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Note: Characterization of Vibrio cholerae O139 Bengal isolated from water in Malaysia

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Abstract

R. SON, G. RUSUL, L. SAMUEL, YUHERMAN, S. SENTHIL, A. RASIP, E.H. NASRELDIN AND M. NISHIBUCHI. 1998. Four Vibrio cholerae O139 Bengal strains isolated from surface water were characterized by antibiotic resistance, plasmid profile, presence of cholera toxin gene and random amplification of polymorphic DNA (RAPD) analysis. All four strains exhibit multiple resistance towards the antibiotics tested with a multiple antibiotic resistance index of 0·5–0·66, and harboured a 2·0 MDa non-conjugative plasmid. The Vibrio cholerae O139 Bengal were positive for the cholera toxin gene. Antibiotyping and random amplification of polymorphic DNA analysis with four primers proved to be useful in discriminating the isolates. RAPD proved to be more sensitive. These results reveal that there is significant genetic diversity among the Vibrio cholerae O139 Bengal strains studied.

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... An El Tor O1 Inaba strain isolated from a patient during an outbreak in Sarawak, Malaysia, in 1998 was provided by Patrick Benjamin Guda Miri of the General Hospital, Miri, Sarawak. Toxigenic O139 strains isolated from seawater in Malaysia in 1996 were described previously (38). Other V. cholerae O1 Ogawa strains isolated from international travelers arriving in Japan from various Asian countries between 1982 and 1998 were supplied by Osaka Airport Quarantine Station, Kansai Airport Quarantine Station, and Nagoya Airport Quarantine Station, Japan. ...
... The 20 toxigenic strains were isolated from various kinds of seafoods collected at various locations in Malaysia (Table 1). This result and the isolation of toxigenic O139 strains from seawater in Malaysia in 1996 (38) suggest that the aquatic environment may serve as the reservoir for toxigenic V. cholerae in Malaysia. ...
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Of 97 strains of Vibrio cholerae isolated from various seafoods in Malaysia in 1998 and 1999, 20 strains carried the ctx gene and produced cholera toxin. Fourteen, one, and five of these toxigenic strains belonged to the O139, O1 Ogawa, and rough serotypes, respectively. The rough strains had the rfb gene of the O1 serotype. The toxigenic strains varied in their biochemical characteristics, the amount of cholera toxin produced, their antibiograms, and the presence or absence of the pTLC plasmid sequence. DNA fingerprinting analysis by arbitrarily primed PCR, ribotyping, and a pulsed-field gel electrophoresis method classified the toxigenic strains into 3, 7, and 10 types, respectively. The relatedness of these toxigenic strains to clinical strains isolated in other countries and from international travelers was examined by using a dendrogram constructed from the pulsed-field gel electrophoresis profiles. The results of the examination of the antibiogram and the possession of the toxin-linked cryptic plasmid were consistent with the dendrogram-based relatedness: the O139 strains isolated from Malaysian seafoods could be separated into two groups that appear to have been introduced from the Bengal area independently. The rough strains of Malaysian seafood origin formed one group and belonged to a cluster unique to the Thailand-Malaysia-Laos region, and this group may have persisted in this area for a long period. The single O1 Ogawa strain detected in Malaysian seafood appears to have an origin and route of introduction different from those of the O139 and the rough strains.
... Bacteria with highest frequency of resistance towards commonly use antibiotics have been isolated from hospitals and its environments such as hospital effluents, other sources like sewage and waste water (Chandrasekaran et al., 1998;Moges et al., 2014). The presence of multiple antibiotic resistant bacteria in various water environments have been reported in Malaysia (Son et al., 1998;Samuel et al., 2011;Abdullahi et al., 2013;Ng et al., 2014;Lesley et al., 2016). It has also been reported that the multiple resistant bacteria are also presence in recreational water which constitute a direct threat to those associated with the water through potential transfer of resistance to human and animal strains (Pathaka et al., 1993;Alonso et al., 2001;Yin et al., 2013;Zhu et al., 2013). ...
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Enterobacteriaceae is a large family within the Gram-negative bacteria that primarily inhabits in the gastrointestinal tract of human and animals. The bacteria within this group are readily survived in the environment with some species found living free in the water where energy sources are scarce, making them ideal indicators for faecal contamination of the river water. Some species within the family have been used as indicator for the presence of pathogenic bacteria whilst on the other hand some species have been directly associated with various diseases in human and animals. The main aim of this research study was to determine the distribution and characteristics of the Enterobacteriaceae in water samples collected from river and waterfalls within a community resort. The health risk associated with the bacteria was analysed with regard to their susceptibility to antibiotics. Samples were collected from surface water and water falling down directly from waterfalls of river within the community resort. The samples collected were plated onto Eosine Methylene Blue agar (EMBA) for the isolation of the Enterobacteriaceae. Bacterial colonies growing on the agar were randomly picked, purified, stocked and then identified using API 20E identification kit. DNA fingerprinting using (GTG)5-PCR was utilised to determine their genetic profiles before the isolates were grouped into a dendrogram using RAPDistance software package. The level of antibiotic susceptibility of the bacteria isolates was analysed using disc diffusion technique. This study confirmed the presence of Enterobacter, Klebsiella, Citrobacter, Pantoea and Serratia in the water samples with their single and multiple antibiotic resistance and susceptible characteristics. The dendrogram presented in this study shows genetic similarities and differences among the strains, suggesting while there is a potential for single distribution of a clone, there is also possibility of the distribution of different strains within species in the water environment. Therefore, awareness on the potential risk associated with genetically diverse intermediate and resistant enteric bacteria in the recreational water should be communicated to the public especially communities within the study area.
... Bacteria with highest frequency of resistance towards commonly use antibiotics have been isolated from hospitals and its environments such as hospital effluents, other sources like sewage and waste water (Chandrasekaran et al., 1998;Moges et al., 2014). The presence of multiple antibiotic resistant bacteria in various water environments have been reported in Malaysia (Son et al., 1998;Samuel et al., 2011;Abdullahi et al., 2013;Ng et al., 2014;Lesley et al., 2016). It has also been reported that the multiple resistant bacteria are also presence in recreational water which constitute a direct threat to those associated with the water through potential transfer of resistance to human and animal strains (Pathaka et al., 1993;Alonso et al., 2001;Yin et al., 2013;Zhu et al., 2013). ...
Article
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Enterobacteriaceae is a large family within the Gram-negative bacteria that primarily inhabits in the gastrointestinal tract of human and animals. The bacteria within this group are readily survived in the environment with some species found living free in the water where energy sources are scarce, making them ideal indicators for faecal contamination of the river water. Some species within the family have been used as indicator for the presence of pathogenic bacteria whilst on the other hand some species have been directly associated with various diseases in human and animals. The main aim of this research study was to determine the distribution and characteristics of the Enterobacteriaceae in water samples collected from river and waterfalls within a community resort. The health risk associated with the bacteria was analysed with regard to their susceptibility to antibiotics. Samples were collected from surface water and water falling down directly from waterfalls of river within the community resort. The samples collected were plated onto Eosine Methylene Blue agar (EMBA) for the isolation of the Enterobacteriaceae. Bacterial colonies growing on the agar were randomly picked, purified, stocked and then identified using API 20E identification kit. DNA fingerprinting using (GTG)5-PCR was utilised to determine their genetic profiles before the isolates were grouped into a dendrogram using RAPDistance software package. The level of antibiotic susceptibility of the bacteria isolates was analysed using disc diffusion technique. This study confirmed the presence of Enterobacter, Klebsiella, Citrobacter, Pantoea and Serratia in the water samples with their single and multiple antibiotic resistance and susceptible characteristics. The dendrogram presented in this study shows genetic similarities and differences among the strains, suggesting while there is a potential for single distribution of a clone, there is also possibility of the distribution of different strains within species in the water environment. Therefore, awareness on the potential risk associated with genetically diverse intermediate and resistant enteric bacteria in the recreational water should be communicated to the public especially communities within the study area.
... The results of the ERIC-PCR fingerprint profiles supported the results obtained by ribotyping that multiple clones of V. cholerae O139 were present in the aquatic environment. These observations are in agreement with those of others who demonstrated heterogeneity in O139 V. cholerae strains (10, 17, 20, 29). cholerae O139 strains were positive for the ctxA, zot, ace, tcpA, ompU, and toxR genes (Table 2). ...
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Since October 1992, > 150,000 cases of cholera have been reported from India and Bangladesh; the great majority of Vibrio cholerae isolates belong to the newly established serogroup O139. To better understand the interaction of genetic and epidemiologic factors responsible for their sudden appearance and rapid spread, representative toxigenic V. cholerae O139 isolates were molecularly characterized and compared with a set of toxigenic V. cholerae O1 and non-O1/non-O139 strains. DNA sequences of the cholera toxin B subunit gene and multilocus enzyme electrophoresis markers of V. cholerae O139 strains were identical to those of V. cholerae O1 isolates of the seventh pandemic. Two distinct ribotypes and four pulsed-field gel electrophoretic patterns were observed for O139 strains. V. cholerae O139 strains were very similar to V. cholerae O1 strains of the seventh pandemic but clearly different from the toxigenic V. cholerae strains of serogroups other than O1 and O139.
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Large out-break of clinical cholera due to Vzbrio cholerue non-01 in Bang-ladesh. Luncet 341, 704. Anon. (1993) Performance standards for antimicrobial disc sus-ceptibility tests: tentative standards
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