RESUMEN

Cholera is a severe diarrhoeal disease that spreads rapidly and affects millions of people each year, resulting in tens of thousands of deaths. The disease is caused by Vibrio cholerae O1 and is characterized by watery diarrhoea that can be lethal if not properly treated. Cholera had not been reported in South America from the late 1800s until 1991, when it was introduced in Peru, wreaking havoc in one of the biggest epidemics reported to date. Within a year, the disease had spread to most of the Latin American region, resulting in millions of cases and thousands of deaths in all affected countries. Despite its aggressive entry, cholera virtually disappeared from the continent after 1999. The progression of the entire epidemic was well documented, making it an ideal model to understand cholera dynamics. In this review, we highlight how the synergy of socioeconomic, political and ecological factors led to the emergence, rapid spread and eventual disappearance of cholera in Latin America. We discuss how measures implemented during the cholera epidemic drastically changed its course and continental dynamics. Finally, we synthesize our findings and highlight potential lessons that can be learned for efficient and standardized cholera management programmes during future outbreaks in non-endemic areas.

Asunto(s)

Cólera/epidemiología , Control de Enfermedades Transmisibles/métodos , Vibrio cholerae O1/aislamiento & purificación , Cólera/patología , Cambio Climático , Epidemias , Humanos , América Latina/epidemiología , Política , Factores Socioeconómicos , América del Sur/epidemiología , Vibrio cholerae O1/inmunología

RESUMEN

Cholera posed a significant threat causing outbreaks/epidemics with high morbidity and mortality in Odisha. This study envisages the characterisation of isolated pathogen from two cholera outbreaks reported in 2018 and 2019 from Bargarh and Rayagada districts of Odisha respectively. Vibrio cholerae O1 were isolated following standard techniques. The different virulent and drug resistant genes were detected by multiplex PCR assays; whereas the ctxB genotypes were characterised through double mismatch amplification mutation (DMAMA) PCR assay. The ctxB genes were further sequenced and pulse-field gel electrophoresis (PFGE) was done on some selected strains. The clinical and water isolates of Haitian variant (HCT) V. cholerae O1 Ogawa biotype El Tor with multi drug resistant strains were isolated from both the places. All the V. cholerae O1 strains were positive for virulence genes. The antibiotic resistant genes like dfrA1 (100%), strB (76.9%), intSXT (61.5%) were detected. The PFGE results on V. cholerae O1 strains exhibited two different pulsotypes. These cholera outbreaks were due to multidrug resistant HCT variant V. cholerae O1 strains which were circulating and caused the cholera outbreaks in Odisha. So continuous surveillance on diarrheal disorders is highly essential to prevent the future diarrheal outbreaks in this region.

Asunto(s)

Cólera/epidemiología , Brotes de Enfermedades , Vibrio cholerae O1/genética , Vibrio cholerae O1/aislamiento & purificación , Adolescente , Adulto , Antibacterianos/uso terapéutico , Cólera/tratamiento farmacológico , Toxina del Cólera/genética , Diarrea/epidemiología , Diarrea/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Femenino , Genotipo , Haití , Humanos , India/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex/métodos , Reacción en Cadena de la Polimerasa , Virulencia/genética , Microbiología del Agua , Adulto Joven

RESUMEN

Introduction. The emergence of novel strains of Vibrio cholerae O1 El Tor biotype has gained attention due to causing several epidemics around the world. Variant strains have evolved as a result of the acquisition of genes that confer extended virulence and pathogenicity.Aim. This study aimed to determine the presence of the most recently emerging Haitian-like genetic traits among the isolates from Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry, Southern India. We also wanted to detect the prevalence of the sulfamethoxazole and trimethoprim (SXT) element, which is an integrating conjugative element (ICE) and the antimicrobial resistance genes present in our isolates.Methodology. Identification of Haitian-specific alleles was done by mismatched amplification mutation assay PCR (MAMA-PCR). The presence of SXT elements was carried out by PCR by detecting int, eex, att-prfC and setR genes. Detection of antibiotic resistance determinant, sul(1,2,3); dfr(A1,18,5) for trimethoprim resistance, tet(A,B,C,D,E,Y,G,M), tet34 for tetracycline resistance and erm(A,B,C), mph(A,B), ere(A,B), msr(A,D) for azithromycin resistance were targeted by PCR. The MIC of tetracycline, ciprofloxacin and azithromycin was determined by the E-test method.Results. Of the 95 isolates, 60 % of the isolates were found to carry Haitian-specific alleles of ctxB, tcpA and rtxA gene, 100 % of the isolates were found to carry SXT elements. All the isolates harboured the four conserved genes of the SXT element, except one which had only eex, att-prfC, setR genes. About 99 % harboured sul2 and dfrA1 genes. No tet and macrolide genes were detected. We observed a progressive increase in the MIC of azithromycin ranging from 0.75 µg ml-1 to 2 µg ml-1.Conclusion. None of the isolates were the prototype El Tor biotype. All the isolates were a Haitian variant. The presence of SXT elements across all our isolates and their creeping MIC of azithromycin is a matter of concern. Further testing for other genetic determinants of resistance will be carried out in our future studies.

Asunto(s)

Antibacterianos/farmacología , Azitromicina/farmacología , Cólera/epidemiología , Farmacorresistencia Bacteriana/genética , Vibrio cholerae O1/genética , Alelos , Cólera/microbiología , Ciprofloxacina/farmacología , Heces/microbiología , Transferencia de Gen Horizontal , Genotipo , Haití , Humanos , India/epidemiología , Pruebas de Sensibilidad Microbiana , Mutación , Fenotipo , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Tetraciclina/farmacología , Vibrio cholerae O1/aislamiento & purificación

RESUMEN

Cholera has affected Haiti with damping waves of outbreaks since October 2010. However, mechanisms behind disease persistence during lull periods remain poorly understood. By mid 2014, cholera transmission seemed to only persist in the northern part of Haiti. Meanwhile, cholera appeared nearly extinct in the capital, Port-au-Prince, where it eventually exploded in September 2014. This study aimed to determine whether this outbreak was caused by local undetected cases or by re-importation of the disease from the north. Applying an integrated approach between November 2013 and November 2014, we assessed the temporal and spatial dynamics of cholera using routine surveillance data and performed population genetics analyses of 178 Vibrio cholerae O1 clinical isolates. The results suggest that the northern part of the country exhibited a persisting metapopulation pattern with roaming oligoclonal outbreaks that could not be effectively controlled. Conversely, undetected and unaddressed autochthonous low-grade transmission persisted in the Port-au-Prince area, which may have been the source of the acute outbreak in late-2014. Cholera genotyping is a simple but powerful tool to adapt control strategies based on epidemic specificities. In Haiti, these data have already yielded significant progress in cholera surveillance, which is a key component of the strategy to eventually eliminate cholera.

Asunto(s)

Cólera/epidemiología , Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa , Genotipo , Recurrencia , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/genética , Cólera/microbiología , Cólera/transmisión , Haití/epidemiología , Humanos , Epidemiología Molecular , Tipificación Molecular , Análisis Espacio-Temporal , Vibrio cholerae O1/aislamiento & purificación

RESUMEN

PURPOSE: Two natural epidemic biotypes of Vibrio cholerae O1, classical and El Tor, exhibit different patterns of sensitivity against the antimicrobial peptide polymyxin B. This difference in sensitivity has been one of the major markers in biotype classification system for several decades. A recent report regarding the emergence of polymyxin B-sensitive El Tor V. cholerae O1 in Kolkata has motivated us to track the spread of the strains containing this important trait, along with Haitian-like genetic content, in different parts of India. METHODOLOGY: We have collected 260 clinical V. cholerae O1 strains from 12 states in India and screened them for polymyxin B susceptibility. Genetic characterization was also performed to study the tcpA, ctxB and rtxA genotypes by allele-specific polymerase chain reaction (PCR) and nucleotide sequencing. RESULTS: Interestingly, 88.85 % of the isolates were found to be sensitive to polymyxin B. All of the states, with the exception of Assam, had polymyxin B-sensitive V. cholerae strains and complete replacement with this strain was found in eight of the states. However, from 2016 onwards, all the strains tested showed sensitivity to polymyxin B. Allele-specific PCR and sequencing confirmed that all strains possessed Haitian-like genetic traits. CONCLUSION: Polymyxin B-sensitive strains have begun to spread throughout India and may lead to the revision of the biotype classification. The dissemination of these new variant strains needs to be carefully monitored in different endemic populations through active holistic surveillance to understand their clinical and epidemiological consequences.

Asunto(s)

Antibacterianos/farmacología , Cólera/microbiología , Polimixina B/farmacología , Vibrio cholerae O1/efectos de los fármacos , Vibrio cholerae O1/genética , Cólera/epidemiología , Farmacorresistencia Bacteriana , Genotipo , Humanos , India/epidemiología , Fenotipo , Vibrio cholerae O1/aislamiento & purificación

Asunto(s)

Cólera/epidemiología , Cólera/genética , Proteínas Fimbrias/aislamiento & purificación , Vibrio cholerae O1/aislamiento & purificación , Cólera/microbiología , Cólera/transmisión , Proteínas Fimbrias/genética , Haití/epidemiología , Humanos , India/epidemiología , Vibrio cholerae O1/genética , Vibrio cholerae O1/patogenicidad

RESUMEN

Vibrio cholerae is ubiquitous in aquatic environments, with environmental toxigenic V. cholerae O1 strains serving as a source for recurrent cholera epidemics and pandemic disease. However, a number of questions remain about long-term survival and evolution of V. cholerae strains within these aquatic environmental reservoirs. Through monitoring of the Haitian aquatic environment following the 2010 cholera epidemic, we isolated two novel non-toxigenic (ctxA/B-negative) Vibrio cholerae O1. These two isolates underwent whole-genome sequencing and were investigated through comparative genomics and Bayesian coalescent analysis. These isolates cluster in the evolutionary tree with strains responsible for clinical cholera, possessing genomic components of 6th and 7th pandemic lineages, and diverge from "modern" cholera strains around 1548 C.E. [95% HPD: 1532-1555]. Vibrio Pathogenicity Island (VPI)-1 was present; however, SXT/R391-family ICE and VPI-2 were absent. Rugose phenotype conversion and vibriophage resistance evidenced adaption for persistence in aquatic environments. The identification of V. cholerae O1 strains in the Haitian environment, which predate the first reported cholera pandemic in 1817, broadens our understanding of the history of pandemics. It also raises the possibility that these and similar environmental strains could acquire virulence genes from the 2010 Haitian epidemic clone, including the cholera toxin producing CTXϕ.

Asunto(s)

Cólera/microbiología , Vibrio cholerae O1/genética , Teorema de Bayes , Cólera/epidemiología , Cólera/patología , Toxina del Cólera/genética , Toxina del Cólera/metabolismo , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Haití/epidemiología , Humanos , Pandemias , Filogenia , Análisis de Secuencia de ADN , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/aislamiento & purificación , Microbiología del Agua , Secuenciación Completa del Genoma

RESUMEN

In October of 2010, an outbreak of cholera was confirmed in Haiti for the first time in more than a century. A single clone of toxigenic Vibrio cholerae O1 biotype El Tor serotype Ogawa strain was implicated as the cause. Five years after the onset of cholera, in October, 2015, we have discovered a major switch (ranging from 7 to 100%) from Ogawa serotype to Inaba serotype. Furthermore, using wbeT gene sequencing and comparative sequence analysis, we now demonstrate that, among 2013 and 2015 Inaba isolates, the wbeT gene, responsible for switching Ogawa to Inaba serotype, sustained a unique nucleotide mutation not found in isolates obtained from Haiti in 2012. Moreover, we show that, environmental Inaba isolates collected in 2015 have the identical mutations found in the 2015 clinical isolates. Our data indicate that toxigenic V. cholerae O1 serotype Ogawa can rapidly change its serotype to Inaba, and has the potential to cause disease in individuals who have acquired immunity against Ogawa serotype. Our findings highlight the importance of monitoring of toxigenic V. cholerae O1 and cholera in countries with established endemic disease.

Asunto(s)

Cólera/microbiología , Vibrio cholerae O1/aislamiento & purificación , Vibrio cholerae/aislamiento & purificación , Cólera/diagnóstico , Cólera/epidemiología , Microbiología Ambiental , Haití/epidemiología , Humanos , Serotipificación , Vibrio cholerae/clasificación , Vibrio cholerae/genética , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/genética

RESUMEN

BACKGROUND AND OBJECTIVES: The antimicrobial susceptibility patterns and genetic characteristics of Vibrio cholerae O1, which is responsible for several cholera epidemics in Nigeria, are not reported in detail since 2007. In this study, we screened V. cholerae O1 El Tor biotype isolates from cholera cases and water samples from different states to investigate their phenotypic and genetic attributes with special reference to their clonality. RESULTS: All the V. cholerae O1 biotype El Tor isolates isolated during 2007-2013 were susceptible to fluoroquinolones and tetracycline, the drugs currently used in the treatment of cholera cases in Nigeria. Emergence of CT genotype 7 (Haitian type of ctxB allele) was predominantly seen among Ogawa serotype and the CT genotype 1 (classical ctxB allele) was mostly found in Inaba serotype. Overall, V. cholerae O1 from clinical and water samples were found to be closely related as determined by the pulsed-field gel electrophoresis. V. cholerae isolates from Abia, Kano and Bauchi were found to be genetically distinct from the other states of Nigeria. CONCLUSION: Fecal contamination of the water sources may be the possible source of the cholera infection. Combined prevalence of Haitian and classical ctxB alleles were detected in Ogawa and Inaba serotypes, respectively. This study further demonstrated that V. cholerae O1 with the ctxB has been emerged similar to the isolates reported in Haiti. Our findings suggest that the use of fluoroquinolones or tetracycline/doxycycline may help in the effective management of acute cholera in the affected Nigerian states. In addition, strengthening the existing surveillance in the hospitals of all the states and supply of clean drinking water may control cholera outbreaks in the future.

Asunto(s)

Toxina del Cólera/genética , Cólera/diagnóstico , Vibrio cholerae O1/genética , Alelos , Antibacterianos/farmacología , Cólera/epidemiología , Cólera/microbiología , Toxina del Cólera/química , Toxina del Cólera/metabolismo , Estudios Transversales , Electroforesis en Gel de Campo Pulsado , Fluoroquinolonas/farmacología , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Nigeria/epidemiología , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Serogrupo , Tetraciclina/farmacología , Vibrio cholerae O1/efectos de los fármacos , Vibrio cholerae O1/aislamiento & purificación , Virulencia/genética

RESUMEN

UNLABELLED: Paranaguá Bay is one of the largest estuarine systems on the Southern Brazilian coast. The only recorded cholera outbreak in this region since the early 20th century occurred in 1999 and resulted in 467 cases and at least three reported deaths in a population of approx. 150 000 people. This short communication reports historical, unpublished data related to that outbreak. Water, zooplankton and bivalve samples were collected and evaluated using direct fluorescence assay to determine whether Vibrio cholerae serogroups O1 and O139 were present in the estuarine system at that time. Most of the water (83%) and zooplankton samples (75%) were positive for V. cholerae O1, while V. cholerae O139 was not detected. Shellfish (Mytella sp.) were also positive for V. cholerae O1. These results indicate that the estuary, including biological vectors such as copepods and bivalves, comprise an important reservoir of V. cholerae O1 and a probable waterborne pathway for the disease, in addition to contamination with untreated sewage. SIGNIFICANCE AND IMPACT OF THE STUDY: Despite most of the cholera cases that occurred in Brazil during the 7th pandemic were located in the northern areas of the country, a significant outbreak in Paranaguá, an estuary in the south coast, resulted in at least three deaths in 1999. We report here the detection of Vibrio cholerae O1 in water, zooplankton and bivalve samples during the outbreak, using direct fluorescence assay as an alternative method for the traditional plate culture employed at the time by the Brazilian Sanitary Agency. Results demonstrate that aquatic natural reservoirs comprise a potential route of transmission of cholera, in addition to untreated sewage and routine monitoring is recommended.

Asunto(s)

Bivalvos/microbiología , Cólera/epidemiología , Copépodos/microbiología , Aguas del Alcantarillado/microbiología , Vibrio cholerae O1/aislamiento & purificación , Zooplancton/microbiología , Animales , Brasil , Cólera/microbiología , Estuarios , Humanos , Pandemias , Microbiología del Agua

RESUMEN

Vibrio cholerae O1 biotype El Tor, the causative agent of the seventh pandemic, has recently been replaced by strains carrying classical and Haitian ctxB in India, Haiti and other parts of the world. We conducted phenotypic and genetic tests to characterize V. cholerae O1 isolated between 2012 and 2014 from Silvassa, India, to examine the presence of virulence and regulatory genes, seventh pandemic marker, ctxB type and biofilm formation and to study genomic diversity. Of the 59 V. cholerae O1, eight isolates belong to El Tor prototype, one to classical prototype and the remaining isolates have attributes of both classical and El Tor biotypes. PCR and ctxB gene sequencing revealed the presence of classical ctxB in four strains and Haitian ctxB in 55 isolates; indicating that isolates were either an El Tor or hybrid variant. All isolates carried virulence, regulatory, adherence, Vibrio seventh pandemic pathogenicity island I and seventh pandemic group-specific marker VC2346, in addition to tcpAET and rstRET, the features of seventh pandemic strains, and produced cholera toxin and biofilm. PFGE analysis showed that the majority of isolates are clonal and belong to fingerprint pattern A; however, pattern B is unrelated and patterns C and D are distinct, suggesting considerable diversity in the genomic content among them. These data thus show that isolates from Silvassa are genetically diverse and that Haitian ctxB and hybrid phenotypes are undergoing global dissemination.

Asunto(s)

Toxina del Cólera/genética , Cólera/microbiología , Vibrio cholerae O1/genética , Vibrio cholerae O1/fisiología , Adhesinas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Biopelículas/crecimiento & desarrollo , Cólera/epidemiología , Toxina del Cólera/metabolismo , Dermatoglifia del ADN , Electroforesis en Gel de Campo Pulsado , Genes Reguladores , Variación Genética , Islas Genómicas , Genotipo , Humanos , India/epidemiología , Epidemiología Molecular , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/aislamiento & purificación , Factores de Virulencia/genética

RESUMEN

Food-handlers with poor personal hygiene working in food-service establishments could be potential sources of infection due to pathogenic organisms. In May 2011, a cross-sectional study was undertaken to determine the prevalence of bacteria and intestinal parasites among food-handlers working with Cuban health personnel in Haiti. Stool specimens were collected from 56 food-handlers and samples were examined using standard procedures. Of the food handlers, 26.8% had one bacterial or intestinal parasite. The most prevalent species of organism found were Blastocystis spp. (9%), followed by Vibrio cholerae O1 serotype Ogawa, Aeromonas spp. and Giardia intestinalis, each one with 4%. The prevalence of intestinal parasites was 19.7%. Five out of 56 food handlers had diarrhea at the time the study was conducted. It was found that there was a lower prevalence of V. cholerae O1 serotype Ogawa in comparison to intestinal parasites. The study highlights the importance of the precautions that must be taken in cholera-affected countries by medical teams and their organizations, with emphasis on the preparation, processing, and serving of meals. The recommendation is to intensify continuing education programs, periodical laboratory examinations to detect carriers and food-handlers reporting sick, and to observe strict adherence to hygienic food-handling practices. In addition, food handlers with diarrhea should refrain from preparation or delivery of food.

Asunto(s)

Cólera/microbiología , Culinaria , Servicio de Alimentación en Hospital , Parasitosis Intestinales/parasitología , Vibrio cholerae O1/aislamiento & purificación , Adulto , Blastocystis/genética , Blastocystis/aislamiento & purificación , Estudios Transversales , Femenino , Servicio de Alimentación en Hospital/normas , Giardia lamblia/genética , Giardia lamblia/aislamiento & purificación , Haití , Personal de Salud , Humanos , Higiene/normas , Masculino , Prevalencia , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/genética , Recursos Humanos , Adulto Joven

RESUMEN

Introducción: la re-emergencia de cólera en Haití estableció un nuevo reservorio para el incremento de la séptima pandemia. Esto provocó su diseminación a República Dominicana y a otros países de la región del Caribe, como Cuba y México.Objetivo: estudiar la susceptibilidad antimicrobiana de aislamientos de Vibrio cholerae O1, serotipo Ogawa, biotipo El Tor aisladas de pacientes durante el evento epidemiológico de cólera ocurrido en Cuba entre junio de 2012 y agosto de 2013.Métodos: se realizó el estudio de la susceptibilidad antimicrobiana in vitro en 144 aislamientos de V. cholerae, mediante el método de Bauer-Kirby frente a nueve antimicrobianos: ampicilina, sulfonamida, trimetoprim/sulfametoxazol, cloranfenicol, tetraciclina, doxiciclina, azitromicina, ciprofloxacina y gentamicina, según las normas del Instituto de Estándares de Laboratorio Clínico de los Estados Unidos de América.Resultados: el total de los aislamientos resultaron resistentes al trimetoprim-sulfametoxazol; el 98,7 % lo fue a la sulfonamida y el 90,3 % a la ampicilina. Se obtuvieron valores de sensibilidad intermedia para ciprofloxacina (30,6 %) y cloranfenicol (27,1 %). Se apreciaron niveles de sensibilidad superior al 92 % a los antimicrobianos de primera línea en el tratamiento de la enfermedad (doxiciclina, tetraciclina y azitromicina), así como también a la gentamicina. No se observaron cepas multirresistentes.Conclusiones: los datos aportados por este trabajo demuestran la efectividad in vitro de los antimicrobianos utilizados en el tratamiento la enfermedad diarreica aguda causada por V. cholerae en Cuba(AU)

Asunto(s)

Pruebas Antimicrobianas de Difusión por Disco/métodos , Cólera/tratamiento farmacológico , Antiinfecciosos/uso terapéutico , Vibrio cholerae O1/aislamiento & purificación , Cuba

RESUMEN

Introducción: la re-emergencia de cólera en Haití estableció un nuevo reservorio para el incremento de la séptima pandemia. Esto provocó su diseminación a República Dominicana y a otros países de la región del Caribe, como Cuba y México. Objetivo: estudiar la susceptibilidad antimicrobiana de aislamientos de Vibrio cholerae O1, serotipo Ogawa, biotipo El Tor aisladas de pacientes durante el evento epidemiológico de cólera ocurrido en Cuba entre junio de 2012 y agosto de 2013. Métodos: se realizó el estudio de la susceptibilidad antimicrobiana in vitro en 144 aislamientos de V. cholerae, mediante el método de Bauer-Kirby frente a nueve antimicrobianos: ampicilina, sulfonamida, trimetoprim/sulfametoxazol, cloranfenicol, tetraciclina, doxiciclina, azitromicina, ciprofloxacina y gentamicina, según las normas del Instituto de Estándares de Laboratorio Clínico de los Estados Unidos de América. Resultados: el total de los aislamientos resultaron resistentes al trimetoprim-sulfametoxazol; el 98,7 por ciento lo fue a la sulfonamida y el 90,3 por ciento a la ampicilina. Se obtuvieron valores de sensibilidad intermedia para ciprofloxacina (30,6 por ciento) y cloranfenicol (27,1 por ciento). Se apreciaron niveles de sensibilidad superior al 92 por ciento a los antimicrobianos de primera línea en el tratamiento de la enfermedad (doxiciclina, tetraciclina y azitromicina), así como también a la gentamicina. No se observaron cepas multirresistentes. Conclusiones: los datos aportados por este trabajo demuestran la efectividad in vitro de los antimicrobianos utilizados en el tratamiento la enfermedad diarreica aguda causada por V. cholerae en Cuba(AU)

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Introduction: re-emergence of cholera in Haiti created a new reservoir for the increase of the seventh pandemic. This resulted in its spread to the Dominican Republic and other Caribbean countries, such as Cuba and Mexico. Objectives: study the antimicrobial susceptibility of isolates of Vibrio cholerae O1, Ogawa serotype, El Tor biotype, obtained from patients during the cholera epidemiological event occurring in Cuba from June 2012 to August 2013. Methods: a study was conducted of 144 V. cholerae isolates using the Bauer-Kirby method to determine in vitro susceptibility to nine antimicrobials: ampicillin, sulfonamide, trimethoprim/sulfamethoxazole, chloramphenicol, tetracycline, doxycycline, azithromycin, ciprofloxacin and gentamicin, in compliance with standards from the U.S. Clinical and Laboratory Standards Institute. Results: all isolates were resistant to trimethoprim/sulfamethoxazole; 98.7 percent to sulfonamide and 90.3 percent to ampicillin. Intermediate sensitivity values were obtained for ciprofloxacin (30.6 percent) and chloramphenicol (27.1 percent). Sensitivity levels above 92 percent were found for first-line antimicrobials (doxycycline, tetracycline and azithromycin), as well as gentamicin. Multi-drug resistant strains were not found. Conclusions: results reveal the effectiveness in vitro of the antimicrobials used in Cuba to treat acute diarrheal disease caused by V. cholerae(AU)

Asunto(s)

Farmacorresistencia Microbiana , Vibrio cholerae O1/aislamiento & purificación , Pruebas de Sensibilidad Microbiana/métodos , Cuba , Antiinfecciosos/uso terapéutico

RESUMEN

UNLABELLED: An outbreak of cholera occurred in 1991 in Mexico, where it had not been reported for more than a century and is now endemic. Vibrio cholerae O1 prototype El Tor and classical strains coexist with altered El Tor strains (1991 to 1997). Nontoxigenic (CTX(-)) V. cholerae El Tor dominated toxigenic (CTX(+)) strains (2001 to 2003), but V. cholerae CTX(+) variant El Tor was isolated during 2004 to 2008, outcompeting CTX(-) V. cholerae. Genomes of six Mexican V. cholerae O1 strains isolated during 1991 to 2008 were sequenced and compared with both contemporary and archived strains of V. cholerae. Three were CTX(+) El Tor, two were CTX(-) El Tor, and the remaining strain was a CTX(+) classical isolate. Whole-genome sequence analysis showed the six isolates belonged to five distinct phylogenetic clades. One CTX(-) isolate is ancestral to the 6th and 7th pandemic CTX(+) V. cholerae isolates. The other CTX(-) isolate joined with CTX(-) non-O1/O139 isolates from Haiti and seroconverted O1 isolates from Brazil and Amazonia. One CTX(+) isolate was phylogenetically placed with the sixth pandemic classical clade and the V. cholerae O395 classical reference strain. Two CTX(+) El Tor isolates possessing intact Vibrio seventh pandemic island II (VSP-II) are related to hybrid El Tor isolates from Mozambique and Bangladesh. The third CTX(+) El Tor isolate contained West African-South American (WASA) recombination in VSP-II and showed relatedness to isolates from Peru and Brazil. Except for one isolate, all Mexican isolates lack SXT/R391 integrative conjugative elements (ICEs) and sensitivity to selected antibiotics, with one isolate resistant to streptomycin. No isolates were related to contemporary isolates from Asia, Africa, or Haiti, indicating phylogenetic diversity. IMPORTANCE: Sequencing of genomes of V. cholerae is critical if genetic changes occurring over time in the circulating population of an area of endemicity are to be understood. Although cholera outbreaks occurred rarely in Mexico prior to the 1990s, genetically diverse V. cholerae O1 strains were isolated between 1991 and 2008. Despite the lack of strong evidence, the notion that cholera was transmitted from Africa to Latin America has been proposed in the literature. In this study, we have applied whole-genome sequence analysis to a set of 124 V. cholerae strains, including six Mexican isolates, to determine their phylogenetic relationships. Phylogenetic analysis indicated the six V. cholerae O1 isolates belong to five phylogenetic clades: i.e., basal, nontoxigenic, classical, El Tor, and hybrid El Tor. Thus, the results of phylogenetic analysis, coupled with CTXϕ array and antibiotic susceptibility, do not support single-source transmission of cholera to Mexico from African countries. The association of indigenous populations of V. cholerae that has been observed in this study suggests it plays a significant role in the dynamics of cholera in Mexico.

Asunto(s)

Cólera/epidemiología , Enfermedades Endémicas , Variación Genética , Filogenia , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/genética , Toxina del Cólera/metabolismo , Genoma Bacteriano , Humanos , México/epidemiología , Epidemiología Molecular , Análisis de Secuencia de ADN , Vibrio cholerae O1/aislamiento & purificación

RESUMEN

The first week of September 2013, the National Epidemiological Surveillance System identified two cases of cholera in Mexico City. The cultures of both samples were confirmed as Vibrio cholerae serogroup O1, serotype Ogawa, biotype El Tor. Initial analyses by PFGE and by PCR-amplification of the virulence genes, suggested that both strains were similar, but different from those previously reported in Mexico. The following week, four more cases were identified in a community in the state of Hidalgo, located 121 km northeast of Mexico City. Thereafter a cholera outbreak started in the region of La Huasteca. Genomic analyses of the four strains obtained in this study confirmed the presence of Pathogenicity Islands VPI-1 and -2, VSP-1 and -2, and of the integrative element SXT. The genomic structure of the 4 isolates was similar to that of V. cholerae strain 2010 EL-1786, identified during the epidemic in Haiti in 2010.

Asunto(s)

Técnicas de Tipificación Bacteriana , Cólera/microbiología , ADN Bacteriano/química , Genoma Bacteriano , Análisis de Secuencia de ADN , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cólera/epidemiología , ADN Bacteriano/genética , Brotes de Enfermedades , Femenino , Orden Génico , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Sintenía , Vibrio cholerae O1/genética , Vibrio cholerae O1/fisiología , Adulto Joven

RESUMEN

Cholera still continues to be an important cause of human infection, especially in developing countries that lack access to safe drinking water and proper sanitation. In the present study, we report the emergence of new variant form of V. cholerae O1 El Tor biotype with a novel mutation in ctxB in strains isolated from various outbreaks during 2010-2014 in Belgaum situated in north-west Karnataka, India. A total of 14 occurrences of cholera were documented from Belgaum Division of North Karnataka during the 4-year period from 2010 to 2014. All the V. cholerae O1 isolates were subjected to DAMA PCR to detect the three different allelic subtypes of ctxB and PCR-based detection of virulent genes, and subsequently, 14 strains (one strain from each outbreak or sporadic case) were subjected to ctxB gene sequence and pulsed-field gel electrophoresis (PFGE) analysis. A total of 54 V. cholerae O1 strains were obtained of which 21 strains isolated during 2010-2011 had classical ctxB and remaining 33 strains isolated during 2012-2014 belonged to Haitian variant. In the cluster analysis, the PFGE profiles were divided into clades A with and B. Clade A contained eight strains with 94 % similarity and Haitian type of ctxB. Clade B contained six strains and had Haitian type of ctxB except one with classical ctxB. To the best of our knowledge, this is the first report of the Haitian variant of V. cholerae O1 Ogawa causing outbreaks and sporadic cases of cholera in South India.

Asunto(s)

Cólera/epidemiología , Cólera/microbiología , Enfermedades Transmisibles Emergentes , Vibrio cholerae O1/clasificación , Brotes de Enfermedades , Genes Bacterianos , Humanos , India/epidemiología , Filogenia , Vibrio cholerae O1/aislamiento & purificación

RESUMEN

Since the identification of the first cholera case in 2010, the disease has spread in epidemic form throughout the island nation of Haiti; as of 2014, about 700,000 cholera cases have been reported, with over 8,000 deaths. While case numbers have declined, the more fundamental question of whether the causative bacterium, Vibrio cholerae has established an environmental reservoir in the surface waters of Haiti remains to be elucidated. In a previous study conducted between April 2012 and March 2013, we reported the isolation of toxigenic V. cholerae O1 from surface waters in the Ouest Department. After a second year of surveillance (April 2013 to March 2014) using identical methodology, we observed a more than five-fold increase in the number of water samples containing culturable V. cholerae O1 compared to the previous year (1.7% vs 8.6%), with double the number of sites having at least one positive sample (58% vs 20%). Both seasonal water temperatures and precipitation were significantly related to the frequency of isolation. Our data suggest that toxigenic V. cholerae O1 are becoming more common in surface waters in Haiti; while the basis for this increase is uncertain, our findings raise concerns that environmental reservoirs are being established.

Asunto(s)

Cólera/epidemiología , Reservorios de Enfermedades/microbiología , Monitoreo del Ambiente/estadística & datos numéricos , Agua Subterránea/microbiología , Vibrio cholerae O1/aislamiento & purificación , Antibacterianos/farmacología , Cólera/microbiología , Farmacorresistencia Bacteriana , Monitoreo Epidemiológico , Haití/epidemiología , Humanos , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa , Vibrio cholerae O1/efectos de los fármacos , Vibrio cholerae O1/genética , Vibrio cholerae O1/patogenicidad

Asunto(s)

Reservorios de Enfermedades/microbiología , Vibrio cholerae O1/aislamiento & purificación , Microbiología del Agua , Calidad del Agua , Haití , Humanos

RESUMEN

SUMMARY This investigation was undertaken to characterize the prevalence of intestinal Vibrio cholerae in healthcare workers (HCWs) returning from Haiti due to the ongoing cholera epidemic. Eight hundred and fifty asymptomatic HCWs of the Cuban Medical Brigade, who planned to leave Haiti, were studied by laboratory screening of stool culture for V. cholerae. A very low percentage (0.23%) of toxigenic V. cholerae serogroup O1, serotype Ogawa was found. To the best of our knowledge, this study represents the largest reported screening study for V. cholerae infection in asymptomatic HCWs returning from a cholera-affected country. Cholera transmission to health personnel highlights a possible risk of transmitting cholera during mobilization of the population for emergency response. Aid workers are encouraged to take precautions to reduce their risk for acquiring cholera and special care should be taken by consuming safe water and food and practising regular hand washing.

Asunto(s)

Portador Sano/epidemiología , Cólera/epidemiología , Epidemias , Heces/microbiología , Personal de Salud/estadística & datos numéricos , Viaje , Vibrio cholerae/genética , Enfermedades Asintomáticas/epidemiología , Estudios de Cohortes , ADN Bacteriano/análisis , Haití/epidemiología , Humanos , Tamizaje Masivo , Reacción en Cadena de la Polimerasa , Vibrio cholerae/aislamiento & purificación , Vibrio cholerae O1/genética , Vibrio cholerae O1/aislamiento & purificación