Cholerae Isolates Research Articles

Toxigenic Potential of Vibrio cholerae O1and O139 Serotypes Isolated from Cases of Diarrhea in Baghdad hospitals

Cholera is most important water borne pathogen. The public health significance of a V. cholerae isolate is routinely assessed by two critical properties: the production of cholera toxin CT and the possession of either the O1 or O139 antigen, which acts as a marker of epidemic potential. The objective of this study is to detect V. cholerae serotypes directly from stools and determines their toxiginicity potential. Sixty four stool samples were collected from four hospitals in Baghdad from November 2010 to February 2011. The age of patients was ranging from two months to 12 years, 26 females and 38 males. Immunochromatographic test used for qualitative detection of O1and /or O139 serotypes was used in addition to routine culture for isolation of V. cholerae. Using specific primer cholera toxin gene, ctxA2-B, was amplified and the PCR product was detected by agarose gel electrophoresis. Out of 64 stool samples only 16 (25%) was positive. Fifeen 93.7% of these samples were positive for O1serogroup and just one 6.3% was positive for O139 serogroup. Stool sample culture on alkaline peptone water and then on TCBS agar enhance the growth of 11(17.2%) V. cholerae isolates, 10 (90.9%) were belong to O1 serotype and one 9.1% belong to O139. The results of ctxA2-B gene amplification show that, 9 (90%) out of 10 O1serotypes was positive. While the only one 100% O139 serotype was positive. As conclusion, the incidence of cholera caused by V. cholerae O1 is more than that caused by V. cholerae O139 in Baghdad hospitals. Immunochromatographic test is a rapid and sensitive test in recover V. cholerae O1 and O139 serotypes. PCR is a simple molecular tool to determine the toxigenicity of V. cholerae isolates.

Vibrio ecology, pathogenesis, and evolution.

EDITORIAL article Front. Microbiol., 28 May 2014Sec. Aquatic Microbiology Volume 5 - 2014 | https://doi.org/10.3389/fmicb.2014.00256

Genetic elements associated with antimicrobial resistance among intestinal bacteria.

Background:Integrons are the major reasons of multidrug resistance (MDR) among enteropathogenic bacteria. Occurrence of horizontal gene transfer between integron-carrying microorganisms and other enteric bacteria may increase the rate of emergence of integron-associated antibiotic resistance.Objectives:The objective of this study was to investigate class 1 integrons among members of enteropathogenic bacteria isolated from patients in Iran.Materials and Methods:A total of 120 enteropathogenic bacterial isolates from diarrhoeal patients were included in this study. Identities of the isolates were investigated by biochemical tests and confirmed by genus or species specific PCRs. Antimicrobial susceptibility testing was performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Presence of class 1 integron among the isolates was investigated using primers specific for the integrase gene conserved region.Results:The result of this study showed the highest resistance to trimethoprim and cotrimoxazole, especially in enteropathogenic Escherichia coli (EPEC) (100%), Shigella sonnei (93.7%) and Vibrio cholerae (95%). The results showed that 16 (57.1%) of the 28 EPEC, 9 (25%) of the 36 Salmonella enterica, 32 of the 13 (40.6%) Sh. sonnei, and only 1 (4.2%) of the 24 V. cholerae isolate harbored class 1 integron.Conclusions:The data obtained in the present study suggested that class 1 integrons are widely distributed among members of Enterobacteriaceae. The resistance patterns of our E. coli, S. sonnei, and S. enterica isolates were nearly identical, suggesting the same genetic elements involved in attainment of multi-drug resistance.

Virulence factors in environmental and clinical Vibrio cholerae from endemic areas in Kenya.

BackgroundSince 1971, Kenya has had repeated cholera outbreaks. However, the cause of seasonal epidemics of cholera is not fully understood and neither are the factors that drive epidemics, both in Kenya and globally.ObjectivesThe objectives of the study were to determine the environmental reservoirs of V. cholerae during an interepidemic period in Kenya and to characterise their virulence factors.MethodsOne hundred (50 clinical, 50 environmental) samples were tested for V. cholerae isolates using both simplex and multiplex polymerase chain reaction.ResultsBoth sediments and algae from fishing and landing bays yielded isolates of V. cholerae. Clinical strains were characterised along with the environmental strains for comparison. All clinical strains harboured ctxA, tcpA (El Tor), ompU, zot, ace, toxR, hylA (El Tor) and tcpI genes. Prevalence for virulence genes in environmental strains was hylA (El Tor) (10%), toxR (24%), zot (22%), ctxA (12%), tcpI (8%), hylA (26%) and tcpA (12%).ConclusionThe study sites, including landing bays and beaches, contained environmental V. cholerae, suggesting that these may be reservoirs for frequent epidemics. Improved hygiene and fish-handling techniques will be important in reducing the persistence of reservoirs.

Genomic aspects of cholera and its relevance to cholera control

Toxigenic Vibrio cholerae belonging to serogroups O1 or O139 are water and food borne pathogens that cause the disease cholera. The fifth and sixth pandemics of cholera were caused by the classical biotype while the current seventh pandemic is caused by the El Tor biotype, which has now completely replaced the classical biotype. Molecular studies have further defined three new variants of El Tor V. cholerae O1 associated with cholera. The three variants are i) the Matlab variants which could not be biotyped by conventional methods since they had a combination of both classical and El Tor traits, ii) altered El Tor O1 strains which displayed typical traits of the El Tor biotype but carried the classical CTX prophage and iii) altered O1 El Tor isolates which harbored ctxB of classical origin. The altered El Tor variants produce higher quantities of cholera toxin as compared to the prototype El Tor and classical biotypes. The current pandemic caused by the El Tor biotype has shown subtle but distinct changes in the epidemiology and clinical presentation of the disease and also in the virulence and molecular traits. There has also been a change in the epidemiology of the disease with the burden of disease dominating in the under 5 year age group particularly in cholera endemic areas of south east Asia. Another unusual trend recently witnessed is the protracted nature of cholera outbreaks with high case fatality. Single nucleotide polymorphisms in 154 whole-genome sequences of globally and temporally representative V. cholerae isolates show that the seventh pandemic has spread from the Bay of Bengal in at least three independent but overlapping waves, and identified several transcontinental transmission events. From the studies on the genomes of V. cholerae, two facts have emerged. One is that variants of V. cholerae O1 emerge in cholera hyper endemic areas due to the intense transmission. The other fact is that all the three new waves of the El Tor variants originated from the Bay of Bengal area. Taken together, genomic studies point to the adoption of intense cholera control programs in the cholera endemic Bay of Bengal area as a strategy to eliminate cholera in these endemic areas and thereby abort the emergence and spread of cholera over the region and the globe.

Prevalence of Vibrio cholerae O1 El Tor variant in a cholera-endemic zone of Kenya

Since 2007, Kenya has experienced an increase in cholera outbreaks characterized by a high fatality rate. In this study, we characterized 81 Vibrio cholerae isolates from diarrhoeal stool samples in Nyanza, a cholera-endemic lake region of Kenya, for virulence properties, clonality and antibiotic susceptibility. Eighty of these isolates were V. cholerae O1 El Tor variants carrying the classical ctxB gene sequence, while one isolate was V. cholerae non-O1/O139. All of the El Tor variants were of clonal origin, as revealed by PFGE, and were susceptible to ampicillin, tetracycline, ciprofloxacin, fosfomycin, kanamycin and norfloxacin. However, the isolates showed resistance to sulfamethoxazole/trimethoprim and streptomycin, and intermediate resistance to nalidixic acid, chloramphenicol and imipenem. The non-O1/O139 isolate carried the cholix toxin II gene (chxA II) and was susceptible to all antimicrobials tested except ampicillin. We propose that an El Tor variant clone caused the Nyanza cholera outbreak of 2007-2008.

Changing Trends of Antibiotic Susceptibility Pattern among Vibrio cholerae O1 Serovars from Sporadic Cases in Coastal Karnataka, South India

Changing patterns of antibiotic sensitivity of V cholerae is a major concern as Multiple-Antibiotic-Resistant (MAR) V. cholerae isolates are being reported from various parts of the world. The study was conducted to analyze the prevalence and antibiotic resistance pattern of V cholerae 01. Samples were processed according to the standard guidelines. Sporadic outbreaks occurred in June 2004 and March 2010. Antibiotic resistance was seen in the strains isolated. A large number of cholera epidemics have been associated with MAR strains of V cholerae. This makes it imperative that all isolates be constantly subjected to susceptibi lity testing and resistance patterns to each antibiotic be monitored.

Facile and Rapid Detection of Vibrio cholerae by Multiplex PCR Based on ompU, ctxA, and toxR Genes

Background: Several epidemic and endemic cases have been reported involving Vibrio cholerae (V. cholerae) as a causative organism in serious diarrheal diseases with high mortality. Hence, quick identification of this microorganism is critical for health care communities. Objectives: This investigation suggests an accurate, sensitive and rapid test to detect toxigenic and pathogenic species of V. cholerae simultaneously. Materials and methods: The standard bacteriological tests were utilized to isolate V. cholerae from the clinical samples. A multiplex PCR assay was carried out with three separate primers designed for ctxA, toxR and ompU genes, which play basic roles in toxigenicity and pathogenicity. To investigate the specificity of the designed primers, the amplification statuses of Salmonella typhi (S. typhi), Shigella dysenteriae (S. dysenteriae) and Escherichia coli O157:H7, as common intestinal pathogens, were evaluated. In addition, different concentrations of V. cholerae genome were used for determining the test sensitivity. Results: From the total of collected stool samples, 72 V. cholerae isolates were found and separated from the patients. All of them carried toxR and ompU genes, but ctxA gene was detected in only 61 isolates. The specificity and sensitivity of this test was 100%. Conclusions: Obtained data demonstrated that the designed assay is an accurate, easy, rapid, and cost-effective tool for detecting V. cholerae that can serve as an alternate to current bacteriological tests.

Emergence of Vibrio cholerae O1 classical biotype in 2012 in Iran

Cholera outbreaks annually occur in many parts of Iran. The aim of this study was to investigate the biotype and genotype diversity of V. cholerae isolates from recent outbreak (2012) in Iran and to characterize the ctxB allelic sequence of isolates. The ctxB sequence of all isolates was analyzed and compared with the reference ctxB sequences for El Tor and classical biotypes in GenBank database. The PFGE genotype specification of isolates was determined and genetic relatedness among isolates and also with those previously reported from Iran was assessed. Ten out of eleven isolates were identified as El Tor biotype and one single isolate belonged to classical biotype. All isolates except three possessed tcpA, ctxA, ctxB and wbeT genes. All the ctxB(+) isolates in this study (classical and El Tor biotypes) possessed the ctxB sequence of classical biotype allele providing evidences of El Tor variants. Eight out of 11 isolates (73%) showed identical pulsotypes (P1). Each of the remaining three isolates showed distinct pulsotypes (P2-P4) with more than three band differences. Pulsotype P2 was corresponded to an isolate (9%) with classical biotype. The result demonstrated diversity in virulence gene content of strains with identical PFGE patterns and also provided evidences of the import of a V. cholerae strain with classical biotype from out of our country as no classical biotype strain has been previously (1998-2011) reported from Iran. Emergence of V. cholerae with Classical biotype after at least one decade in Iran is alarming due to fear of expansion of V. cholerae strains with high virulence potential and signifies the need to monitor and analyze all new cases in countries with cholera outbreaks or even sporadic cases as this could conceivably affect the neighbouring countries and may expose the world to the seventh pandemic with Classical biotype strains.

Laboratory-confirmed cholera and rotavirus among patients with acute diarrhea in four hospitals in Haiti, 2012-2013.

An outbreak of cholera began in Haiti in October of 2010. To understand the progression of epidemic cholera in Haiti, in April of 2012, we initiated laboratory-enhanced surveillance for diarrheal disease in four Haitian hospitals in three departments. At each site, we sampled up to 10 hospitalized patients each week with acute watery diarrhea. We tested 1,616 specimens collected from April 2, 2012 to March 28, 2013; 1,030 (63.7%) specimens yielded Vibrio cholerae, 13 (0.8%) specimens yielded Shigella, 6 (0.4%) specimens yielded Salmonella, and 63 (3.9%) specimens tested positive for rotavirus. Additionally, 13.5% of children < 5 years old tested positive for rotavirus. Of 1,030 V. cholerae isolates, 1,020 (99.0%) isolates were serotype Ogawa, 9 (0.9%) isolates were serotype Inaba, and 1 isolate was non-toxigenic V. cholerae O139. During 1 year of surveillance, toxigenic cholera continued to be the main cause of acute diarrhea in hospitalized patients, and rotavirus was an important cause of diarrhea-related hospitalizations in children.

Vibrio choleraeO1 El Tor and O139 Bengal Strains CarryingctxBET, Bangladesh

<i>Vibrio cholerae</i>O1 El Tor and O139 Bengal Strains Carrying<i>ctxB</i>^ET, Bangladesh

Prevalence and antimicrobial susceptibility of Vibrio species related to food safety isolated from shrimp cultured at inland ponds in Thailand

Inland farming of marine shrimp species is a relatively recent development, in response to increasing demand for the products. This study aimed to investigate the prevalence and antimicrobial resistance of potentially pathogenic Vibrio species in shrimps cultured at inland ponds with low salinity in Thailand. Of 16 shrimp samples (white-leg shrimps and black-tiger shrimps) from ponds with water temperatures from 29 to 32 °C, and salinities from 1 to 5 parts per trillion, 15 contained Vibrio cholerae (densities: 62–252,000 MPN/g). Vibrio parahaemolyticus was present in six samples (370–6,300,000 MPN/g), and Vibrio vulnificus was present in two samples (16–1300 MPN/g). V. parahaemolyticus has higher affinity for non-native white-leg shrimp than for native black-tiger shrimp. The minimum inhibitory concentrations were then measured for 12 common antimicrobial agents. Resistance to ampicillin and oxytetracycline (8% and 2% of the isolates) was documented in V. cholerae isolates, resistance to ampicillin and oxytetracycline (72% and 3%) was found in V. parahaemolyticus isolates, and resistance to nalidixic acid (20%) was detected in V. vulnificus isolates. β-lactamase and tetracycline resistance genes were detected in the resistant Vibrio isolates. The oxytetracycline-resistance phenotype was eliminated by plasmid curing, suggesting that the resistance was related to R-plasmids. Our results show that shrimps cultured even in low salinity ponds are potentially contaminated with pathogenic Vibrio species, and that shrimp are a vehicle for transfer of species with antimicrobial resistance genes to the public.

Molecular Characterization of the Circulating Strains of Vibrio cholerae during 2010 Cholera Outbreak in Nigeria

This study aimed at characterizing the phenotypic and toxigenic status of circulating strains of cholera during outbreaks in Nigeria, employing molecular typing techniques. Two hundred and one samples of rectal swabs, stool, vomitus, water (from the well, borehole, sachet, stream, and tap) and disinfectants (sodium hypochlorite) were collected from three states in the country. The samples were inoculated on thiosulphate-citrate bile salt-sucrose (TCBS), Cary-Blair transport medium and smeared on glass slides for direct examination. The Vibrio cholerae isolates were serotyped, biotyped, and characterized using PCR of the cytotoxin gene A (ctxA), wbeO1, and wbfO139 gene primer. Of the 201 samples screened, 96 were positive for V cholerae O1 (48%), with 69 (72%) positive for ctxA gene. The results from this study showed that the circulating strains of cholera in Nigeria were of Ogawa serotype, also observed in other outbreaks in Nigeria (1991, 1992, and 1996). However, the strains were of the Classical biotype and were mainly (72%) ctxA gene-positive. This current investigation has confirmed the production of cholera toxin by the circulating strains, and this could be harnessed for possible cholera vaccine production in Nigeria.

Detection and confirmation of toxigenic &lt;i&gt;Vibrio cholerae&lt;/i&gt; O1 in environmental and clinical samples by a direct cell multiplex PCR

Epidemic cholera caused by toxigenic Vibrio cholerae O1 is a major health problem in several developing countries. Traditional methods for identifying V. cholerae involve cultural, biochemical and immunological assays which are cumbersome and often take several days to complete. In the present study, a direct cell multiplex PCR was developed targeting the ompW, ctxB and rfbO1 genes for confirmation of V. cholerae , its toxigenicity and serogroup O1, respectively from clinical and environmental samples. The detection sensitivity of the multiplex PCR was 1.9 x 10 3 V. cholerae per PCR reaction. A total of 31 environmental samples and 45 clinical V. cholerae isolates from different outbreaks were examined by the PCR. The assay was simple and specific, as there was no requirement for DNA extraction and no amplification was observed with other homologous bacteria used. The assay can be very useful for rapid surveillance of toxigenic V. cholerae O1 in environmental water samples, as well as for confirmation of clinical isolates.

Population Structure and Evolution of Non-O1/Non-O139 Vibrio cholerae by Multilocus Sequence Typing

Pathogenic non-O1/non-O139 Vibrio cholerae strains can cause sporadic outbreaks of cholera worldwide. In this study, multilocus sequence typing (MLST) of seven housekeeping genes was applied to 55 non-O1/non-O139 isolates from clinical and environmental sources. Data from five published O1 isolates and 17 genomes were also included, giving a total of 77 isolates available for analysis. There were 66 sequence types (STs), with the majority being unique, and only three clonal complexes. The V. cholerae strains can be divided into four subpopulations with evidence of recombination among the subpopulations. Subpopulations I and III contained predominantly clinical strains. PCR screening for virulence factors including Vibrio pathogenicity island (VPI), cholera toxin prophage (CTXΦ), type III secretion system (T3SS), and enterotoxin genes (rtxA and sto/stn) showed that combinations of these factors were present in the clinical isolates with 85.7% having rtxA, 51.4% T3SS, 31.4% VPI, 31.4% sto/stn (NAG-ST) and 11.4% CTXΦ. These factors were also present in environmental isolates but at a lower frequency. Five strains previously mis-identified as V. cholerae serogroups O114 to O117 were also analysed and formed a separate population with V. mimicus. The MLST scheme developed in this study provides a framework to identify sporadic cholera isolates by genetic identity.

Horizontal gene transfer of a genetic island encoding a type III secretion system distributed in Vibrio cholerae

Twelve Vibrio cholerae isolates with genes for a type III secretion system (T3SS) were detected among 110 environmental and 14 clinical isolates. T3SS-related genes were distributed among the various serogroups and pulsed-field gel electrophoresis of NotI-digested genomes showed genetic diversity in these strains. However, the restriction fragment length polymorphism profiles of the T3SS-related genes had similar patterns. Additionally, naturally competent T3SS-negative V. cholerae incorporated the ca. 47 kb gene cluster of T3SS, which had been integrated into a site on the chromosome by recombination. Therefore, it is suggested that horizontal gene transfer of T3SS-related genes occurs among V. cholerae in natural ecosystems.

Ribotyping and TCP gene cluster analysis of environmental and clinical Vibrio cholerae strains isolated in Iran

The aim of this study was to investigate the presence of TCP gene clusters among clinical and environmental Vibrio cholerae isolates and to explore the genetic relatedness of isolates using ribotyping technique. A total of 50 V. cholerae strains (30 clinical and 20 environmental) were included in this study. Three clinical isolates were negative for TCP cluster genes while the cluster was absent in all of the environmental strains. Ribotyping of rRNA genes with BglI produced 18 different ribotype patterns, three of which belonged to clinical O1 serotype isolates. The remaining 15 ribotypes belonged to clinical non-O1, non-O139 serogroups (two patterns) and environmental non-O1, non-O139 serogroups (13 patterns). Clinical V. cholerae O1 strains from 2004 through 2006 and several environmental non-O1, non-O139 V. cholerae strains from 2006 showed 67.3 % similarity and fell within one single gene cluster. Ribotyping analysis made it possible to further comprehend the close originality of clinical isolates as very little changes have been occurred within rRNA genes of different genotypes of V. cholerae strains through years. In conclusion, ribotyping analysis of environmental V. cholerae isolates showed a substantial genomic diversity supporting the fact that genetic changes within bacterial genome occurs during years in the environment, while only little changes may arise within the genome of clinical isolates.

Large outbreak of cholera caused by El Tor variant Vibrio cholerae O1 in the eastern coast of Odisha, India during 2009.

A large outbreak of cholera reported during April-July 2009 in the Kendrapada district of Odisha, India was investigated. Forty-one rectal swabs and 41 water samples, collected from diarrhoeal patients and from different villages were bacteriologically analysed for the isolation of bacterial enteriopathogens, antibiogram profile and detection of various toxic genes. The bacteriological analysis of rectal swabs and environmental water samples revealed the presence of V. cholerae O1 Ogawa biotype El Tor. The V. cholerae strains were resistant to ciprofloxacin, co-trimoxazole, chloramphenicol, streptomycin, ampicillin, furazolidone and nalidixic acid. The multiplex polymerase chain reaction (PCR) assay on V. cholerae strains revealed the presence of ctxA and tcpA genes. The mismatch amplification of mutation assay (MAMA) PCR on clinical and environmental isolates of V. cholerae revealed that the strains were El Tor biotype, which harboured the ctxB gene of the classical strain. The random amplified polymorphic DNA PCR analysis and pulsed-field gel electrophoresis results indicated that the V. cholerae isolates belonged to the same clone. This investigation gives a warning that the El Tor variant of V. cholerae has spread to the coastal district causing a large outbreak that requires close monitoring and surveillance on diarrhoeal outbreaks in Odisha.

Molecular analysis of non-O1/non-O139 Vibrio choleraeisolated from hospitalised patients in China

BackgroundCholera is still a significant public health issue in developing countries. The aetiological agent is Vibrio cholerae and only two serogroups, O1 and O139, are known to cause pandemic or epidemic cholera. In contrast, non-O1/non-O139 V. cholerae has only been reported to cause sporadic cholera-like illness and localised outbreaks. The aim of this study was to determine the genetic diversity of non-O1/non-O139 V. cholerae isolates from hospitalised diarrhoeal patients in Zhejiang Province, China.ResultsIn an active surveillance of enteric pathogens in hospitalised diarrhoeal patients, nine non-O1/non-O139 V. cholerae isolates were identified from 746 diarrhoeal stool samples at a rate of 1.2%. These isolates and an additional 31 isolates from sporadic cases and three outbreaks were analysed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). PFGE divided the isolates into 25 PFGE types while MLST divided them into 15 sequence types (STs). A single ST, ST80, was predominant which persisted over several years in different cities and caused two outbreaks in recent years. Antibiotic resistance varied with the majority of the isolates resistant to sulphamethoxazole/trimethoprim and nearly all isolates either resistant or intermediate to erythromycin and rifampicin. None of the isolates carried the cholera toxin genes or toxin co-regulated pilus genes but the majority carried a type III secretion system as the key virulence factor.ConclusionsNon-O1/non-O139 V. cholerae is an important contributor to diarrhoeal infections in China. Resistance to commonly used antibiotics limits treatment options. Continuous surveillance of non-O1/non-O139 V. cholerae is important for control and prevention of diarrhoeal infections.

Cholera Outbreaks in Nigeria Are Associated with Multidrug Resistant Atypical El Tor and Non-O1/Non-O139 Vibrio cholerae

BackgroundThe current millennium has seen a steep rise in the number, size and case-fatalities of cholera outbreaks in many African countries. Over 40,000 cases of cholera were reported from Nigeria in 2010. Variants of Vibrio cholerae O1 El Tor biotype have emerged but very little is known about strains causing cholera outbreaks in West Africa, which is crucial for the implementation of interventions to control epidemic cholera.Methodology/Principal Findings V. cholerae isolates from outbreaks of acute watery diarrhea in Nigeria from December, 2009 to October, 2010 were identified by standard culture methods. Fifteen O1 and five non-O1/non-O139 strains were analyzed; PCR and sequencing targeted regions associated with virulence, resistance and biotype were performed. We also studied genetic interrelatedness among the strains by multilocus sequence analysis and pulsed-field gel electrophoresis. The antibiotic susceptibility was tested by the disk diffusion method and E-test. We found that multidrug resistant atypical El Tor strains, with reduced susceptibility to ciprofloxacin and chloramphenicol, characterized by the presence of the SXT element, and gyrA Ser83Ile/parC Ser85Leu alleles as well CTX phage and TCP cluster characterized by rstR ElTor, ctxB-7 and tcpA CIRS alleles, respectively, were largely responsible for cholera outbreaks in 2009 and 2010. We also identified and characterized a V. cholerae non-O1/non-O139 lineage from cholera-like diarrhea cases in Nigeria.Conclusions/SignificanceThe recent Nigeria outbreaks have been determined by multidrug resistant atypical El Tor and non-O1/non-O139 V. cholerae strains, and it seems that the typical El Tor, from the beginning of seventh cholera pandemic, is no longer epidemic/endemic in this country. This scenario is similar to the East Africa, Asia and Caribbean countries. The detection of a highly virulent, antimicrobial resistant lineage in Nigeria is worrisome and points to a need for vaccine-based control of the disease. This study has also revealed the putative importance of non-O1/non-O139 V. cholerae in diarrheal disease in Nigeria.