cyanobacteria for up to 15 months. These results, therefore, suggest that cyanobacteria can act as a long-term reservoir of V. cholerae O139 in an aquatic environment.Key words: cyanobacteria, persistence, Vibrio cholerae, microcosm, reservoir.

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Boyd, E. Fidelma, Kathryn E. Moyer, Lei Shi et Matthew K. Waldor. « Infectious CTXΦ and the Vibrio Pathogenicity Island Prophage in Vibrio mimicus : Evidence for Recent Horizontal Transfer between V. mimicus and V. cholerae ». Infection and Immunity 68, n^o 3 (1 mars 2000) : 1507–13. http://dx.doi.org/10.1128/iai.68.3.1507-1513.2000.

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ABSTRACT Vibrio mimicus differs from Vibrio choleraein a number of genotypic and phenotypic traits but like V. cholerae can give rise to diarrheal disease. We examined clinical isolates of V. mimicus for the presence of CTXΦ, the lysogenic filamentous bacteriophage that carries the cholera toxin genes in epidemic V. cholerae strains. Four V. mimicus isolates were found to contain complete copies of CTXΦ. Southern blot analyses revealed that V. mimicus strain PT5 contains two CTX prophages integrated at different sites within theV. mimicus genome whereas V. mimicus strains PT48, 523-80, and 9583 each contain tandemly arranged copies of CTXΦ. We detected the replicative form of CTXΦ, pCTX, in all four of theseV. mimicus isolates. The CTX prophage in strain PT5 was found to produce infectious CTXΦ particles. The nucleotide sequences of CTXΦ genes orfU and zot from V. mimicus strain PT5 and V. cholerae strain N16961 were identical, indicating contemporary horizontal transfer of CTXΦ between these two species. The receptor for CTXΦ, the toxin-coregulated pilus, which is encoded by another lysogenic filamentous bacteriophage, VPIΦ, was also present in the CTXΦ-positive V. mimicus isolates. The nucleotide sequences of VPIΦ genes aldA and toxT fromV. mimicus strain PT5 and V. cholerae N16961 were identical, suggesting recent horizontal transfer of this phage between V. mimicus and V. cholerae. In V. mimicus, the vibrio pathogenicity island prophage was integrated in the same chromosomal attachment site as in V. cholerae. These results suggest that V. mimicus may be a significant reservoir for both CTXΦ and VPIΦ and may play an important role in the emergence of new toxigenic V. cholerae isolates.

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Panja, Prabir. « Optimal Control Analysis of a Cholera Epidemic Model ». Biophysical Reviews and Letters 14, n^o 01 (mars 2019) : 27–48. http://dx.doi.org/10.1142/s1793048019500024.

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In this paper, a cholera disease transmission mathematical model has been developed. According to the transmission mechanism of cholera disease, total human population has been classified into four subpopulations such as (i) Susceptible human, (ii) Exposed human, (iii) Infected human and (iv) Recovered human. Also, the total bacterial population has been classified into two subpopulations such as (i) Vibrio Cholerae that grows in the infected human intestine and (ii) Vibrio Cholerae in the environment. It is assumed that the cholera disease can be transmitted in a human population through the consumption of contaminated food and water by Vibrio Cholerae bacterium present in the environment. Also, it is assumed that Vibrio Cholerae bacterium is spread in the environment through the vomiting and feces of infected humans. Positivity and boundedness of solutions of our proposed system have been investigated. Equilibrium points and the basic reproduction number [Formula: see text] are evaluated. Local stability conditions of disease-free and endemic equilibrium points have been discussed. A sensitivity analysis has been carried out on the basic reproduction number [Formula: see text]. To eradicate cholera disease from the human population, an optimal control problem has been formulated and solved with the help of Pontryagin’s maximum principle. Here treatment, vaccination and awareness programs have been considered as control parameters to reduce the number of infected humans from cholera disease. Finally, the optimal control and the cost-effectiveness analysis of our proposed model have been performed numerically.

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Zadnova, S. P., N. A. Plekhanov, T. A. Kul’shan’, I. G. Shvidenko et A. A. Kritsky. « Vibrio cholerae secretion system of the type VI ». Problems of Particularly Dangerous Infections, n^o 2 (8 juillet 2022) : 27–35. http://dx.doi.org/10.21055/0370-1069-2022-2-27-35.

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The review summarizes literature data on the Vibrio cholerae secretion system of the 6th type. This system is a contact-dependent macromolecular mechanism through which bacteria translocate toxic effector proteins into target cells. It is found in many Gram-negative bacteria, including Vibrio cholerae. V. cholerae infects phagocytic amoebae, nematodes, ciliates, bacteria belonging to different species, as well as unrelated strains of V. cholerae using this system. DNA released after lysis of competing bacteria can be taken up by Vibrio cholerae cells, which leads to the acquisition of new genetic material. The type VI secretion system is involved in the infectious process. The destruction of macrophages and microbiota contributes to the active reproduction of the pathogen and colonization of host epitheliocytes, and the production of effector proteins causes the development of diarrhea and intestinal inflammation. Cholera vibrio secretion system of the 6th type has a structure similar to other gram-negative bacteria. The genes encoding the proteins of this system are located in one large region of the second chromosome and in several additional clusters. It has been shown that toxigenic strains of V. cholerae contain an identical set of secretion system genes, while their composition is variable in non-toxigenic isolates. The regulation of secretion system protein expression differs in V. cholerae strains of different toxigenicity, depends on a number of environmental signals, and is associated with other cell regulatory networks. The paper provides experimental data on the analysis of the structure of the global regulatory gene, vasH, of the type VI secretion system in toxigenic and non-toxigenic V. cholerae O1, biovar El Tor strains isolated in the Russian Federation. Thus, the type VI secretion system is an important mechanism that facilitates the survival of V. cholerae in complex communities in vitro, protects against damaging factors of the macroorganism and increases virulence in vivo, and also provides evolutionary transformations of cholera vibrio. Further study of this system will allow a better understanding of the pathogen-host interaction processes, as well as the adaptation mechanisms of V. cholerae in the external environment.

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Gromova, O. V., O. S. Durakova, S. V. Generalov, L. F. Livanova et O. A. Volokh. « Determination of Specific Activity of Cholera Chemical Vaccine Components using Cell Culture ». Biotekhnologiya 36, n^o 3 (2020) : 82–89. http://dx.doi.org/10.21519/0234-2758-2020-36-3-82-89.

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Том 36(2020) №3 стр. 82-89; DOI 10.21519/0234-2758-2020-36-3-82-89А.В. Гаева1*, О.В. Громова1, О.С. Дуракова1, С.В. Генералов1, Л.Ф. Ливанова1, О.А. Волох1 Определение специфической активности компонентов холерной химической вакцины с использованием культуры клеток 1ФКУЗ «Российский научно-исследовательский противочумный институт «Микроб»» Федеральной службы по надзору в сфере защиты прав потребителей и благополучия человека, Саратов 410005 *rusrapi@microbe.ru Поступила - 2019-11-26; После доработки - 2020-03-16; Принята к публикации - 2020-05-15 Список литературы Описаны методы определения динамики продукции токсинов штаммом Vibrio cholerae 569B при глубинном культивировании в биореакторе и антигенной активности специфической фракции холерогена-анатоксина по анатоксинсвязыванию с использованием клеточных культур. Показана высокая степень соответствия результатов, полученных методами, применяемыми для контроля этапов производства холерной химической вакцины и рассмотренными в данной работе. Отмечено, что применение клеточной линии СНО-К1 наиболее перспективно для замены биомоделей на промежуточных этапах контроля активных компонентов холерной химической вакцины. Разработанный методический подход впервые предлагается использовать на этапах производства холерной бивалентной химической вакцины. культура клеток, Vibrio cholerae, холерная химическая вакцина, контроль производства, холера. Vol 36(2020) N 3 p. 82-89; DOI 10.21519/0234-2758-2020-36-3-82-89A.V. Gaeva1*, O.V. Gromova1, O.S. Durakova1, S.V. Generalov1, L.F. Livanova1, O.A. Volokh1 Determination of Specific Activity of Cholera Chemical Vaccine Components using Cell Culture 1Russian Research Anti-Plague Institute «Microbe» of the Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing, Saratov, 410005 *rusrapi@microbe.ru Received - 26.11.2019; Accepted - 15.05.2020 References The methods has been described to determine the dynamics of toxin production by the Vibrio cholerae 569B strain during submerged cultivation in bioreactor and of the antigenic activity of specific choleragen anatoxin fraction by anatoxin binding levels using cell cultures. High degree of consistency was observed between the results obtained via the method under consideration and those obtained via control methods at different stages of cholera chemical vaccine production. It was shown that the CHO-K1 cell line is the most promising substitute for biomodels at the intermediate stages of control of active cholera chemical vaccine components. The developed methodological approach was first proposed for use at the stages of cholera chemical bivalent vaccine manufacturing. cell culture, Vibrio cholerae, cholera chemical vaccine, production control, cholera.

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Wyckoff, Elizabeth E., Benjamin E. Allred, Kenneth N. Raymond et Shelley M. Payne. « Catechol Siderophore Transport by Vibrio cholerae ». Journal of Bacteriology 197, n^o 17 (22 juin 2015) : 2840–49. http://dx.doi.org/10.1128/jb.00417-15.

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ABSTRACTSiderophores, small iron-binding molecules secreted by many microbial species, capture environmental iron for transport back into the cell.Vibrio choleraesynthesizes and uses the catechol siderophore vibriobactin and also uses siderophores secreted by other species, including enterobactin produced byEscherichia coli.E. colisecretes both canonical cyclic enterobactin and linear enterobactin derivatives likely derived from its cleavage by the enterobactin esterase Fes. We show here thatV. choleraedoes not use cyclic enterobactin but instead uses its linear derivatives.V. choleraelacked both a receptor for efficient transport of cyclic enterobactin and enterobactin esterase to promote removal of iron from the ferrisiderophore complex. To further characterize the transport of catechol siderophores, we show that the linear enterobactin derivatives were transported intoV. choleraeby either of the catechol siderophore receptors IrgA and VctA, which also transported the synthetic siderophore MECAM [1,3,5-N,N′,N″-tris-(2,3-dihydroxybenzoyl)-triaminomethylbenzene]. Vibriobactin is transported via the additional catechol siderophore receptor ViuA, while theVibrio fluvialissiderophore fluvibactin was transported by all three catechol receptors. ViuB, a putativeV. choleraesiderophore-interacting protein (SIP), functionally substituted for theE. coliferric reductase YqjH, which promotes the release of iron from the siderophore in the bacterial cytoplasm. InV. cholerae, ViuB was required for the use of vibriobactin but was not required for the use of MECAM, fluvibactin, ferrichrome, or the linear derivatives of enterobactin. This suggests the presence of another protein inV. choleraecapable of promoting the release of iron from these siderophores.IMPORTANCEVibrio choleraeis a major human pathogen and also serves as a model for theVibrionaceae, which include other serious human and fish pathogens. The ability of these species to persist and acquire essential nutrients, including iron, in the environment is epidemiologically important but not well understood. In this work, we characterize the ability ofV. choleraeto acquire iron by using siderophores produced by other organisms. We resolve confusion in the literature regarding its ability to use theEscherichia colisiderophore enterobactin and identify the receptor and TonB system used for the transport of several siderophores. The use of some siderophores did not require the ferric reductase ViuB, suggesting that an uncharacterized ferric reductase is present inV. cholerae.

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Agyei, Foster K., Birgit Scharf et Samuel Duodu. « Vibrio cholerae Bacteremia : An Enigma in Cholera-Endemic African Countries ». Tropical Medicine and Infectious Disease 9, n^o 5 (2 mai 2024) : 103. http://dx.doi.org/10.3390/tropicalmed9050103.

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Cholera is highly endemic in many sub-Saharan African countries. The bacterium Vibrio cholerae is responsible for this severe dehydrating diarrheal disease that accounts for over 100,000 deaths each year globally. In recent years, the pathogen has been found to invade intestinal layers and translocate into the bloodstream of humans. The non-toxigenic strains of V. cholerae (non-O1/O139), also known as NOVC, which do not cause epidemic or pandemic cases of cholera, are the major culprits of V. cholerae bacteremia. In non-cholera-endemic regions, clinical reports on NOVC infection have been noted over the past few decades, particularly in Europe and America. Although low–middle-income countries are most susceptible to cholera infections because of challenges with access to clean water and inappropriate sanitation issues, just a few cases of V. cholerae bloodstream infections have been reported. The lack of evidence-based research and surveillance of V. cholerae bacteremia in Africa may have significant clinical implications. This commentary summarizes the existing knowledge on the host risk factors, pathogenesis, and diagnostics of NOVC bacteremia.

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Ezeamagu, Christopher E., Mande Garuba et Toyosi F. Osisami. « Identification of Vibrio Cholerae using Analytical Profile Index (API 20E) ». International Journal of Research and Innovation in Applied Science IX, n^o V (2024) : 108–11. http://dx.doi.org/10.51584/ijrias.2024.905009.

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Cholera outbreak have resulted in the deaths of millions of people globally. The cholera-causing Vibrio cholerae, has multiple serogroups, and produces epidemics when two strains, O1 and O139, are present. With the exception of recent, rare instances, V. cholerae O139 caused prior outbreaks; however, V. cholerae O1 was responsible for all following epidemics. Hence, identification of the V. cholerae is an important step in the control of cholera outbreak especially in the local community where inadequate facilities for prognosis limit prompt treatment of patients. A total of 15 isolates previously identified with molecular method were subjected to TCBS Agar and Analytical Profile Index. All the sucrose-fermenting colonies on TCBS agar were correctly identified with API kit. The study concluded that API kit can be substituted for molecular method in prognosis of Cholera outbreak especially in resource-limited Countries due cost implication.

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Joelsson, Adam, Biao Kan et Jun Zhu. « Quorum Sensing Enhances the Stress Response in Vibrio cholerae ». Applied and Environmental Microbiology 73, n^o 11 (13 avril 2007) : 3742–46. http://dx.doi.org/10.1128/aem.02804-06.

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ABSTRACT Vibrio cholerae lives in aquatic environments and causes cholera. Here, we show that quorum sensing enhances V. cholerae viability under certain stress conditions by upregulating the expression of RpoS, and this regulation acts through HapR, suggesting that a quorum-sensing-enhanced stress response plays a role in V. cholerae environmental survival.

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Howell, Matthew, Daniel G. Dumitrescu, Lauren R. Blankenship, Darby Herkert et Stavroula K. Hatzios. « Functional characterization of a subtilisin-like serine protease from Vibrio cholerae ». Journal of Biological Chemistry 294, n^o 25 (10 mai 2019) : 9888–900. http://dx.doi.org/10.1074/jbc.ra119.007745.

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Vibrio cholerae, the causative agent of the human diarrheal disease cholera, exports numerous enzymes that facilitate its adaptation to both intestinal and aquatic niches. These secreted enzymes can mediate nutrient acquisition, biofilm assembly, and V. cholerae interactions with its host. We recently identified a V. cholerae-secreted serine protease, IvaP, that is active in V. cholerae-infected rabbits and human choleric stool. IvaP alters the activity of several host and pathogen enzymes in the gut and, along with other secreted V. cholerae proteases, decreases binding of intelectin, an intestinal carbohydrate-binding protein, to V. cholerae in vivo. IvaP bears homology to subtilisin-like enzymes, a large family of serine proteases primarily comprised of secreted endopeptidases. Following secretion, IvaP is cleaved at least three times to yield a truncated enzyme with serine hydrolase activity, yet little is known about the mechanism of extracellular maturation. Here, we show that IvaP maturation requires a series of sequential N- and C-terminal cleavage events congruent with the enzyme's mosaic protein domain structure. Using a catalytically inactive reporter protein, we determined that IvaP can be partially processed in trans, but intramolecular proteolysis is most likely required to generate the mature enzyme. Unlike many other subtilisin-like enzymes, the IvaP cleavage pattern is consistent with stepwise processing of the N-terminal propeptide, which could temporarily inhibit, and be cleaved by, the purified enzyme. Furthermore, IvaP was able to cleave purified intelectin, which inhibited intelectin binding to V. cholerae. These results suggest that IvaP plays a role in modulating intelectin–V. cholerae interactions.

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CLARK, C. G., A. N. KRAVETZ, C. DENDY, G. WANG, K. D. TYLER et W. M. JOHNSON. « Investigation of the 1994–5 Ukrainian Vibrio cholerae epidemic using molecular methods ». Epidemiology and Infection 121, n^o 1 (août 1998) : 15–29. http://dx.doi.org/10.1017/s0950268898008814.

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Thirty-seven Vibrio cholerae and four non-cholera Vibrio isolates from Ukraine, including strains from the epidemic of 1994–5, were analysed by molecular methods. Results from PFGE and ribotyping indicated that all Ukrainian toxigenic V. cholerae were closely related to each other and to an isolate from a patient from Pakistan. A non-toxigenic river water strain obtained during the height of the epidemic was more distantly related to these V. cholerae strains, while the Vibrio parahaemolyticus isolates and Vibrio alginolyticus isolate were not closely related to V. cholerae or each other. ERIC- and REP-PCR allowed the differentiation of strains identical by other methods. The results obtained confirm that the epidemic Ukrainian strains are most closely related to seventh pandemic strains from Asia and support a hypothesis that the Ukrainian epidemic of 1994–5 was caused by toxigenic environmental strains surviving since the time of the 1991 Ukrainian epidemic or before.

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