scholarly journals Concerning imported cases of cholera in the city of Almaty, Kazakhstan, 2017

2018 ◽  
pp. 83-87 ◽  
Author(s):  
Z. A. Sagiev ◽  
R. S. Musagalieva ◽  
A. A. Abdirasilova ◽  
T. Z. Ayazbaev ◽  
M. M. Kul’baeva ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Genetic ◽  
Laboratory Diagnosis ◽  
Genetic Studies ◽  
Cholera Vibrio ◽  
Group I ◽  
Highly Sensitive ◽  
Imported Cases ◽  
Methodological Guidelines ◽  
The City

In 2017, from October 15 to November 21, 5 cholera cases imported from India – 3 patients and 2 carriers of V. cholerae – were recorded in Almaty. The patients recovered from the disease. Objective of the study was to characterize the imported cases of cholera and investigate the properties of cholera vibrio strains isolated from patients and carriers of V. cholerae. Materials and methods. Revised were the medical records; blood sera, feces from patients and contact persons were assayed. Studied were sensitivity spectrum to antibacterial preparations of isolated V. cholerae strains according to the “Methodological guidelines on laboratory diagnosis of cholera”, dated September 27, 2010; No 252. Epidemiological, microbiological, immunological and molecular-genetic methods were applied for investigation. Results and conclusions. Consequently to molecular genetic studies, genes of specificity, wbeN and toxicity (epidemic significance), ctxA, tcpA were detected in samples from 3 patients and 2 contact persons. The isolated strains were identified as Vibrio cholerae O1 Eltor Inaba in two cases, and in one case – as Vibrio cholerae O1 Eltor Hykoshima, Heiberg group I, toxigenic, hemolysis negative in Greig test, virulent, highly sensitive to ciprofloxacin, doxycilin, erythromycin, tetracycline and moderately sensitive to levomycetin. It was established that the country of export in all the cases was India. Relevant anti-epidemic and preventive measures were undertaken to localize and eradicate the foci in order to prevent possible threat of epidemic spread of infections among the population.

scholarly journals Use of Molecular Genetic Methods for Investigation of Outbreaks of Enterovirus Infection in the Subjects of the Far Eastern Federal District

2016 ◽  
Vol 15 (2) ◽  
pp. 43-47
Author(s):  
L. V. Butakova ◽  
O. E. Trotsenko ◽  
E. Yu. Sapega ◽  
V. O. Kotova ◽  
L. A. Balakhontseva ◽  
...  
Keyword(s):  
Molecular Genetic ◽  
Federal District ◽  
Clinical Samples ◽  
Enterovirus Infection ◽  
Amur Oblast ◽  
Genetic Studies ◽  
Khabarovsk Krai ◽  
Imported Cases ◽  
Far Eastern ◽  
Rural Locality

The results of molecular genetic studies of clinical samples taken from three foci of outbreaks of enterovirus infection, registered on the territory of Khabarovsk Krai and Amur Oblast from 2012 through 2013 were reported. Several strains of enteroviruses were obtained: strains of Coxsackie A-4 and Coxsackie A-16 from De-Kastri rural locality, strains of ECHO-6 from Ust’-Urikma (Amur Oblast) and strains of Coxsackie A-6 from Raichihisnsk (Amur Oblast). Use of molecular genetic methods for investigation of collective morbidity and outbreaks of enterovirus infection help to confirm the identity of enteroviruses, isolated from patients and to identify the imported cases of infection.

The Evolution of Phenotypic Properties and Molecular Genetic Organization of Genomes of Vibrio Cholerae O1 El Tor Variant Strains Isolated from Patients and Environmental Objects in the Caucasus in 1970–1998

2020 ◽  
pp. 56-61
Author(s):  
VN Savelyev ◽  
DA Kovalev ◽  
IV Savelyeva ◽  
TV Taran ◽  
EI Podoprigora ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Molecular Genetic ◽  
Laboratory Diagnosis ◽  
Classical Type ◽  
Phenotypic Properties ◽  
The Caucasus ◽  
Genetic Characteristics ◽  
Environmental Objects ◽  
Vibrio Cholerae O1 ◽  
El Tor

Summary. Introduction: The formation of highly pathogenic strains of Vibrio cholerae resistant to antibiotics determines the pathogenesis, clinical picture, epidemiology, and laboratory diagnosis of cholera. It is necessary to study the structure of the genome of V. cholerae of any serological groups isolated during routine monitoring of environmental objects or patients with acute intestinal infections in order to detect toxigenic genes inherent to epidemic strains of V. cholerae O1. Our objective was to study changes in phenotypic properties and molecular genetic bases of persistence, epidemic and pathogenetic potential of El Tor variant of Vibrio cholerae O1 isolated from patients and environmental objects in the Caucasus in 1970–1998. Materials and methods: We studied phenotypic and molecular genetic characteristics of 32 V. cholerae O1 strains isolated from patients and environmental objects in the Caucasus (1970–1998) using a microbiological assay and PCR test, respectively. Results: We established that the following biotypes of V. cholerae O1 were found in the Caucasus: a) El Tor, ctxA–, and Hly+ nontoxigenic strains of V. cholerae O1, typical in their phenotypic and molecular genetic properties. Their toxigenic potential is represented by exo- and endotoxins different from the enterotoxin of toxigenic V. cholerae; b) toxigenic El Tor, ctxABEL+, rtхC+, and Hly– variant biotypes of V. cholerae O1, typical in their phenotypic, molecular and genetic properties during outbreaks of invasive cholera, producing a CT-2 enterotoxin and containing genes responsible for persistent, pathogenic and pandemic potential, and c) typical in terms of their main phenotypic characteristics but molecularly genetically altered variants (hybrids) of El Tor variant of Vibrio cholerae O1 including El Tor ctxABCL+, rtxC+, Hly–. Conclusions: The main manifestation of evolutionary changes in a typical toxigenic vibrio of the El Tor variant biotype was the replacement of the ctxBEl gene in its genome with the ctxBCL gene encoding the classical type of enterotoxin (CT-1), which significantly increased the persistent, toxic, epidemic, and pandemic potential of genetically modified variants of El Tor biotype Vibrio cholerae. The genome of these strains contains an integrative and conjugative element SXT with genes for antibiotic multiresistance.

scholarly journals RETROSPECTIVE ANALYSIS OF BIOLOGICAL AND MOLECULAR-GENETIC PROPERTIES OF STRAINS - CAUSATIVE AGENTS OF CHOLERA - ISOLATED IN UKRAINE IN 1994 - 2011

2017 ◽  
pp. 49-55
Author(s):  
I. V. Savelieva ◽  
S. N. Tikhonov ◽  
V. N. Saveliev ◽  
D. A. Kovalev ◽  
S. V. Pisarenko ◽  
...  
Keyword(s):  
Retrospective Analysis ◽  
Vibrio Cholerae ◽  
Molecular Genetic ◽  
Test System ◽  
Personal Genome ◽  
International Database ◽  
Cholera Vibrio ◽  
Causative Agents ◽  
Pcr Method ◽  
El Tor

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.

Biochemical studies on the production of neuraminidase by environmental isolates of Vibrio cholerae non-O1 from Bulgaria

2011 ◽  
Vol 57 (7) ◽  
pp. 606-610 ◽  
Author(s):  
Rumyana Eneva ◽  
Stephan Engibarov ◽  
Tanya Strateva ◽  
Radoslav Abrashev ◽  
Ignat Abrashev
Keyword(s):  
Vibrio Cholerae ◽  
Pathogenic Bacteria ◽  
Environmental Isolates ◽  
Anaerobic Conditions ◽  
Temperature Optimum ◽  
Ph Optimum ◽  
Cholera Vibrio ◽  
Key Factor ◽  
Aeration Conditions ◽  
The One

Neuraminidase is a key factor in the infectious process of many viruses and pathogenic bacteria. The neuraminidase enzyme secreted by the etiological agent of cholera — Vibrio cholerae О1 — is well studied in contrast with the one produced by non-O1/non-O139 V. cholerae. Environmental non-O1/non-O139 V. cholerae isolates from Bulgaria were screened for production of neuraminidase. The presence of the neuraminidase gene nanH was detected in 18.5% of the strains. Тhe strain showing highest activity (30 U/mL), V. cholerae non-O1/13, was used to investigate the enzyme production in several media and at different aeration conditions. The highest production of extracellular neuraminidase was observed under microaerophilic conditions, which is possibly related to its role in the infection of intestine epithelium, where the oxygen content is low. On the other hand, this is another advantage of the microbe in such microaerophilic environments as sediments and lake mud. The highest production of intracellular neuraminidase was observed at anaerobic conditions. The ratio of extracellular to intracellular neuraminidase production in V. cholerae was investigated. The temperature optimum of the enzyme was determined to be 50 °C and the pH optimum to be 5.6–5.8.

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