DIAGNOSTIC CHARACTERISTICS OF A LATEX ANTIGEN HELICOBACTER TEST-SYSTEM

Purpose: The study of operation diagnostic characteristics of a newly constructed helicobacter test-system which is designed to determine the total antibodies in the blood serum in volumetric agglomeration reaction.Materials and methods: Blood sera of 224 gastroenterological patients were studied with the help of diagnostic system constructed. Commercial immune-enzyme blood assay systems were used to be the referent method.Results: Diagnostic operation characteristics of a latex antigen helicobacter test-system were determined with the help of referent serological diagnostic methods. At the cut-off point 1:160 the sensitivity, specificity and diagnostic effectiveness are 94,9%, 79,3% и 88,2%, respectively.Summary: The cut-off point 1:160 is shown to be used as a diagnostic threshold

SEROEPIDEMIOLOGICAL RESEARCH AND ANALYSIS OF SOME EPIDEMIOLOGICAL PRE-CONDITIONS TO CIRCULATION OF THE VIRUS OF TICK-BORNE ENCEPHALITIS ОN THE TERRITORY OF THE ROSTOV REGION

Purpose: To study the rate of infection of population of the Rostov region by the virus of tick-borne encephalitis (TVE) and in analyzing the pre-conditions of its possible circulation.Materials and methods: Data from relevant literature sources, results of regional entomological study, blood sera samples from donors of the Rostov regions and patients of infectious and neurologic units at the Rostov hospitals in 2009-2012 have 39Медицинский вестник Юга России ОРИГИНАЛЬНЫЕ СТАТЬИbeen used as the material for analysis. We have used methods of scientific and informational search, as well as analytical and immunoserological methods.Results: Results of the study have revealed the existence of Ig G class antibodies to the etiological agent of encephalitis in donor blood sera on the territory of five areas and two cities. In blood sera of the patients of neurologic and infectious units of the Rostov hospitals the Ig G antibodies to the virus of tick-borne encephalitis haven’t been found. Existence of favorable conditions as well as forest resources along with the prevalence of I. ricinus tick species and animals - potential reservoirs of the virus - serve as prerequisites for virus circulation in northern and northwestern areas of the Rostov region.Summary: For determination of virus circulation there is will be necessary to study the existence of the virus of tick-borne encephalitis in vectors-ticks and their possible hosts

DEVELOPMENT OF SPATIAL ANALYSIS TECHNIQUES FOR IDENTIFICATION OF "RISK AREAS" IN CASE OF EXTERNAL THREATS REALIZATION AS REGARDS SANITARY AND EPIDEMIOLOGICAL WELLFARE

Objective of the study was to develop the methodology for identification of administratively independent areas under potential risk of “external” epidemiological threat realization, by the example of cholera.Materials and methods. Analysis was conducted using free software package with open source code (QGIS 2.8 and GRASS GIS 7.0) on the basis of the data received from Rosgranitsa and the Federal State Statistics Service. The construction of risk cartogram was performed on the base of Euclidean distance and estimation of nuclear density.Results and conclusions. In accordance with the obtained results, the GIS containing information about the checkpoints on the Russian border, settlements, roads and railway lines was worked out. The method of identification of risk areas due to importation of infectious diseases based on the cholera model has been developed, and the total area of such territories was less than 1 % of the total area of the country. It was found that in some cases the risk area is located at a certain distance from the checkpoint, but the existence of checkpoint does not lead to the formation of risk areas. The developed GIS is available on the geo-information portal of FGHI Rostov-on-Don Research Anti-Plague Institute of Rospotrebnadzor

ECOLOGICAL AND EPIDEMIOLOGICAL ASPECTS OF WEST NILE FEVER IN THE ROSTOV REGION

RETRACTEDPurpose: Th e study of the West Nile Fever (WNF) with the estimation of results of ecological/epizootological monitoring and epidemic manifestations of infection.Materials and methods: investigations for the presence of antigen of WN virus were carried out on 5754 specimen (4187 samples of brain suspensions) of birds belonging to 90 species, 15 orders; 4153 specimen (1038 samples of brain suspensions) of 17 species of mammals; 46113 specimen (2081) of 18 species of mosquitoes; 13883 specimen (1588) of imago ticks of six species, and others (2001-2013). Methods used: enzyme-linked immunosorbent assay, epidemiological analysis.Results: the territories of risk for WNF were defi ned with regard to bird ecology, fauna of mosquitoes of Culicidae family was characterized, the ecological linkages of WN virus with birds, mosquitoes and mammals were defi ned. Th e area of habitation of West Nile (WN) virus was determined. Epizootological/epidemiological zoning of the Rostov Region was carried out with identifi cation of territories, diff ering by the degree of risk of population infection with WN virus.Summary: Th e results obtained can serve the evidence of formation of natural and anthropurgic foci of WNF

West Nile Fever in the Rostov Region: Ecological and Epidemiological Peculiarities of the Outbreak in 2010

This paper describes the outbreak of West Nile fever in the Rostov Region in 2010 and evaluates its ecological and epidemiological peculiarities. From 15th of July till 22nd of September 2010, detected were the 64 cases (1, 4800/0000) of the disease, which were characterized by vector-born mechanism of transmission. Peak of morbidity coincided with mass breeding of Culicidae, increase in the number of Culex mosquitoes, and reoccurring growth of Aedes mosquito population. Diffuse type of the epidemiological process, higher rates of the cases among urbanites, infected in the country-side area, were the characteristic features of that outbreak. West Nile virus antigen was detected by means of IFA in samples taken from An. maculipennis and Cx. pipiens mosquitoes, wild and synanthropic birds, Rh. rossicus ticks, house and wood mice, which facilitates identification of the core factors for the agent circulation and West Nile fever natural focus formation

Cloning and Expression of <i>ace</i> Gene of <i>Vibrio cholerae</i> in <i>Escherichia coli</i>

Accessory cholera enterotoxin (ace) gene of Vibrio cholerae, amplified by PCR, is cloned into the BamHI-HindIII sites using plasmid pQE30. Expression of ace gene is under the control of T5 promotor. The Escherichia coli strain M15[pREP4]pAce90 (KM 194), containing recombinant plasmid, is an active producer of 6His-Ace protein, which possesses biological activity in the models of suckling mice and causes accumulation of fluid in the intestine. The product is contained in inclusion bodies found in the cells of coliform bacterium. The engineered producer strain can be used to obtain Ace preparations with a view to study its significance as pathogenicity factor in cholera vibrio

EFFECT OF ANTIBACTERIAL PREPARATIONS ON VIBRIO CHOLERAE EL TOR BIOFILMS

Aim. Study the effect of antibacterial preparations on biofilms of Vibrio cholerae El Tor. Materials and methods. Sensitivity of V. cholerae El Tor (6 strains) to various concentrations of antibacterial preparations (doxycycline, tetracycline, levomycetin, rifampicin, gentamycin, ceftazidime) was determined (MD 4.2.2495-09). Transmission electron microscopy was used for visualization of the effect of preparations on biofilms. Results. The values of minimal inhibiting concentrations of antibacterial preparations against biofilms have increased by 5 - 100 times compared with plankton cultures. Certain smoothing of strands between the bacterial cell and substrate, alteration of vibrios’ form, reduction of electron density of the matrix with an increase of its transparency were observed during electron-microscopy of the effect of antibacterial preparations on the biofilm. Conclusion. Study of the effect of antibacterial preparations on biofilms could increase effectiveness of rational antibiotics therapy of infections by selection of preparations that disrupt functioning of microbial communities

BIODIVERSITY AND ANTIBIOTICS RESISTANCE OF OPPORTUNISTIC PATHOGENIC ENTEROBACTERIA ISOLATED FROM SURFACE RESERVOIRS OF ROSTOV-ON-DON

Aim. Study biodiversity, sensitivity/resistance to antibacterial preparation (ABP) of opportunistic microorganisms of Enterobacteriaceae family isolated from surface reservoirs of Rostov-on-Don in 2014 - 2016. Materials and methods. Determination of genus and species membership of enterobacteria was carried out by the results of a complex of biochemical tests using MALDI Biotyper program-apparatus unit. Sensitivity to ABP was determined by serial dilution method. Results. 468 strains of opportunistic and pathogenic enterobacteria were isolated during the study. 20 genera, 33 species of microorganisms were identified. (37.0%), Klebsiella (13.2%), Citrobacter (8.0%) predominated. 8.5% of the strains isolated in 2014 were sensitive to ABP, 5.2% - in 2015; strains sensitive to ABP were not detected in 2016. The number of polyresistant isolates has increased during the last 3 years: 40.7% strains in 2014,60.1 % in 2015. 80,0% in 2016. Ceftriaxone, gentamycin and ciprofloxacin had high activity against the isolated enterobacteria. The highest resistance was documented against ampicillin, nalidixic acid, nitro-furane, co-trimoxazole. Conclusion. The data obtained allow to evaluate the dynamics of increase of polyresistant strains of enterobacteria isolated from surface reservoirs

TYPING OF VIBRIO CHOLERAE NON O1/NON O139 STRAINS, ISOLATED IN ROSTOV REGION IN 2014

Aim. Comparative study of antibiotics resistance and VNTR-typing of Vibrio cholerae non O1/ non O139 strains, isolated on the territory of Rostov region in 2014. Materials and methods. Antibioticogramms of strains were determined by serial dilution method in dense nutrient medium according to MG 4.2.2495-09 (2009). Pheno-, sero- and VNTR-typing was carried out by conventional methods. Results. The studied strains belonged to V. cholerae species, did not agglutinate with O1 and O139 sera, were atoxigenic, hemolysis-positive, did not contain genes of cholera toxin and toxin-coregulating pili ofadhesion, contained genes ofhemagglutinin/protease, protease PrtV, collagenase, cytotonic factor Cef, outer membrane protein OmpW, tol- and vps-clusters, regulatory genes toxR and hapR. Antibioticogramms of the strains have shown the presence of cultures, resistant to ampicillin, ceftazidime, furazolidone, trimethoprim/sulfamethoxazole with intermediate resistance to streptomycin, kanamycin, gentamycin, amikacin, netilmicin. Approximately 20% of isolates had multiple drug resistance. Data of VNTR- and geno-typing confirmed a possibility of water transmission route of the infection. Conclusion. Execution of monitoring of cultures from environmental samples is necessary for timely detection of genetic characteristics, antibiotics resistance