[ACTUAL PROBLEMS OF EPIDEMIOLOGIC CONTROL, LABORATORY DIAGNOSTICS AND PROPHYLAXIS OF CHOLERA IN RUSSIAN FEDERATION].

Main problems of system of epidemiologic control for cholera active in Russian Federation, as well as laboratory diagnostics and vaccine prophylaxis of this especially dangerous infection, that had emerged in the contemporary period of the ongoing 7th pandemic of cholera, are discussed. Features of the genome of natural strains of Vibrio cholerae of El Tor biovar, that possess a poten- tial epidemic threat, as well as problems, that have emerged during isolation of these strains from samples of water of surface water bodies during their monitoring, are also examined. The main direction of enhancement of the system of epidemiologic control for cholera consist in develop- ment of a new algorithm of differentiation of administrative territories of Russian Federation by types of epidemic manifestations, as well as optimization of monitoring of environment objects. Integration of modern highly informative technologies into practice, as well as development of new generation diagnostic preparations based on DNA-chips and immunechips is necessary to increase effectiveness of the conducted operative and retrospective diagnostics in the contemporary period. Creation of national cholera vaccine, ensuring simultaneous protection from cholera causative agents of both O1 and O139 serogroups, is also required.

[Epidemiological Surveillance of Cholera in Russia During the Period of the Seventh Pandemic].

In this work basic stages of formation of the epidemiological surveillance of cholera in Russia are described. In 1990-s for the first time zoning by epidemic manifestations of cholera was carried out at the level of subjects forming parts of Russia and other Republics of the Soviet Union with the introduction of differential tactics of epidemiological surveillance. Improvement of epidemiological surveillance of cholera was aimed at harmonization with the IHR (2005), integration of epidemiological surveillance of cholera and social-hygienic monitoring of water objects of I and II categories. Characterization of isolated Vibrio cholerae strains (1990-2014) on the genomic basis determined the emergence of new VNTR-genotypes of V. cholerae O1 ctxAB+ tcpA+, responsible for outbreaks, simultaneously with isolation of V. cholerae 01 ctxAB-tcpA-strains during monitoring of environmental objectsfor cholera. A viewpoint is considered of the beginning of the eighth cholera pandemic in the context of emergence of V. cholerae El Tor strains with CTXφ prophage carrying ctxB gene of cholera toxin of classical biovar. Main directions offurther enhancement ofepidemiological surveillance include the study of basic data structures used in the epidemiological surveillance system, the use of zoning of municipal units offederal subjects with corresponding surveillance tactics and expected economic effect.

[DETERMINATION OF TYPES OF EPIDEMIC MANIFESTATIONS OF CHOLERA IN REGIONS OF THE CRIMEA FEDERAL DISTRICT (REPUBLIC OF CRIMEA)].

The aim of the study was determination of the type of epidemic manifestations of cholera in the Republic of Crimea based on evaluation of epidemic manifestations of cholera risk of introduction and spread of the infection. It was concluded, that, based on the cholera outbreaks, that had taken place, contamination of surface water bodies (fresh and sea) and sewage by Vibrio cholerae O1 ctxA+ and Vibrio cholerae O1 ctXA- potential epidemic danger of introduction of the infection by various types of international transport, population migration, the presence of epidemiologic risk in realization of water pathway of transmission of cholera causative agent and several other social conditions, the Republic of Crimea remains in the group of territories of type I by epidemic manifestations of cholera.

[Novel diagnostic kit on the basis of stained polymeric carriers for epidemiologic surveillance in natural foci of Crimean-Congo hemorrhagic fever].

AIM: To study diagnostic value of developed antigenic polymeric diagnostic kit for epidemiologic surveillance in natural foci of Crimean-Congo hemorrhagic fever (CCHF) in South federal district. MATERIALS AND METHODS: Novel antigenic diagnostic kit on the basis of polymeric microspheres for reaction of volume agglomeration was developed. The kit is designed for detection of virus-specific antibodies in human serum and in serum of agricultural animals. RESULTS: Laboratory and field trials of the kit showed its high diagnostic potency, it was included in methodical recommendations "Organization and accomplishment of measures against Crimean-Congo hemorrhagic fever on the territory of its natural foci in Russia". Use of antigenic polymeric kit for epidemiological surveillance allows for more complete and systemic understanding of CCHF epidemic process. CONCLUSION: At present, the diagnostic kit is successfully used, alongside with ELISA and PCR, on different levels of epidemiologic surveillance for CCHF in Rostov region.

[Vibrio cholerae serogroups O1 and O139: susceptibility to antibiotics during 7th cholera pandemic].

The review presents data on circulation of antibiotic resistant and susceptible strains of Vibrio cholerae serogroups O1 and O139 isolated from cholera patients and healthy persons as well as from the environment, in Asia, Africa, Australia, and Europe (including New Independent States) during 7th cholera pandemic.

[Cholera caused by Vibrio cholerae O1 ctxAB- tcpA+].

Results of analysis of cholera outbreak during which V. cholerae O1 biovar El-Tor ctxAB- tcpA+ was isolated from 2 patients and 30 carriers are presented. Epidemic was caused by contamination of water source and water route of transmission. Strains identical to ones detected in humans were isolated from water of surface well in zone of water intake. Genome and VNTR-analysis of ctxAB- tcpA+ vibrios that caused outbreak in Rostov region in 2005 showed that they differed from ctxAB- tcpA- and ctxAB- tcpA+ vibrios isolated previously during and beyond of outbreaks from patients, carriers and environment and formed separate group with certain genotype. These results confirms conclusions of epidemiological analysis about imported cause of recent outbreak.

[Cholera at the beginning of the XXI century. Prognosis].

The worldwide epidemiological situation in cholera El Tor at the beginning of this century is presented; among its characteristic features are continued extensive epidemics and outbreaks in African and Asian countries with cases of import of this infection to other continents. Outbreaks caused by a new variant of the infective agent of cholera, Vibrio cholerae O139, are still registered at limited territories in the countries of South-East Asia. In some CIS countries (Azerbaijan, Kazakhstan and Russia) unstable situation in cholera is still preserved due to cases of infection import mainly from Asian countries, as well as to the isolation of epidemically insignificant haemolysin-positive and haemolysin-negative V. cholerae O1 and O139, containing no ctx and tcpA genes, from surface water reservoirs and other environmental objects. In Russia prognosis for cholera is still unfavorable.

[Cholera in Kazan. Organization and implementation of cholera control interventions]. / Kholera v Kazani. Organizatsiia i provedenie protivokholernykh meropriiatii.

Data on emergent epidemiological analysis of the cholera outbreak in Kazan are presented. A version of the cholera focus emergence was confirmed, namely water route of transmission as a result of bathing in a water reservoir where sewage waters had penetrated. The outbreak had local and acute character. The complex of cholera control interventions aimed at localization and liquidation of the focus proved to be effective.

[Characterization of Vibrio cholerae eltor in the city of Kazan in 2001]. / Kharakteristika kholernykh vibrionov él'tor, vydelennykh v g. Kazan' v 2001 g.

Information on V. cholerae eltor isolated in the focus of cholera in Kazan in 2001 at different periods of the outbreak is presented. The identity of strains isolated from patients, vibriocarriers and environmental objects, including their antibioticograms (sensitivity to cyprofloxacin and resistance to trimethoprim--sulfamethoxazole, streptomycin, furazolidone and nalidixic acid, which may be regarded as markers), is shown. Variable tandem repetitions in the DNA of 30 isolates strains of different origin have been determined. The results of this determination make it possible to classify all these strains as one genotype, which confirms the suggestion on the circulation of one subclone of the infective agent of cholera in the focus. As revealed in this investigation, the isolated strains are labile with respect to diagnostic phage eltor, while ctx+ strains are resistant to phage eltor ctx+.

[Crimean hemorrhagic fever in the Rostov region: epidemiological zoning and the activity of natural foci]. / Krymskaia gemorragicheskaia likhoradka v Rostovskoi oblasti: épidemiologicheskoe raionirovanie i aktivnost' prirodnogo ochaga.

The epidemiological zoning of the territory of the Rostov region has been made with the use of the epidemic process patterns and the data indicating the links between the landscape and the natural focus of infection. The spread of infected ticks has been established. The participation of several carrier species in the circulation of Crimean-Congo haemorrhagic fever virus has been confirmed. The mosaic character of their distribution and different levels of their contamination is of great prognostic importance. These data will be used for the improvement of epidemiological surveillance in working out the tactics of epizootological surveys and organization of prophylactic measures.

[Experimental evaluation of efficacy of Lactobacilli in prophylaxis and treatment of cholera]. / Eksperimental'naia otsenka éffektivnosti laktobatsill dlia profilaktiki i lecheniia kholery.

Investigations on experimental models of cholera ("sealed" mice and suckling rabbits) demonstrated that previous daily oral administration of the ferment culture of Lactobacillus acidophilus BKM B-2020[symbol: see text] in a dose of 3.0 x 10(8) microbial cells/ml daily for 5-7 days prevented to the development of Vibrio cholerae infection. The curative effect observed after 3 administrations of lactobacilli within 48 hours after infection with V. cholerae was registered in 50% of cases. This strain of lactobacilli was found to be suitable for use as the basis component of probiotic, an additional remedy for the prophylaxis and treatment of cholera.

[Crimean-Congo hemorrhagic fever in Rostov Province: the epidemiological characteristics of an outbreak]. / Krymskaia-Kongo gemorragicheskaia likhoradka v Rostovskoi oblasti: épidemiologicheskie osobennosti vspyshki.

The results of the epidemiological analysis of the outbreak of hemorrhagic fever which was caused by Crimean-Congo hemorrhagic fever virus and occurred during the period of July 3-19, 1999, in the Oblivskaya district of Rostov Province are presented. The specific epidemiological features of the outbreak have been determined. The possible versions of the appearance of the focus of infection and the role of Ixodes ticks in the circulation of the infective agent are discussed.

[Database on nucleotide sequences used as primers of microorganisms]. / Baza dannykh o nukleotidnykh posledovatel'nostiakh, ispol'zuemykh v kachestve praimerov mikroorganizmov.

The data base (DB) "Primers of microorganisms" for the accumulation and systematization of information on oligonucleotide sequences, used as primers in polymerase chain reaction, has been created. This DB includes data on primers for the laboratory diagnostics of 20 bacterial genera (Aerococcus, Aeromonas, Bartonella, Borrelia, Burkholderia, Chlamydia, Clostridium, Corynebacterium, Escherichia, Francisella, Helicobacter, Legionella, Listeria, Mycobacterium, Mycoplasma, Salmonella, Shigella, Staphylococcus, Vibrio, Yersinia) and 6 viral families (Arenaviridae, Flaviviridae, Hepadnaviridae, Herpesviridae, Picornaviridae, Retroviridae). DB contains data on 145 pairs of primers and 530 bibliographic sources. The retrospective depth of DB is 10 years (1987-1996), and it is replenished as new Russian and foreign documented sources of information arrive.

[The characteristics of the current stage in the development of the 7th cholera pandemic]. / Kharakteristika sovremennogo étapa v razvitii 7 pandemii kholery.

The state and tendencies in the development of the epidemiological situation in cholera in the world (1961-1996) are evaluated. As revealed in this investigation, at the modern stage the development of the 7th pandemic characterized by the formation of stable and temporary endemic foci in a number of countries of Asia, Africa, Central and South America and by the import of cholera from these foci to different countries of the world, including the CIS countries and Russia. The "trigger mechanism" of epidemic manifestations in Russia is discussed, in particular the epidemic of 1994 in Dagestan used as an example. Prognostication is made on the basis of the analysis of the epidemiological situation.

[An operative analysis of the cholera epidemic in the Republic of Dagestan using a computer database]. / Operativnyi analiz épidemii kholery v Respublike Dagestan s ispol'zovaniem komp'iuternoi bazy dannykh.

The epidemiological information on cholera epidemic in Daghestan during the period of June 6 to October 21, 1994, based on the data obtained from 2,327 patients and Vibrio carriers in 184 settlements of 27 regions, 8 towns and 1 housing estate, was collected, systematized and analyzed with the use of the data base (DB). The use of DB made it possible to carry out the surveillance of the level of and dynamics of morbidity and infections rates, to determine the territories of risk, the age and social groups of risk, the active routes and factors of transmission. DB may be used for analyzing of operative and current epidemiological information in cholera and other infections.

[Cholera in the Republic of Dagestan]. / Kholera v Respublike Dagestan.

Cases of cholera were registered in Daghestan in all pandemics with the exception of the fourth one. For the first time the import this infection by pilgrims returning from their hajj by motor transport and traveling through the countries of southwest Asia was registered. 184 settlements of 27 regions, 8 towns and 1 housing estate were involved in the epidemic process, the number of registered cholera cases and Vibrio carriers being 2,327. High contamination rates were detected in regions situated in different geographical zones. Everyday contacts and the alimentary route were the main routes of transmission during this epidemic, while the role of the water route was considerably less important.

[Cholera in Makhachkala during the 1994 epidemic]. / Kholera v Makhachkale v period épidemii 1994 g.

During the period of epidemic in the Daghestan 51 patients and 27 Vibrio carriers were detected in Makhachkala. A considerable proportion (30.7%) of cholera cases caused by infection imported from regions, unfavorable with respect to cholera, in the presence of pronounced migration of the population was registered. The role of different transmission routes in cases of cholera was as follows: day contacts were responsible for 43.3%, the alimentary route for 28.4% and the water route for 14.9% of cases. The epidemic situation was characterized by a mild and prolonged type of the epidemic process. Mass diseases were prevented by a complex of cholera control measures, among them the emphasis was made on various limitations and prophylactic measures aimed at the rupture of the transmission routes of V. cholerae.

[The epidemiological characteristics of cholera in the Republic of Dagestan. An assessment of the epidemic-control measures]. / Epidemiologicheskie osobennosti kholery v Respublike Dagestan. Otsenka nekotorykh protivoépidemicheskikh meropriiatii.

Retrospective analysis of epidemic cholera manifestations was made in Daghestan using the data of operative epidemic analysis of the break in 1994. Unexpected prolongation of epidemic process of cholera for Daghestan, which was imported by pilgrims from Southern-Western Asia, has been shown using climate-geographical social-demographical and sanitary-hygienic peculiarities. Common laws of development of epidemic complications were demonstrated, as well as the main ways of infection transmission of great number of Daghestan settlements in epidemic process. The importance of antiepidemic means and significant role of created specialized antiepidemic groups have been emphasized in rapid carrying out of means in infection focus, including massive investigation of people in settlements.

[The epidemic situation re: cholera in the world: a morbidity analysis and trends]. / Epidemicheskaia situatsiia po kholere v mire: analiz i tendentsiia zabolevaemosti.

The analysis of cholera morbidity throughout the world over the period of 1988-1992 indicates the existence of a tendency towards an increase in morbidity due to epidemic outbreaks in the countries of South and Central America and in Africa. Using the data of literature, attempts have been made to elicit the causes of the sudden appearance and spread of cholera in South America. The increase of cholera morbidity in Africa is associated with the activization of cholera in endemic foci and intensified migration caused by military conflicts in the countries of Central and East Africa. Cholera morbidity in Asia appears to be declining; however, large outbreaks of cholera, as well as diarrheal diseases clinically similar to cholera and caused by Vibrio cholerae non 01, serogroup 139, have been recorded. In Europe, including Russia, cholera outbreaks and sporadic cases, mainly imported, have been reported. The prognosis of cholera situation remain unfavorable due to the activization of epidemic processes and the constant risk of the infection being imported to any country of the world.

[The virulence of Vibrio cholerae isolated under different epidemiological situations]. / O virulentnosti Vibrio cholerae, vydelennykh v razlichnykh épidemiologicheskikh situatsiiakh.

The virulence of V. cholerae isolated on the territory of Russia and other CIS countries from environmental objects and from humans in different epidemic situations during the period of 1987-1991 was studied. The analysis of the data obtained in this study revealed that intensive epidemic complications were linked with the realization of the pathogenic properties of strains, characterized by the presence of the ctx gene and the absence of hemolytic activity. As a rule, in single cases or in isolated group cases of cholera V. cholerae hemolysin-negative strains without the cholera toxin gene were isolated.