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Problems of Particularly Dangerous Infections

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No 2 (2016)
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https://doi.org/10.21055/0370-1069-2016-2

REVIEWS

5-10 3993
Abstract
Epidemic outspread of Zika fever has given WHO authority to declare emergency situation in the sphere of international healthcare. Major risks for the Russian Federation are associated with the import of the disease by persons, infected in epidemiologically hazardous territory, or import of Zika virus vectors by transport means of international traffic. In this context, developed and normatively regimented is the complex of measures aimed at prevention of Zika virus disease, comprising activities to control import of the infection from enzootic territories, monitoring over the vectors of virus, Ae. aegypti and Ae. albopictus , and procedure for disinfection operations. Developed and introduced into practice is a home-made preparation for laboratory diagnostics and detection of Zika virus RNA using PCR. The article covers the issue of possible dissemination of the vectors in southern regions of Russia in view of climate warming. It is concluded that nowadays probability of local Zika virus transmission in “human-mosquito” cycle is extremely low and no complications of epidemiological situation on arboviral Ae. aegypti- and Ae. albopictus- borne infections are predicted.
11-13 774
Abstract
Given are the results of assessment of epidemiological and epizootiological situation on brucellosis in the Russian Federation in 2015. It is characterized as challenging. Compared to 2014 (368 cases, intensive index - 0.26), recorded is 5.1 % increase in the number of people infected with brucellosis (393 cases, intensive index - 0.27). The highest incidence rates among the population are registered in the North-Caucasian, Southern and Siberian Federal Districts, where the main source of infection is cattle and small ruminants. Revealed is a significant rise in brucellosis incidence in the Stavropol region too. External epidemiological risks, associated with the intensification of cooperation in the supply of livestock products from the Mediterranean countries, Middle East, and South America, which are endemic as regards cattle brucellosis, will remain pressing. Given the sustained adverse epidemiological and epizootic situation, taking into account the internal and external risks of infection with brucellosis, brucellosis incidence among the population is predicted to be within the range of 390-420 cases.
14-23 3636
Abstract
Cholera vibrios of nonO1/nonO139 serogroups (NAG vibrios) are well known as natural inhabitants of aquatic environments and as agents of acute intestinal infections (AII) with different degree of severity. On the background of the current vehement dissemination of the new highly virulent Vibrio cholerae El Tor strains, the moral and economic damage from NAG vibrios is not that evident, but still, not less real and rather significant. In spite of rare association with large outbreaks, NAG vibrios rank in the etiology of AII all over the world and pose a potential threat for the population health in our country. The paper reviews the present-day morbidity as regards NAG infections in various countries, including Russia; as well as the molecular premises of the agents’ pathogenicity and drug resistance. Analysis of the published data has revealed an utter heterogeneity of NAG populations, circulating in certain territories, by reference to the presence/absence of genetic determinants of pathogenicity, persistence, housekeeping and antibiotic resistance factors. Nevertheless, the joint gene-pool of the population includes rather a wide set of genes and can expand due to importations of strains, which differ from resident ones in the genotypes, from other regions. This brings about the danger of emergence of clones with higher pathogenic and, probably, even epidemic potential driven by gene exchange, and the consequences of their occurrence are unpredictable. Therefore, the NAG vibrios demand proper attention from investigators and sanitary-epidemiological institutions of the Russian Federation.
24-27 1106
Abstract
Outlined are the results of assessment of epidemiological and epizootiological situation on anthrax across the globe in 2015. Three human cases of cutaneous anthrax were registered in the Russian Federation. Detected were two epizootic foci with three cases of live-stock animal disease. 1-20 cases of anthrax in humans are forecasted in the Russian Federation in 2016. Adverse as regards anthrax situation is created in a number of near and far abroad counties. The highest morbidity rates among animals and humans are reported from Asian and African countries. Discussed are the results of investigation into the blunder of the US Department of Defense laboratory system, resulted in distribution of ineffectively decontaminated samples of anthrax agent to the US laboratories, as well as of other states within the past twenty years.
28-35 1475
Abstract
Overarching objective of vaccinology is a search of new adjuvants, directly influencing immune-competent cells and stimulating expressed adaptive immune responses. Adjuvants have been used for the enhancement of immune response for over a hundred years. A considerable number of recent adjuvants capable not only to reinforce antigen intake by antigen-presenting cells (APC) or deliver it to the sites of immune-competent cell localization, but also acting as immediate immune activators, are at various stages of trials. When selecting an adjuvant a special attention should be given to the efficacy of immunological memory activation, capacity for complex Th1 and Th2 stimulation, provision for expressed immune response in the context of vaccine dose tapering and lowering of the frequency of administration, and innocuousness for the organism. Nowadays preference is set on the modifiers of functions and signaling pathways of innate immunity receptors.

EPIDEMIOLOGY

36-39 784
Abstract
Objective of the study is to analyze epizootiological-epidemiological characteristics of the stationary hazardous as regards anthrax areas (SHA), situated in the territory of the North Caucasian Federal District (NCFD). Materials and methods. Official statistical data on morbidity rates in the Russian Federation and the records of the Rospotrebnadzor Administrations and Veterinary Administrations in the Stavropol Territory and the Republics of NCFD have been deployed for evaluation of anthrax incidence rates among humans and animals. Electronic cadastre for geo-encoding of SHA has been developed using software product ESRI (ArcGIS10.x) and topographical framework in the form of electronic maps M 1:200000. Results and conclusions. The studies conducted for the assessment of SHAs formation timelines and their activity during 1960-2014 have revealed that most of the SHAs fall under the category of the old-aged and non-manifesting ones. The highest peak of anthrax activity came in the period of 1960-1979. Further on, anthrax was registered within 1-3 years in scattered regions.
40-44 899
Abstract
Objective of the investigation was to differentiate the territory of the Republic of Bashkortostan according to the levels of risk of exposure to HFRS. Materials and methods. Utilized were the records on HFRS morbidity among the population of the Republic of Bashkortostan over the period of 1980-2014, collected in the Rospotrebnadzor Administration and the Center of Hygiene and Epidemiology in the Republic of Bashkortostan, as well as personalized data on HFRS incidence in the Republic over the period of 2009-2011. Key research method was GIS-technology based analysis. Results and discussion. It is established that 56.7 % of HFRS epidemic manifestations are in the forest-steppe zone, 24.3 % - in flood-plain biotopes, and 16.1 % - in forest area. Recorded is a high level of infection among the people aged 20-50. What is more, morbidity rates for men come up to 79 %, for women - 21 %. Children under 14 and individuals over 60 suffer much more rarely. Determined is the fact that HFRS-affected residential areas are situated 2.5 times closer to forest zones and 1.6 times - to flood plains, than those in which HFRS cases are not registered. Substantiated is the prospective of GIS application, first and foremost geo-coding, for epidemiological zoning of enzootic as regards HFRS territories, detection of areas where high risk of exposure exists, and performance of targeted preventive measures.
45-49 808
Abstract
The paper covers historical retrospective of mobile truck-mounted laboratory construction, used for diagnostics of infectious diseases in the Russian Federation, as well as information on analogous laboratories of foreign manufacture. From the standpoint of systemic approach and systemic-functional analysis, investigated has been experience of the Russian Research Anti-Plague Institute “ Microbe” in developing mobile complexes for indication and identification of infectious disease agents, I-IV pathogenicity groups. Outlined, scientifically substantiated and considered in depth are ten basic principles, underlying design and construction of mobile laboratories for laboratory diagnostics of infectious diseases.
50-52 684
Abstract
Objective of the study is to evaluate economic losses in the consequence of A(H7N9) virus emergence in the territory of the Russian Federation. Materials and methods. Economic damage from induced fatalities has been predicted using DALY index, taking into account the life loss, depending upon the age of the infected persons and associated amount of short-received gross domestic product (GDP). Results and conclusions. Since nowadays there are reported cases of the disease in China, one should expect individual cases of flu among those, arriving in the Russian Federation from this country. Economic loss is forecasted for the outbreak involving infection of two individuals with A(H7N9) virus; the age of the first patient is over 50, and the outcome of his disease will be lethal. Treatment expenses for two patients may come up to 10.9-21.8 thousand rubles, and economic impact from short-received GDP - up to 3900 thousand rubles.
53-58 938
Abstract
Objective of the study is to evaluate the current state of epizootic activity of natural zoonotic foci, as the basis for the development of prophylactic measures aimed at prevention of natural-focal infections during mass events. Materials and methods. Utilized have been reports from the Center of Hygiene and Epidemiology in the Republic of Tatarstan, the data provided by Rospotrebnadzor Administration in the Republic of Tatarstan over the period of 2009-2014, and literature references. Results and conclusions. The most pressing natural-focal infectious diseases are hemorrhagic fever with renal syndrome, tick-borne borreliosis, and tick-borne viral encephalitis. Yersinioses, leptospiroses, and West Nile fever are rarely registered. Tularemia infections have not been reported within the past 20 years. The period of 2009-2013 is characterized by the decrease in the numbers of carriers and vectors of the diseases, as well as epizootic activity of natural foci, which came up to minimum values in 2013. Emerged since 2014 increment in the abundance rates of the carriers and later the vectors can lead to the increase in the incidence of natural-focal diseases. In the territory of the Republic, allocated are the spatial combination areas of natural foci of the diseases of various etiology with high risk of population exposure. Previous to conduction of mass events it is necessary to enhance the epizootiological surveillance in the natural foci, the results of which lay premises for the development of complex prophylactic activities.
59-64 870
Abstract
Objective of the study is to differentiate enzootic, as regards tularemia, territories of the Moscow Region according to the degree of potential epidemic hazard, applying GIS-technologies. Materials and methods. Utilized have been archival records, held by the Center of Hygiene and Epidemiology in the Moscow Region and Plague Control Center, Moscow over the period of 1942-2014, literature and author’s data. Constructed have been two maps, displaying the peculiarities of tularemia dissemination in the territory of the Moscow Region, deploying GIS software kit - MapInfo Professional, 10.5. Results and discussion. GIS-analysis of the landscape confinement of the areas with sustained tularemia manifestations during 1942-2014 has revealed that regions of the longest persistence (10 years and more) are situated within the altitudes interval of 100-150 m A.S.L. in the territory of Upper-Volga and Meshcherskaya lowlands, Moskvoretsko-Okskaya valley, Zaokskoe erosional plateau, south-western part of Smolensk-Moscow highlands. Carried out is differentiation of enzootic as regards tularemia territories in the Moscow Region according to the degree of potential epidemic hazard. The results obtained will serve as the basis for the enhancement of the strategies for epizootiological monitoring over natural tularemia foci and for effective planning of prophylactic activities.

MICROBIOLOGY

65-68 796
Abstract
Objective of the study was to develop monoclonal immunoassay for the detection of the pseudotuberculosis agent, serogroup I. Materials and methods. Specific components, that were used for immune-chromatographic test-system development were mouse monoclonal antibodies of hybrid cell lines, obtained to lipopolysaccharide antigen of the outer membrane of the pathogen’s «cold» variant (YP-101N2V4, YP-105S5A10); and rabbit anti-species antibodies against murine immunoglobulins. Particles, (30±2) nm in the diameter, were used to prepare colloidal gold-antibody conjugate. Antibody concentration for conjugation was 10-15 % greater than the D580 exit point on the plateau. For the production of immune-chromatographic test-system a set of membranes - MDI Easypack - manufactured by «Advanced Microdevice», India was deployed. Finished conjugate was applied onto the membrane by means of impregnation. Antibodies in the selected quantities were applied onto the analytical and control membranes via Dispensers. Substrates coated with the conjugate and ready-made working membranes were vacuum dried in a heat cabinet. Assembled immune-chromatographic test-systems were cut off 4.5 mm each and tested for specificity and sensitivity. Results and conclusions. Developed has been immune-chromatographic test-system for the detection of pseudotuberculosis pathogen, serogroup I. Utilized have been monoclonal antibodies of the hybrid cell line YP-105C5A10 in colloidal gold conjugate and monoclonal antibodies of the hybrid cell line YP-101H2B4 in the test line. The test-system allows for the detection of Y. pseudotuberculosis strains, serogroup I, at concentrations varying from 500 ths. m.c.·cm-3 (8 of the 11 strains under study) up to 4 million m.c.·cm-3 and does not identify closely related yersinia and heterologous microorganisms in quantities of 100 million m.c.·cm-3.
69-74 939
Abstract
Objective of the study is to explore the feasibility of the long-term persistence of Yersinia pestis strains in association with ameba - Acanthamoeba sp. Materials and methods. Investigated has been interaction of ameba - Acanthamoeba sp., isolated from rodent burrows in the Pre-Caspian sandy, Volga-Ural steppe, and Pre-Caspian North-Western steppe natural foci, with 4 strains of Y. pestis of the main subspecies, 1 strain of caucasica and 1 strain of altai subspecies. Results and discussion. It is established that the strains of the main subspecies survive in the cells of ameba at 26 °C and 20 % humidity (modeling of the drought conditions in the natural plague foci) within 2-4 months of experiment, and 10-20 times longer that in pure culture. Two strains of the non-main ssp. have not demonstrated an increase in persistency in association with Acanthamoeba sp., which may occur due to degraded resistance to phagocytosis in the ameba of this specie. Using fluorescent and transmission electronic microscopy, it is determined that the cells of plague agent persist in ameba cells in individual vacuoles, enclosed in endoplasmic reticulum. The data obtained may testify to the possible involvement of ameba Acanthamoeba sp. . into sustainment of Y. pestis in soil biocoenoses of natural plague foci.
75-78 887
Abstract
Objective of the study is to conduct phylogenetic investigation of Yersinia pestis strains (medieval biovar) from plague foci of Russia and bordering countries, using SNP-analysis of the genome-wide sequences of these strains. Materials and methods. Carried out has been sequencing of 14 Y. pestis strains, medieval biovar, from 13 natural plague foci of Russia and neighboring states, as well as their comparison to 9 strains of the same biovar, contained in the NCBI GenBank database. Using software products - Wombac 2.0 and Bionumerics 7.1, revealed is the presence of 1875 core SNPs, on the basis of which a dendrogram of phylogenetic relations between medieval strains is constructed. Results and conclusions. In consequence of genome-wide SNP-analysis, it is established that Y. pestis strains, medieval biovar, from plague foci of Russia and bordering states are assigned to 2.MED1 phylogenetic line and fall under two major evolutionary branches, the first one of which includes strains from the Caucasus and Caspian-Sea regions, and the second one - from Central Asia and China. The data obtained can be used for the development of molecular-genetic methods for differentiation of Y. pestis strains, medieval biovar.
79-82 825
Abstract
Objective of the study was to elaborate the method for preliminary accelerated evaluation of antimicrobial preparation efficacy in case of in vivo brucellosis. Materials and methods. Outbred BALB/c mice with the acute septic experimental brucellosis, caused by intravenous inoculation with sub-lethal doses of the agent, served as biological models. Concurrently with the challenge, animals were given antimicrobial treatment. They took preparations of different types. Further, against the background of antimicrobial therapy, changes of quantitative microbe content in the internal organs of animals were studied, applying bacteriological method. Based on the data obtained index of antimicrobial activity was calculated, according to the value of which, it is possible to rank the drugs under study. Results and discussion. Results of preparation potency estimation, received with the help of the developed method, and results obtained after complete standard regimens show high-level correlation dependence (correlation ratio being 0.73), which makes the method suitable for screening of new antimicrobials in reference to brucellosis agent.
83-86 821
Abstract
Training of specialists in advanced methods of plague laboratory diagnostics and in the safety of works with its agent is associated with the necessity to select strains for educational purposes, allowing for the reduction of risk of laboratory infection at tutorials. Deployment of avirulent strains or those with attenuated virulence is the guiding principle in the case. Objective of the study is to detect basic virulence genes of chromosomal and plasmid localization in plague agent strains - candidates to be used for educational purposes. Materials and methods. Utilized have been 18 strains of Yersinia pestis . Investigations have been carried out with the help of reagent panel for identification of Y. pestis strains using real-time polymerase chain reaction (RT-PCR) with hybridization-fluorescent registration of results (“Gene Yersinia pestis Identification - HFR”). Results and discussion. In the course of the study, the strains, selected as the prospective ones, have been characterized by composition of the key virulence genes of chromosomal and plasmid localization. The operation has been performed by means of the reagent panel for identification of Y. pestis strains using RT-PCR with hybridization-fluorescent registration of results. Consequently to the assessment of molecular-genetic properties of plague agent strains, distinguished have been genetic variants (the genome of which lacks one or more key virulence determinants) which are the most relevant in the reduction of biological risks of training technologies at tutorials within the frames of the educational course “Microbiology and laboratory diagnostics of plague”.
87-90 1016
Abstract
Objective of the study is to evaluate the role of cadaverine in cholera vibrio adaptation to stress, induced by hypoxia. Materials and methods. Utilized have been 18 V. cholerae strains with different set of pathogenicity determinants. The strains are isolated from patients and from river-water. Results and conclusions. It is demonstrated that under experimental modeling of intestinal tract gas medium, cholera vibrios respond to unfavorable conditions of the environment by producing cadaverine. Its amount coincides with pathogenicity of cultures (it is higher in epidemically significant strains, than in the strains that lack genes of toxin and pilus production). It is established that the level of extracellular cadaverine production is greater than that of intracellular; but correlation of the parameters depends upon the oxygen and carbon dioxide concentration in the environment. Intracellular cadaverine is mainly generated at a high oxygen concentration (10-12 %); while under extreme hypoxia (<1 % O2) and in case of carbon dioxide level increase (9-13 %), its production markedly declines.
91-94 1084
Abstract
Objective of the study was to demonstrate practicability of data base creation, containing reference mass-spectra of agents of particularly dangerous infections, using MALDI-TOF mass-spectrometry, by the example of plague agent strains. Materials and methods. MALDI-TOF mass-spectrometry was deployed for the obtainment of mass-spectra of ribosomal proteins from the microorganisms under investigation with the help of mass-spectrometers - Microflex LT. Results and conclusions. Carried out was comparative analysis of the obtained mass-spectra of 10 Y. pestis strains and reference spectra of Y. tuberculosis , contained in commercial data base of MALDI Biotyper 3.1 (Bruker Daltonics, Germany). Developed data base was validated in the process of identification of plague microbe strains, isolated in the territory of natural plague foci of the Russian Federation. That data base provided for correct identification of Y. pestis strains up to a species.

BIOTECHNOLOGY, IMMUNOLOGY

95-101 812
Abstract
The review provides information on the major outcomes of research and development work, performed within the frames of the Federal Target Program “National system of chemical and biological safety” (2009-2014), aimed at elaboration and introduction of cultural techniques into the manufacturing of anti-rabies immunoglobulin. Described are the key phases in methodology engineering, deployed for the large-scale cultivation of fixed rabies virus, concentration of cultural liquid, quantitation of rabies virus using PCR, and immunization of producers. Obtained pilot batches of the enhanced anti-rabies immunoglobulin, complying with normative requirements to commercial formulations, testify to the effectiveness of the developed biotechnological and methodological procedures, as well as of the designed engineering-manufacturing project documentation.
102-106 770
Abstract
Objective of the study is to develop a reagent for the detection of lymphocytes with Yersinia pestis F1 antigen receptors. Materials and methods. Utilized have been: live plague vaccine based on the strain of Yersinia pestis EV NIIEG, formalin killed suspensions of microorganisms - Y. pestis , 3123, Y. enterocolitica O9 H-383 serovar, Y. pseudotuberculosis O1 2841 serovar; acetaldehyde-immobilized capsular antigen of Y. pestis F1 (obtained applying Baker methodology), lipopolysaccharide of Y. pestis K1, and bovine erythrocytes. Bovine erythrocyte F1 sensibilization has been performed using rivanol. Lymphocytes from blood have been isolated in density gradient ficoll-verografin 1.077. Lymphocytes with Yersinia pestis F1 antigen receptors have been detected by means of reagent adhesion onto the isolated lymphocytes. F1-free erythrocytes serve as controls. After the exposition, 7 evaluations of specificity to F1 and the lymphocytes, binding control reagent, have been carried out. Deployed have been 8 rabbits, immunized with live vaccine EV, and 2 rabbits, immunized with inactivated vaccine EV. Examined have been EV-vaccinated 5 persons. Results and conclusions. Identified is optimum sensibilizing dose of F1 antigen (250 µg/ml). Specificity of lymphocytes with receptors to F1 is demonstrated in inhibition experiments applying homologous and heterogeneous antigens. Lymphocytes with receptors to F1 (LRs) have been detected in peripheral blood of all rabbits and humans, immunized with vaccine EV. LRs have been registered since day 2 till day 35 in the rabbits, and in humans - since day 2 till day 14 after vaccination. It is shown that in case of revaccination of humans, LRs emerge and disappear earlier, than in case of primary immunization.
107-110 1022
Abstract
Considered are the problems of handling of the vaccine strains Yersinia pestis EV NIIEG, Bacillus anthracis STI-1, Francisella tularensis 15 NIIEG, and Brucella abortus 19 BA, utilized for manufacturing of live vaccines against particularly dangerous infections, in connection with absence of normative legal document, specifying the algorithm for storage and handling of strains after production stage throughout the shelf-life (10 years). It is indicated that under current conditions the system of handling and record keeping on the transfer of strains of vaccines against particularly dangerous infections is compromised. It has led to disruption of interdepartmental cooperation in the transfer, testing, maintenance, and storage of the latest manufactured batches.


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ISSN 0370-1069 (Print)
ISSN 2658-719X (Online)